101 questions about doing my own conversion...

[truckguy]

Hi People. I'v been lurking here for a few days, trying to piece everything together in my mind for converting a HDT into a motorhome for RV travelling. I've got a ton of questions...

A bit myself first... we presently have a 32' 5er we pull with a 2000 Ford F250SD diesel. We just returned from a 3000 mile trip to Sacramento. The combo works pretty well, but we found the truck to ride quite rough on the California roads. Fuel stops were a headache too. The tank on the Ford is small. Power was adequate but not plentiful. Fuel economy was 11 MPG or so. A bathroom and room for the kids to move a bit while travelling would be great.

The 5er is a nice size and we are pretty comfortable in it, but I find they need a lot of maintenance. They aren't designed the best. Everything is sort of too light and hard to work on.

I am very mechanically inclined. I've built a lot of stuff in the past. I am a good welder, but body work is not my forte. I'm good at wiring and plumbing. Woodwork is not my thing either.

I've driven medium duty tandem trucks with 10 and 13 speed transmissions, but only for a few days and that was 10 years ago. I have my air brake ticket, but I'm rusty. I've never ridden or driven a class 8 truck and the medium duty trucks I was driving (International and Mack) weren't in the best shape.

I've looked at motor homes and they look like high maintenance to me as well. Like a 5er with a drivetrain. They don't seem to be very big inside either and only the expensive ones have an 11 or 12 litre engine. Most of the floor plans are for retirees, not families. And I don't like the auto transmissions either. Kills MPG and something more to break.

I've looked at bus conversions, but the shells are really expensive for what you get and they look to require as much work as converting a HDT, maybe more. Most of them use 2 stroke GM engines, so an engine swap is almost a must, the roof will need raising, there will be rust to fix in the front and rear subframes, etc. (Lots of bus specific stuff looks harder to work on.) I hate the automatic transmissions in buses. A HDT appears to be lighter than a converted bus too.

One thing I hate about both buses and motorhomes is not having anything between you and the front of the vehicle if you are ever in an accident. The driver's compartment on most motorhomes is set back 3-4 feet from the windshield, but there isn't anything substantial in front of the driver. Just fiberglass and air. I've never been in an accident, but I'd rather be in my pickup with sheetmetal, a frame and a diesel engine in front of me and an airbag in the steering wheel than be at the wheel of a motorhome.

I don't need a completed conversion for a few years, but I'd like to start piecing things together and planning. Our RV situation has been bothering me a bit lately and I'd like to get a direction finalized and start moving towards it. As it is I am going to spend some money and time updating our truck and trailer, but if I can see getting a HDT conversion going in the next year or so, I'll go light on the pickup and trailer upgrades.

I quite like what spooner has planned for his Pete. I'd like to curve the sidewalls on my conversion like he is doing on his.

So... on with the questions...

1) Ride quality and noise. Can a heavy duty truck (single rear axle, KW, Pete or Volvo) with a large "box" on the back be made to ride nicely on rough interstate roads ? As good or better than a Ford Superduty ? (Which isn't saying much...) How noisy are these trucks under load ? Can these trucks be made to ride as nice and be as quiet as a bus conversion ? (MCI 102,say) Is anyone converting the front axle to air ride ?

2) Fuel economy. Can one get 11-12 MPG out of a HDT conversion running 60-65 with a light foot ? Assume we keep the roof line as low as possible and streamline everything we can and keep the weight down. 13 speed, double OD ? 3.08:1 rear end ratio ? Or taller ? 2.73 ?

3) This question might cause an argument... what is the best conversion candidate ? KW T2000 ? Pete 379 ? Volvo 770 ? Something else ? I want something really aerodynamic with a good ride and quiet.

5) Height ? How high are the frame rails on these trucks and how high does the floor need to be above that ? And then how high does the roof need to be above that ? And how much does the overall height have to do with aerodynamics and fuel economy ? Is anyone lowering the chassis on these trucks or running smaller tires ?

6) Length/Turning Radius/Single or Tandem ? What is the "Back of Cab" measurement on the various HDT ? I guess by BOC, I mean to behind the drivers seat as everything from there back will be motorhome as far as I can tell. (I am thinking of doing something like spooner is.) If I run a 36 foot box with say 2 slideouts and stay weight conscious, can I get away with a single rear axle ? What sort of wheelbase and turning radius will it have ? Can anyone comment on parking in tight quarters, ie not drive through stalls ?

