Transmission Questions. Auto vs Manual. What determines which type is ordered?

[BravestDog]

Sorry to bother all of you again, but more questions as usual.

I just found this Volvo 770 on ebay with a 10 speed auto shift transmission. Most trucks I see have manual transmissions.

1. My question is, what determines what type of transmission a truck gets when it is ordered or used? Auto or manual?

2. Is there a variety of automatics and manual transmissions available or is there just a few choices?

3. What determines whether a truck gets an automatic or a manual transmission and what type they get? Are there some applications where a auto is better than a manual and vice versa?

4. What is the price and life span difference between the two?

5. If you wanted a truck with an automatic for a conversion, so anyone could drive it, should a person purchase a truck with an automatic from the beginning or can you switch transmissions later..., or would that be a foolish, expensive error, to purchase a truck with a manual and then switch to an auto?

Generalizations and estimates are fine. Just trying to get a big picture idea.

I could understand if a truck is carrying maximum loads up and down mountain roads, that a many speed transmission would be a good idea to keep the motor in its proper power range...

Thankyou.

[Warpath]

Companies are installing auto's to increase the pool of drivers they can pull from, increase the life of the equipment and save fuel. The thinking is that a auto is in the right gear at all times and a driver can't screw up.

Not sure many truckers would agree with all of that. Drivers of auto's are just throttle jockeys in the eye's of most truckers

If you have any idea whats so ever that you would possibly want to sell your conversion in the future, don't even think about using a manual. You will loose resale value big time! Go to racing junk and look at the price the manuals are fetching.

Now having had a manual and a full automatic, I can say that the manual was much more fun to drive. With a manual, time in the seat seemed to pass much quicker. I think that is because you need to really be aware of what is going on around you at all times. The auto is awesome in traffic & back roads where shifting manually tends to get tedious.

Getting back into the selling game again, I have to wonder why you would want to build your own. The pool of used rigs is growing like crazy and the prices are insanely low.

I truly think the conversion market is in trouble. Even though conversions are built incredibly well and should last for a very long time; dealers, manufacturers and selling owners have driven all of the resale value out of the used market. There is no way that customers can continue to take huge hits in value and that will drive customers out of the market.

For now it is a buyers market and now is the time to take advantage of the great values to be had.

[BravestDog]

Even though conversions are built incredibly well and should last for a very long time; dealers, manufacturers and selling owners have driven all of the resale value out of the used market. There is no way that customers can continue to take huge hits in value and that will drive customers out of the market.

Warpath,

I'm trying to read between the lines here so pardon my summary if it's incorrect.

Are you saying that conversions cost too much initially, (the manufacturer must make a profit along with the dealer, and all the others who assist with building it) and then when it comes time for the owner to sell their used conversion, the converison sells for a lot less than what they paid causing the owner to take a huge loss?

Is this sort of what you are saying?

Back to the transmission questions, are there only two types of auto's or are there more than two types?

1. one type is fully auto like a small car. put it in gear ie "D", step on the gas and it shifts up and down according to the computer program, rpm, load...? but you can manually shift it gear by gear or keep it in a specific gear if you want?

2. other type, you use a clutch to start it from a stopped position and then it up and down shifts on its own like the small car autos? do you push the clutch in when you come to a stop?

Which type are they using in the semi type commercial trucks and which type are they using in the conversions?

Thanks.

[Warpath]

I think you have businesses (racers) who can afford to dump rigs at a lose (business expense) to move on to there next rig. This kills the market for any individual looking to buy a new conversion since he can't afford to take a huge lose in value personally year after year.

What will be interesting is when the economy takes a hit and sponsorship dollars dry up, who's left to buy new conversion.

Just an observation

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Basically there are 3 automatics used in trucks.

The Allison Automatic which is similar to a automatic in a car. Uses a torque converter and has a very smooth transition from gear to gear. (At least the new 6 speed Allisons do)

The Fuller Eaton Auto Shift, which is a manual transmission electronically shifted. This trans requires the use of a manual clutch to start and stop. I believe this would be the tranny in the Volvo your looking at.

The Meritor Freedom Transmission, which is a manual transmission electronically shifted along with the clutch electronically controlled. So no driver input required.

Since the Eaton Auto Shift came on line first you'll see more of these in commercial trucks and for a few years was the tranny of choice in conversions. Meritors trans is now almost exclusively used in conversion and I am sure is now seeing brisk biz in the commercial segment as well.

