I get a "DO OVER! "

you planning to run interstate? where the speed limit is 65-70+ ?
I'm turning around 1300 at 65mph - for me that s the sweet spot MPG wise, but id much rather be running 72mph at that rpm (to keep up w/ traffic & benefit from better mpg).



 
Afraid my truck is a old girl. But if better rearend ratio was not to much I would look into it ?

What gears are you running and is your trans a over drive ? Also is it a Auto ?

The auto will be a 1 to 1.

As for speed,around here I could never keep up. Some got to be doing 80+ . Think I will just let them go around.

Anybody running Super Singles on the rear ?
 
my rear is geared at 3.21.

the tranny is a manu-mantic - ZF/Meritor Smart Shift - the gearing ratio's isn't known at least to me.
 
can't answer that - I'm sure others here can/will.

How will being at peak torque impact MPG?
How does being at peak torque impact being able to accelerate or demand power to get around someone?
 
From what I have read peak torque + 200 rpm is best. Overall MPG and power to climb . Don't know about passing ? Going to ask the guy who did the 400 swap in the 5 ton.
 
How will being at peak torque impact MPG?
How does being at peak torque impact being able to accelerate or demand power to get around someone?

I was told (by the guy that wrote the article referenced earlier) that peak torque = best mpg.

A modern computer controlled engine could get away with gearing for cruising speed at 1250-1300 rpm because the computer could make adjustments to allow the engine to accelerate in case of passing or a hill.

For an older "mechanical" engine he recommended 200 over peak torque, because he said although you'd get your best mpg at peak torque, you wouldn't be able to "get on top of it" if you needed to pass or hit a slight hill.

I told him I wanted the auto for my wife to drive the rig. He told me that his most important piece of advice, far outweighing anything he could tell me about gearing or hp was to put a Safe-T-Plus stabilizer in it. I don't remember the details but there was some story about a bad crash with the wife driving someone's rig.

Safe-T-Plus info:

 
personally I think that stuff is snake oil - nothing more than a steering stabilizer.

If that think keeps you tracking straight when you blow a steer how the HELL do you turn it when you need to make a left or right?

Keep a firm grip on the wheel & be prepared. I know Ronnie had a steer blow & while it did tear up the fender and aero/skirt he didn't have any problem controlling his and I don't believe he attributed it to any steering stabilizer (I don't believe he has one anyway).
 
Yeah, It's hard to know what to believe... On another forum one driver thought this was more of a problem before power steering was common on big trucks. I've never had a front blowout on a big truck, however all of the blowouts I've had on pickups and cars have been very controllable. I had a customer that told me a blowout took him across 4 lanes of traffic on I-10... who knows?!
 
Worst I ever had in one of my pickups was a rear blow out at 85mph (I was passing a tractor trailer)....uneventful really....eased off the throttle and pulled it to the shoulder and changed it.
 
I had a right front tire blow out at around 70 mph in my MH. It did not create crazy pull or other actions, but I did have to hold the wheel and keep it straight, slowing down and over to the right side edge of the interstate. Fortunately there was an on-ramp and so I was able to get over farther off the traffic flow. Would not call it a fun experience, but it was also not something out of control or unmanageable. If a brake line or other major part was taken out it could be a lot worse. In my case i only lost some wiring for headlights and the flexible flap seal. It did make some scratches on the outer fender from the cords in the tire. Overall I got off without any major damage or repairs required.

Catastrophic failure of the tire, completely blew and shredded, by the time I stopped there was only two rings for the bead with some small sidewall. Rest of tire was all over the interstate, hahaha. Some small scratches on the outer circumference of the wheel, but more cosmetic than anything. I did not have to get a new wheel.

Back on the cruising speed, I could never do 55-60. I usually set cruise at 70-72 and live with the reduced mpg.
 
Taller tires?

To the OP considering different gearing. Have you considered taller tires? They will effectively increase your gear ratio. Higher speed at lower rpm.
 
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Going to stay with the 9 speed and the tires on the truck.

Started some work on the heater.

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It will be under the couch.
 
When you use the 1/4" stuff make sure you put some backing from behind to help hold lights and things.

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