7) Basement Rustproofing ? When I look at the MCI busses, the entire basement and frame for that matter is made from Stainless steel or aluminum. And even then there can be corrosion problems. If one looks at the basement and frame of an Eagle, one typically finds RUST, to no end. So... how does one build the basement on a HDT conversion so it doesn't rust ? The only thing I can think of is to frame the lower stuff out with aluminum and use fiberglass expoxy panels ? I can't see using steel for it or am I being too picky ?

8) Box details ? Is anyone making their box 102" wide ? Some busses and some "toy hauler" trailers are now 102" wide. What sort of steel is being used in the walls ? (1.5" square tube x 1/8" wall ?) Is anyone worried about the integrety of the box in case the truck is laid over or rolled ?

9) Frame stretching ? I've helped stretch the frame on a couple MDTs, but I didn't pay much attention at the time. If I remember correctly, we cut the frame at an angle, spliced in another piece of frame and then plated the inside and outside, welding the channels. Is this how it is done on a HDT ? I doubt it as I don't think the rails can be welded. So how is it done ? Is a second carrier bearing added for the driveshaft ?

10) Levelling ? Does a HDT need a hydraulic jack kit like a motor home does or can they be leveled with the air bags like some of the buses conversions are ? (By adding special valves and maybe converting the front axle to air ride ?)

11) Exhaust System ? It appears to me that most of the aerodynamic HDTs have the exhaust stack exiting behind the cab, right where my box would be. What does one do to fix this ? Put a muffler under the truck with an exhaust exit out the side ?


What else am I missing ?


Thanks.

[Warpath]

I will give you my opinion on the items I can relate to.

#1: No! (I won't sugar coat this, just being honest) A class 8 truck usually runs 12,000 plus front axle and 20,000 rears. Unloaded it is going to shake the hood and the dash and anything else in the truck when you hit rough roads. This is why they run air chairs and air cabs to at least keep the driver as comfy as possible. Run the truck fully loaded like it is meant to and it will ride like a caddy. When I bought my FLD 4 years ago and bobtailed it around I was very disappointed in the ride. I was really worried that is was going to ride that bad once I had my conversion on and I was bummed. I did add Broc's air ride system to the front axle and that did help, but the truck still rode rough. Once I put my conversion on which added 18,000 plus pounds to the chassis it rode great. In your application with the small trailer it is going to ride like a class 8, and I would not assume it will ride like a dually, I have had both. (Not sure from the info you provided above if you are thinking about pulling a fifth wheel RV or put a motorhome conversion)

As far as noise. You have to love the sound of a real diesel motor and the whistle of the turbo. If you do your gonna love a class 8! They are noisy, newer trucks are much better, but if your sitting on 11 plus liters of iron it rumbles like a freight train under throttle and you always have the whistle of the turbo. If you love that and your wife doesn't well, you maybe want to reconsider, although you may not hear her complaining.

I really recommend that you get into a Class 8 with the wife and take a spin, and for the most part they will all ride about the same. They all sit on pretty much the same chassis, big difference being front axle rating.

Truck makes will get as heated a debate as the pickups get. Some swear by KW or Pete, but I have talked with alot of truckers and most of them like the FL ride & ergo of the cab (newer versions), they just don't look as cool. And sometimes it better to look good than feel good.

#2: Yes & No My Cummins M11 & Fuller 10 speed got me 11 mpg with my conversion (weight was approx 33,000 with car jeep in tow) So yes with a pre-emissions motor, but with the newer emission motors I don't know if that is still possible.

#3: Duke it out!

#4 or 5: The big issue with lowering is that your gonna need room for the overhang past the back axles. If you have a 10' overhang you will be o.k. with current chassis height in 95% of all situations. The longer you go the worse you will drag. The lower the trucks ride height and you will need to shorten this overhang.

#6: With 36' box you will need tandems. Depending on truck and cab config most anything over 30' will require tandems do to wheel base issues. Keep your wheel base under 300" if at all possible and you can get around pretty well. My last conversion was 336" and it was completely miserable to maneuver. I am not saying it can't be done, but I am telling you from personnel experience DON'T DO IT! My current conversion is 295" and it is like night and day.

#7: If you like running in the winter, than aluminum might be your best bet. Most conversion companies use a steel frame rust proofed with galvanized boxes. Hit salt once or twice and the rust will start even if your good about flushing the chassis after salty travel. I am constantly painting and cleaning the chassis to keep this under control.

