What is the gear ratio i am going to want if i go to 35" tires with the inline 6, or wont it push them, i'm not sure. Thanks

 

do you want high-speed highway driving, or quick off-the-line acceleration/efficient for city driving?

 

4.10s or even lower- maybe a 4.56 set to put it close to the 'stock' ratio. Unless you are willing the work yourself, and a lot of guys arent, it's about $300-400 per pumpkin for labor and another $200+ in parts. So it's gonna cost at least $800-1,000+ to regear. It's not cheap.

You can put 35s on it with 3.08s/3.55s- but it won't move out well, it would be really hard on any auto tranny and you probably couldn't hold speed going up freeway inclines.

 

Hi all, similar ? sorta -- I have a 91-F-250 XLT 2-WD w/460 motor. Truck is lifted 3" and I want to run 315-75-R16 pro comp XT so will this work? or not ? I am new very newwwwwwwwwwwwwww to American HorsePower, I used to drive a 71 VW panel Bus (40-horse) LOL . So Just call me Big Dummie - I want to learn and appreciate any help here ! Best all , B.D.

 

The six makes a lot of torque, so don't worry about it not being able to move the truck.

You need to tell us what tranny you have. Whether it's an OD tranny or not makes a huge difference in the answer.

 

still I would go with the 4.10's for the I6. and andy is right, the tranny makes a big difference. The I6 also can't rev very high, so if you go with the 4.56 or more, you may run out of speed fast.

 

hmm.. I have 4.9L I-6, M5OD, 29" stock tires and 2.73 gears. Even thought 2.73 is lowest you can go, my truck takes off the line quite well, and is a rocketship on the highway in terms of top speed (peg the needle and only do 2250rpm! in 5th/OD).

So if I was (and I am!) upgrade to 35" tires, I'd calculate like this:

35
-- * 2.73 = 3.29
29

So in theory, I could have the same performance only upgrading to 3.29 gears with such a substantial tire upgrade.
But one should take into account the rolling mass of these bigger tires, and more drag possibly with a taller truck with wider wheels. So one could make a slight increase in gear going to a 3.55.

So if one is a highway/city daily driver, then I'd think 3.55 would be a good combo. Obviously if one does offroad and city driving, a much higher gear is essensial

 

I had 3.08 gears in my truck from the factory. With stock tires they were ok. Then I put on 31's with the stock 3.08's. The truck was a DOG!! I then desided that I wanted a locker in the rearend, so I desided to do a gear change also, I went to 4.10's and also up graded to 33's. Now the truck has good power, but I am going to put 31X11.50's on for my next set of tires. Then I feel that will be the best combo of pulling power and also highway driver. I personally will never buy a truck with anything higher than 3.73's again, once I found out the performance differances of lower gears.

If I were to run 35's I would go with 4.56's. You have to remember that with bigger tires not only the diameter inceases, so does the wieght which puts alot of strain on the motor.

BTW, for a Detroit Locker in the rear, new ring and pinions F/R, bearing and seal kits F/R, new front carrier, and labor I spent $1600.

 

and to add to phs79's motor srtain comment, upgrading your brakes is a smart move as well.