I am pretty sure Eaton is coming out or already has introduced a similar trans as Meritor. (no manual clutching) And I think I saw where there may have even been some patent infringement by one or the other.

[BravestDog]

Warpath,

Do you know how any of these 3 types of auto transmissions are holding up in so far as durability and longevity?

Do they last as long as a car or family truck auto transmission?

Any idea on what it takes to repair/replace them if they break down?

I can see why the manual transmission is the choice among commercial drivers. Less moving parts and less things to go wrong.

[Warpath]

Your not going to see to many Allison's in class 8 trucks, just not enough gears. But it is used pretty heavily in tour buses. It's a bullet proof trans no issues.

The Eaton Auto Shift has also been out for a while and I have seen very little issue with it on some of the trucker forums I have visited.

Meritor is still pretty new, so not to sure how many have gotten into commercial applications. I haven't heard to much from the conversion crowd about it being unreliable.

The argument that the manual is less to go wrong pretty much doesn't wash anymore. Every diesel motor is controlled electronically, it will shut itself down before something major happens and costs a owner even more money, same goes with a tranny. Would you rather fix a issue before it becomes a complete lose?

The real issue is that your taking away the last real skill a trucker must have to do the job. It use to take a special breed to want to endure long days in a hot, rough riding hard to handle truck. Now a days with 10 hour limits, trucks that ride like a Cadillac, no thinking involved with electronic everything and big sleepers, the pool of drivers just increased bigtime.

[Wick]

I can tell you from personal experience that the allison will take anywhere from $1800.00 to $4800.00 to repair. The Autoshift will cost less but they can be expensive, in the $1500.00 tp $3000.00 range. The manual Transmission can cost between $800.00 to $2800.00 to rebuild. All should go a million or more miles if taken care of. Synthectic lubricants is the way to go with them.
My unit has an Autoshift and it is the 2nd one I have had in a used chassis and I have had no real issues out of either. I think the first one shifted a little better but not by much.

As for Bill's last statement about the driver pool he is right. You now have a bigger pool of drivers out there but if they are just wheel holders then you really do not have a "Truck Driver". Real truck drivers are few and far between........
So do not worry to much about the autoshift it is a good choice and won't kill the re-sale.
Wick

[medent]

Right on about auto shifts increasing the pool of drivers that can handle a big rig and they are not just steering wheel holders as the demands and responsiblities for over-the-roaders is huge, it doesn't end with manual gear jamming, althought that does sort the men from the boys.

The class 8 rigs don't get the Allison torque converter trannys and they get the solid clutch autoshifting trannys when a fleet or owner operator orders them that way. Eaton makes their clutch pedal (used only when starting and stopping) autoshift in 10 speed and 18 speed versions. The 10 speed added about 4000$ and the 18 speed 7000$ to the cost of the rig but Eaton was guaranteeing them for 750,000 miles. Eaton also makes an Ultrashift 10 speed that has no clutch pedal, like their competitor the Freedomline. An Eaton rep told me that their autoshifts are not retrofitable into rigs that came with a standard tranny.

The Freedomline with a servo actuated clutch is made by Arvin Meritor which is a Volvo subsidiary that bought out Rockwell. It is a creation of ZF in Germany and there have been legal challenges between Eaton, Arvin meritor and ZF but I think they have been resolved without putting any of these off the market. Most common Freedomline is a 12 speed but they have offered a 16 speed. My fleet contact says that in spite of the servo clutch the robustness of the Freedomline equals the Eatons; they all can give trouble surprises that you see coming with a standart tranny-clutch set up.

Established big truck dealers now commonly have some mechanics who have been to the mfger's school and getting an autoshift taken care of is pretty doable, just takes $$$. Fuel economy does not suffer like it does with fluid coupling/torque converter transmissions and their lifespan competes well with standards, possibly less prone to driver stupidity/abuse. Probably the less stop & go the service, the better the autoshifts fit in. Torque converter tranny is probably best for stop & go applications.

For an RV the autoshifts make a lot of sense for family driving since they evaporate the need for gear jamming skill but the driver still needs some amount of trucker's intuition.

The Eaton autoshift made a believer out of me in over the road driving and now I've got a Freedomline rig for conversion and it is OK too but has it's differnces in how to best manage it.

Enough of this wind.

medent, El Paso