#8: Most run 96", not sure if Kingsley is 102 or not. If it gets laid over its done anyway, you just want it so if it does happen you can walk away.

#9: The good ones cut the frame at the center point of the current chassis from back of cab to end of rails, add in the stretch, butt weld, and than add a solid new c channel over the stretched rails from cab back which is bolted in place. Don't go cheap here, I have seen a few bent chassis when this is not done right.

#10: Your gonna want levelers, air bags are not going to be enough unless you hang out at the top resorts with super level parking spaces.

#11: Under box out the side, definitely want mufflers! Loud pipes don't save lives when they resonate under the conversion box. You could run some shorty stacks behind the cab if you like black sooty exhaust streaks down the side of your conversion box. I have seen one where they had fackey stacks and the real exhaust out the bottom. to much trouble for me.

Great questions!

Bill

[Dave B]

NRC Modifications does 101 inches wide in answer to your number 8 question.

[John (C-IL)]

Truckguy, don't know if you have been over to racing junk.com but it is an education just looking at the ads.

IMO I think I could buy a rig cheaper than build my own. It's kinda like houses, whatever you think it will cost.....double it.

Racing Junk

Go to the towing section and "toterhomes"

[truckguy]

Thanks for the replies.

Truthfully, I won't be very interested in doing a conversion if the ride and noise level isn't as good or better than my SD. I am pretty sure I could build a bus conversion that would ride as nice and be pretty quiet, at least up at the front.

I keep coming back to 5ers pulled by HD diesel pickups. It isn't an optimal solution but it seems to have the least amount of drawbacks compared to others.

The Toterhomes on racingjunk.com are interesting. I think it is a mistake to build them on a MDT. Not enough power. The ones I am interested in are listed for $150K+ and I think, rightly or wrongly, that I could build a pretty good conversion for that sort of money.

For the record, I am not looking to tow anything with my RV.

Someone tell me I can build a really nice riding HDT conversion !

[truckguy]

I've been doing some reading on this site and others. An MCI 9 and other buses use what are called "air beams", at least on the front suspension. The air bags have open bottoms and are attached to a hollow but enclosed beam, dramatically increasing the air volume and thus softening the ride.

Could the same thing be achieved with a "ping tank" ? Has anyone done this ?

[Marc]

Well Sir, If I understand this correctly, You have and enjoy a 5er.?? But you are not real happy with the Ford P'up as a tow vheicle. I hope I got that right. If I did what are the complete specs on the truck?? I have had Ford P'ups all my life I do not feel that a F-350,450 or the 550 with a 7.3 or 6.0 Diesel Engine are "REAL TRUCKS" to use to pull a
loadded 5er around. Even if you have modified it with a chip,exhaust and more air it is still not a real truck, As in Stopping It, Frame, Tires and the complete front end. What is your 5er Gross Weight Loaded Ready to go Not Hooked To The
Truck?? I THINK the F-550 only has a GVW of 19,000 pounds maximum. Hell the truck weighs 10,000-12,000 lbs. Have you even
figeured fuel mileage??? Air Ride Today can be mounted on any type of vehicle there are a lot of mfgs.out there. I am gonna take a guess that your 5er loaded weighs 13,000-15,000 lbs. with everything needed for a two week trip. Even using
the light side adding 10,000 & 13,000 lbs. is a total weight of 23,000 lbs. You are maxxed out by 4000lbs. before you leave
the driveway. At a minimum I would use a 30,000 GVW Real Truck on 22.5 rubber with air brakes 300+ H.P. and an engine brake.. One could be built w/a 8'-10'box w/nice seating and all the comforts of Home. The Bottom Line Here Is Safety To Protect Your Family And 5er. JUST WENT BACK AND SAW THAT IT IS A F-250 SOMEONE HAS SURE BEEN WATCHING OVER YOU,
DO YOU HAVE TO PUSH YOUR GONADS AROUND IN A WHEELBARROW?????? AND I THOUGHT I CROSSED THE EDGE OF THE ENVELOPE!!!!!!!!!!!
Regards,Marc

[truckguy]

"Well Sir, If I understand this correctly, You have and enjoy a 5er.?? But you are not real happy with the Ford P'up as a tow vheicle. I hope I got that right."

You do.

"If I did what are the complete specs on the truck??"

