The VIN decoder stated that there is a 3.55 minimum to 3.92 maximum on this truck. I need to replace the rear differential. Can I put either of these in the back or do I need to match the front? If I must match the front axle's ratio how do I definitively I.D. what is up there.

 

Front and rear absolutely MUST be the same gear ratio. The stock ratio should be listed on a sticker, I think under the hood somewhere. Either that, or you can get a build sheet, and that will tell you what it came from the factory with. If you think someone has been in there before, then the only SURE way to know, is to pull the cover, and have a look. Gear ratio (or, tooth count) should be scribed on the ring gear somewhere.

Welcome to DF!

 

Thank you very much that really helps. It verifies information I had received concerning a sticker under the hood so I will look for it. Thanks again

 

You can put a different ratio in but then you have to remove the front driveshaft so no more 4wd. Works in a pinch. Or when regearing to save up.

 

If your front differential hasn't been messed with there should be a small silver tag under one or two of the cover bolts. You might have to scrape some grim off the tag before you can read it.