Since I'm really tired of blowing 5th gear all the time, I was wondering if changing gear ratios would be the key.

Here's the idea.....

I've currently got 4.10's, and I run 235/85-16's. and in 4th gear, I can only run about 60mph, or 65mph tops. How about if I were to change the gears to 3.55's and forget about 5th gear all together, and just run forever in 4th gear ??

What speed / RPM's would I be looking at safely ??

Is this even a good idea, or am I off base ?? 95% of the time I use this truck, I'm pulling a loaded enclosed car trailer, and now upgrading to my new 48 footer, I know 5th gear isn't really even an option to use anymore.

Your feedback would be greatly apprectiated,

Thanks !!!

P.S. Why is it that I get the same, if not better fuel mileage running in 4th, than 5th anyway ?? Weird to me.......

 

Driving a narrow-powerband diesel with essentially a four-speed transmission (one of which is a creeper!) sounds to me like a certain recipe for driving misery.

justin

 

if you get better mileage in fourth what are ya doing in fifth? if you go to taller gears in the rear it will put more stress on the tranny, lower gears would be nicer to the tranny.

 

Maybe go with a taller tire. That would help quit a bit. Maybe you could keep it out of 5th. I run 315's on the stock lift. They are very close. When new they rubbed a little. At 65 mph I only run 1600 rpm. My speedo is off by 10 at that speed. I checked it against my GPS.

 

Maybe go with a taller tire. That would help quit a bit. Maybe you could keep it out of 5th. I run 315's on the stock lift. They are very close. When new they rubbed a little. At 65 mph I only run 1600 rpm. My speedo is off by 10 at that speed. I checked it against my GPS.

 

I would suggest getting your 5th gear fixed properly........there is no reason why you should be blowing your 5th gear continuously........updates have fixed the problems long ago.......I would not even consider driving a 4 speed .........you have tons of torque - use it!

 

235/85/16 tires with 3:54 gears will put you at 2425 RPM's in fourth gear.