F250SD running 300HP with an exhaust brake. Manual 6 speed transmission. Crew cab.

"I have had Ford P'ups all my life I do not feel that a F-350,450 or the 550 with a 7.3 or 6.0 Diesel Engine are "REAL TRUCKS" to use to pull a loadded 5er around."

They are certainly adequate. I've read the bashing that various people have done on pulling 5ers with HD pickups versus MDTs and I don't agree. Certainly a MDT has better brakes and is more stable, but the Ford HD pickups are more than up to the task. Our trailer is 9500 pounds loaded up and the truck handles it very well. We can climb any reasonable grade (6%) at 50 MPH and braking isn't a problem either with the manual transmission and exhaust brake. On anything less than about 7% the engine braking alone will easily control the speed. Wheel brakes are only used for emergency stopping.

The things I don't like about the F250 are the ride and the lack of fuel capacity, both of which could be rectified.

People brag about the HP of buses and motorhomes. However, those units usually weigh a lot more too. I've got 600 ftlbs and 300 HP on 16,500lbs. A typical 33,000 pound RV would need 600 HP to have the same performance as I have. In fact, one of my criticisms of MDTs is that they don't have any more power and yet they weigh a lot more than a HD pickup. They do have a wider torque band though. But I absolutely hate automatic transmissions, which a lot of people get in their MDT. (I love autoshift transmissions though.)

"Even if you have modified it with a chip,exhaust and more air it is still not a real truck, As in Stopping It, Frame, Tires and the complete front end."

As far as stopping goes, if the brakes on the trailer are good the unit stops surprisingly well. A lot of MDT owners feel they need a MDT to stop the trailer. Well, in the real trucking world, trailers have enough brakes to stop their own axle weight. The tractor has enough brakes to stop its GVW too. And our setup does this well. What most of these MDT owners really needed was better brakes (or properly serviced brakes) on their 5er.

Tires ? I haven't had any tire trouble with my truck. The rears will wear quickly if you pull aggressively in the mountains. I got 50,000 miles on the first set and the second set is still running. Load range E tires are rated at 3420 each IIRC. The front and rear axles on our truck weigh 4400 pounds each when hitched or 2200 pounds per tire.

The frame is fine. We've been pulling this trailer for 7 years with no problems. It is very stable, even in cross winds. The key there is a dual pivoting hitch. Single pivoting hitches will flex the frame of the truck and affect the steering.

"What is your 5er Gross Weight Loaded Ready to go Not Hooked To The
Truck??" 9200 to 9500 pounds, depending how we have it loaded. And yes, I have weighed it. The GCWR on my truck is 20,000 pounds. My truck weighs 6600 pounds empty and 7000 with us in it. Total rolling weight is 16,500 typically.

"I THINK the F-550 only has a GVW of 19,000 pounds maximum. Hell the truck weighs 10,000-12,000 lbs."

The heaviest pin weights I know of on regular 5ers are 3,000 pounds. The F550 has GCWRs of 26,000 to 29,000 pounds. They can weigh as little as 9,000 pounds, leaving room to pull up to a 20,000 pound trailer. They run 19.5 rubber and have heavy rear axles and big brakes, so that isn't a totally outlandish thing to do. What they don't have is the right engine.

"Have you even figeured fuel mileage???"

I'm at 9.5 to 11.5 depending on conditions. It isn't terrible. I pull with 3.73s and that holds OD on grades up to 2% or so. I probably average 11. Head winds really kill it. F450s and F550s usually have 4.30 and 4.88 axle ratios. The engine is screaming at 65MPH. The fuel economy is terrible.

"Air Ride Today can be mounted on any type of vehicle there are a lot of mfgs.out there. I am gonna take a guess that your 5er loaded weighs 13,000-15,000 lbs. with everything needed for a two week trip. Even using
the light side adding 10,000 & 13,000 lbs. is a total weight of 23,000 lbs. You are maxxed out by 4000lbs. before you leave
the driveway. At a minimum I would use a 30,000 GVW Real Truck on 22.5 rubber with air brakes 300+ H.P. and an engine brake."

Your numbers are wrong. I gave you my real numbers above. And in the scenario you gave above (13,000 pound trailer), an F550 would work pretty well if it had better engine/gearing in it. The GCWR of an F550 can be 29K.

