Have a 5 speed 4.6 running 33's. I currently have the stock 3.73 gears in my truck and I am thinking about switching them. Would I see much difference going with a 4.11 set or 4:56 set? Which would be best?

 

It's not really necessary to regent unless you need power to tow with 33"s

 

You should be alright with 4.10 but if you think you'll ever get bigger tires just go with 4.56

 

I am running 315/70/R17 and i was wondering would regearing help my gas mileage any. I'm getting at most on highway is 14 mpg and in town around 10 right now my truck has 3:73 gears

 

I don't think so

 

I was just thinking the bigger tire has a bigger circumference so a gear swap say a 4:11 would bring that back closer to stock wouldn't it? I dunno it's all Crazy to me some people tell me it will help and others say it won't

 

All things being equal, the lower the engine RPMs you are turning, the better your mileage will be.

So, if you are running 35" tires, 4.10 gears should give you better mileage than 4.56. However, sometimes smaller gears will make the transmission downshift more, which increases your RPMs, which decreases mileage.

The larger number (lower ratio) gears do not make any more power, they just make you quicker off the line. Guys running large diameter tires would be bogging down off the line, if they did not also change the gears. Also, their tranny would be downshifting all the time.

With a set of 35" tirs on a truck going down the highway at 65mph in OD with the TC locked....


3.73 = 1630rpm ....

4.10 = 1790rpm.....

4.56 = 1990rpm...

4.88 = 2132rpm...


Now, depending on what motor you have and your towing/hauling habits are, the decision should be easy...

A 4.6 is going to need a few more revolutions than a 5.4....

And its just not the size of the tire, its the weight of them...


I personnally... would go no less than a 4.56 with a 35" tire....

If your paying good money to do a swap, make it worth while IMO.

Good luck .