I've been looking around for a half hour and can't find answers... Sorry to be the squeeky wheel.

1) I own a 2000 4.2L XLT. What's the stock gear ratio on my truck most likely to be? I checked the diff and someone mashed the tag so it's illegible.

2) Plopped a set of 265/75/16 BFGoodrich All Terrains on today. They look damn pretty! They are also about the most heavy tire on the market due to the reinforced sidewalls and heavy tread pattern. Based on wheel size and stock gear ratio... will the stock gears be able to handle these tires or will I chew them up? I only street drive so there is no extreme off-road beating placed on the truck.

3) If the stock gears aren't good enough... then what would be a good recommendation for my usage as a daily driver (downtown Chicago) and occasional highway usage for road trips? I'd like to still make decent gas milage considering I'm still pulling the 16/21 factory sticker at 100K but I don't want my truck to putt-putt down the road either.

We really ought to post an FAQ for the diff's with tire sizing and if there is already one and I didn't see it... just call me "********".

 

Is there a tag inside your drivers door on the jamb? If so look for a code for the differential.

Your tire selection is not going to chew up your gears.

 

Question 1) ANSWERED!

After searching around for almost two hours I found a page in here that had a description of identifying gear codes. I'm pretty sure I'm a "one wheel wonder" with a 3.08 to my name. I was pretty sure that is what the truck had but wanted to know for positive.

Question 2) ANSWERED!

Thanks Dr. Franko!

Question 3) Pending...?

Still considering gears... Would I be best off with the 3.08 or should I consider a 3.31 or even possibly a 3.53? Or should I just leave well enough alone?

 

What was you factory tire size? More than likely you have 3.55's already in your truck. My previous truck was a 2000 4.2l XLT extended cab it came with 3.55's and 255/70/16 tire's. I upgraded to the 265/75/16 and changed out the rear end gears to 4.10, after the gear swap I was still getting around 17 to 18 mpg on the highway.

 

i wouldnt regear with that small of a tire increase not worth the cost of parts / install