"One could be built w/a 8'-10'box w/nice seating and all the comforts of Home. The Bottom Line Here Is Safety To Protect Your Family And 5er. JUST WENT BACK AND SAW THAT IT IS A F-250 Eek SOMEONE HAS SURE BEEN WATCHING OVER YOU,
DO YOU HAVE TO PUSH YOUR GONADS AROUND IN A WHEELBARROW?????? AND I THOUGHT I CROSSED THE EDGE OF THE ENVELOPE!!!!!!!!!!!"

These trucks handle 5ers real well. We drive 600+ miles a day in all types of conditions, except snow. We are not overloaded. My friend pulls an 11,000 pound trailer without any problems. The 99+ trucks were a big step forward from the previous trucks. Better brakes, 6 speed versus 5 speed, better mirrors. The exhaust brake and manual transmission make a tremendous difference on the down grades.

I've driven empty tandem trucks with 250HP weighing 15,000 pounds and my F250 compares well as far as acceleration goes.

Here is a shocking stat for you. My truck has pulled the 5er for 7 years, about 2500 miles a year in mountainous conditions and now has just about 100K on it. It is still on the original brake pads. I'd say the front pads have 40% left. I'll probably change them this summer.

What I don't like about this setup is:

a) driving a large truck around as our daily driver, although it works
b) the ride is rough on rough roads
c) the engine and wind noise is pretty high
d) wife and kids can't sleep or eat or go to the bathroom while we are travelling like they could in a motorhome or bus or truck conversion.
e) lack of fuel capacity. 25 gallons on my short box. Fuel stop every 300 miles. Huge hassle getting into small stations with a 5er in tow. Truck stops are fine.
f) 5ers aren't built really well. Lots of little marginal craftsmanship/design issues. And they can be surprisingly difficult to work on.

Mainly what I want is more all round comfort when travelling.

I'll shock you once more. Sometimes I pull a small boat behind our 5er. That is right, I tow doubles. It would weigh 1200 pounds with the trailer. I don't do it in the mountains though.

[Warpath]

truckguy -

I guess you have to choose which benefits are more important to you.

From what it sounds noise and ride are at the top. And with a HDT your gonna have noise and a rough ride at times. You can add airride and ping tanks to try and smooth it out, but the more you soften the ride the less stability you'll have in cross winds, cornering and when trucks pass you.

If you like the sound of your current diesel, than you'll love the sound of a 300 + hp Cummins, Cat, Detroit, Mercedes will pump out. But it's anything but quiet. For me I love it, nothing better than 12 hours at the wheel and at the end of the day all you hear is a turbo whistle ringing in your hears. It doesn't bother my wife at all and many times it puts her to sleep. (she not driving) So it works for us.

So 2 drawbacks to a HDT, and actually 1 once you throw some weight on it's back. But what you gain far out ways those 2 drawbacks; stopping power, reliability, 24/7 service, pulling power, safer in an accident, and stability in most any wind condition. And I am sure I'm missing some others.

Is a bus going to ride better than a truck conversion, most likely and for sure quieter since the motor is 40' behind you. But a HDT is much cooler than a bus any day!

Some great sites to check out to further your knowledge of HDT as a tow vehicles would be escapees.com they have HDT forum that is real active. And busnuts.com for bus conversion info.

Class 8 trucks are definitely not for everyone, kinda has to be in your blood. Two years ago I drove back to Cleveland from San Antonio (1450 miles) left at 8 a.m. Saturday mourning and was pulling in the driveway Sunday at around 4 p.m. Ran mainly at about 65 mph and even stopped at a Hampton Inn for a good nights sleep at 9 p.m. I did all of the driving and when we got I home I was not dead to the world, actually washed the rig before putting it away. Sitting in my comfy air chair floating along, never sawing at the wheel even when we hit the Okie winds. With 300 gallons of fuel on board, never had to stop for fuel, and with the air chair keeping the body form jarring only stop twice a day to hit the restroom. You just can't do that in a F250 pulling a trailer with out killing yourself.

As I mentioned before, definitely take one for a spin you may just fine that you have big truck blood running through those veins

Keep us posted

[truckguy]

I guess you have to choose which benefits are more important to you.

From what it sounds noise and ride are at the top. And with a HDT your gonna have noise and a rough ride at times. You can add airride and ping tanks to try and smooth it out, but the more you soften the ride the less stability you'll have in cross winds, cornering and when trucks pass you.

There should be some happy medium here. People seem to tell me that HDTs ride pretty well loaded with the stock spring rate. With a smaller load, reducing the spring rate should provide a similarly good ride with similar handling.

