ok guys looking to upgrade tire to 37's.... in order to keep around the same MPG (i know im gonna lose a little) i know i need to regear the rear diff...
the truck is an every day driver....
2006 F250 4x4 Lariat super crew cab
what suggestions do yall have for me?

 

Gotta do the front diff too, although Im assuming you already new that.

 

yea thats what i ment sorry.... i know i need to regear the entire truck just wondering what size gears would be best?

 

Go to one of the online 4x4 places that sells tires. Usually they have a gear ratio guide on tire size. I think a lot go with 4.56.

Here's a link to a chart

http://www.4wheelparts.com/aux_incl/gear_ratio.html

 

What engine you running?

Prob the best gear for 37" tires...is going to be the 4.56.


Hope this helps...


biz

 

with 4.56 wont i lose top end power??

 

6.0 powerstroke

 

I've heard guys say the diesel's do well with higher gears (numerically lower), but I dont own a diesel so....

 

I attached a link to my earlier post on gear ratio selection. check it out.

 

i was told to look into 4.10's but im just not sure i dont know much about gearing just wanted to get some input from you guys in order to have a better outlook on this topic to make the best decision possible

 

Hopefully a diesel guy can chime in who has a similar configuration.

 

If you are running 3.73, then 4.30 would due well. Try this Calculator...

Calculators


biz

 

thats just it im not sure what im running right now... all i know its factory stock im trying to figure out what i got but im having some trouble

 

No tag on the rear diff? Also check out the SuperDuty tech folder at the top of the threads. I think there is something there to tell what you have by the tag on the door.

 

im deployed right now so i cant phisically look at anything on the truck just doing research for when i get back getting ready to do alot of MODs