Is a bus going to ride better than a truck conversion, most likely and for sure quieter since the motor is 40' behind you. But a HDT is much cooler than a bus any day! Big Grin

I don't understand why a HDT conversion couldn't be made to ride the same as a bus. Can anyone give me a reason ?

Class 8 trucks are definitely not for everyone, kinda has to be in your blood. Two years ago I drove back to Cleveland from San Antonio (1450 miles) left at 8 a.m. Saturday mourning and was pulling in the driveway Sunday at around 4 p.m. Ran mainly at about 65 mph and even stopped at a Hampton Inn for a good nights sleep at 9 p.m. I did all of the driving and when we got I home I was not dead to the world, actually washed the rig before putting it away. Sitting in my comfy air chair floating along, never sawing at the wheel even when we hit the Okie winds. With 300 gallons of fuel on board, never had to stop for fuel, and with the air chair keeping the body form jarring only stop twice a day to hit the restroom. You just can't do that in a F250 pulling a trailer with out killing yourself.

On our last trip we pulled 1300 miles from Friday morning at 8AM to Sunday at noon. It doesn't kill one to do that in an F250, but one is a bit tired.

I'm not a diesel junkie. I could do without listening to a turbo whistle while I drive. If they all performed the same, I could like a HDT, bus or motorhome equally well, save I have real problems with the driver safety with the later two.

But what you describe, ie travelling long distances easily in relative comfort, is my primary goal.

"As I mentioned before, definitely take one for a spin you may just fine that you have big truck blood running through those veins Wink"

I'm wondering if using a HDT with a nice big sleeper as my TV would be ideal. The problem with that is the lack of a smaller daily driving vehicle.

I'm a bit turned off of a HDT conversion by the length and lack of maneuverability in smaller campsites. You would probably be amazed at the diverse and difficult locations we can get our 5er into with the F250. After 7 years of RVing with it, one gets pretty good at backing a trailer into tight sites.

This discussion has been very helpful, even if I haven't arrived at a conclusion yet.

[Marc]

Well I am totally confused now. "Please Do Not Take This The Wrong Way" I am not real smart but I am big and can lift heavy things.I cannont even understand what it is your asking now,It seems to me that you already have your
answers.You certinly have done your homework Sir. I think that there is a guy that would be a great asset to you and between the two of you you will get it all fiqured out. He goes by the name of KayeRivercity I belive over on the Escapee
Site I think. Good Luck to to you.

Regards, Marc

[Gary Atsma]

A few notes on "Class 8 Truck Ride"-
About 3 weeks ago I rode along with a co-worker from Astoria, Oregon to Central Calif. in a T600 Kenworth with a new 20' forage box for a truck bed. This truck had air ride rear susp., NON-air ride cab, and the driver got an air-seat. The passenger (me) got a non-suspended seat that DOES have good cushions. At the start of the trip I figured I was in for a rough ride, but was VERY pleasantly surprised, in that the ride, while firm, was in NO way uncomfortable! We cruised at speeds from 55 to 65, depending on conditions, usually drizzly rain ( hey, this is Oregon we're talking about here!) and good traffic conditions. After approx 14 hrs. we got home, and I was not the least bit sore! TIRED, YES! But not sore. The forage box on this truck weighed a lot less than a typical conversion would have, plus it was a tandem axle, plus a shorter wheelbase than any conversion would have. Not an ideal ride setup, but I guess the bottom line here is that one does not necessarily need air-everything to get a good ride
Oh well, enough of all this. I'm off the soapbox......
Gary

[truckguy]

The story about the ride was a good one.

I started out asking questions about doing a HDT conversion, but the topic changed because I was told the ride wouldn't be what I wanted. From there I got into educating why I use an F250 to pull our 5er.

The crux of my question has become how do I build something better than my current setup. (F250 and 5er.) The main limitations of my current setup are in the area of travelling, that being rough ride, limited fuel capacity and the 5er being on the high maintenance side of things sometimes. Access to the living area while travelling (bathroom, kitchen, etc.) would be great too.

I think the answer is to build a shorter HDT conversion so that it is maneuverable (single axle) and spend some time soundproofing it and possibly tuning the suspension.

A bus is out of consideration because of the safety factor for the driver in a crash. Ditto for a motorhome.

A HDT pulling a 5er is out of the question because I don't consider an HDT a suitable daily driver while we are parked. Although I know other people do it.

Tell me how to make a HDT conversion ride really well ! And then lets go back and discuss the questions I posed earlier.

We should be able to make a HDT conversion ride as nice as a bus, right ?

[Gary Atsma]

I think the way to go would be to find a truck with air ride rear suspension (no-brainer, at least 80% come that way), put in air-suspended seats for driver AND passenger, then put a Brock's Ad-a-Ride front air suspension kit (ask Warpath about this one). I would say that between all this air ride stuff, the ride would be QUITE tolerable. I personally believe buses have a rather queasy ride, to the point of actually being mushy. I would not want my truck riding like a bus. As you may surmise, the Oregon trip sort of opened my eyes on a few things.
Also, I agree on doing a shorter HDT conversion, maybe 18-20' coach length, behind a cab with integral 30-40" sleeper to get the extended-cab effect. This is what I have in mind to do when I get to putting my rig together. Are we on the same page here?
Gary

[truckguy]

I was thinking more like 30 feet from behind the driver's seat, which probably makes the "box" 24'. (72" sleeper ?)

Our 5er is 32 feet with one slide, but you lose a bit of volume/space in the bedroom.

I want to run a single rear axle. Our 5er weighs 8500 empty. If you stripped off the axles and pinbox, it would weigh 8000 ish. How heavy are the steel boxes ? It would be great to keep the conversion under 20,000 pounds. Not to sound redneck, but has anyone bought a travel trailer and put it on the back of a truck ? I bet it could be tied in quite nicely, although it would have more frame than it needed and a few other details would be... odd.

How light can a single axle HDT be ? I thought Western Star was advertising tandems at 14,000 pounds.

Now how does one build a rustproof basement ? I don't want to build this thing and then have to rebuild it a few years later.

Aluminum would be pretty expensive, right ? I want storage volume like I'd have on a bus.

Anyone care to comment on the frame stretching question ? (BTW: saw pictures of a Bigfoot leveling system being installed on an M2 (IIRC) and they WELDED them on. What is up with that ?

I like the look of the M2 and I bet it is lighter and has a shorter BOC dimension. I'd love to throw a C12 or ISL in one. I wonder if they could be made to fit. I'm turned off by only having 330 HP available in the M2.

[Gary Atsma]

The M2 can be had with the engines you mention (I THINK), but only in the 112 version, not the 106. Also, tandem axles normally have about 40,000# capacity, and singles up to 23,000#.

[Wick]

Truckguy,
We have had the same setup as you and come around to the HDT conversion for the practical reasons that have been stated here. I feel like I have alot of experience on this subject so here goes......
You will never make an HTD conversion ride as good or as quiet as a bus conversion. You can make it ride very comfortable and quiet enough for most. Check out the pictures of my unit on this site. You will see that we kept the sleeper and added a 30ft box. It serves us quite well. It does not turn as well as my first one or as well as the one Warpath built, but I am very comfortable in driving it as is my wife and we understand the turning limitations.
Check out how I re-did my exhaust. Exhaust If you build a conversion and lower it then you may want to run yours the same way.
We pull a 32ft tri-axle trailer with 27,000+ lbs so mileage is not over 10mpg at the 75+mph I usually drive. I have a 470hp Series 60 12L engine with an autoshift. It does a very good job for me even though I do not think this autoshift shifts as well as my last one.
I think the difference in comfort for the family with an HTD conversion over the f250 with the 5er will be great.
If you do a conversion then you can always tow a vehicle behind you to use once you get where you are going.
You still have a ton of hands on research to do before you make a descion....
Good Luck
Wick

[Marc]

Very well put Wick!!! And as a Gentleman to Boot. "TOUCHE"

Regard's
REAL DUMB,FATTER AND A LOT HAPPIER NOW!!!
aka/Marc

[kblackav8or]

If you want a really unique hybrid find a converted Crown Supercoach - early 70's 40 footer or the ultra rare 35 with a 855 Cummins and a 10 speed roadranger. They run a Mack air suspension most times and have the normal truck fore/aft engine axle arrangement. They are considered kind of tough to convert due to the shape but they are really overbuilt compared to any highway or other school bus. I have seen some really cool ones but they are hard to find. Often referred to as Bruck's. I almost bought one and posted the pictures in the picture section. They aren't for everyone either but are equally unique compared to what you buy at the RV dealership and is out of the box.