01 ford expedition rear end

My parents expedition had a whine from the rear end for a short time and now some of the teeth off of the ring and pinion broke. im guessing its a pinion bearing that was bad because my dad changed the outer axle bearings and that didnt fix it. The tag on the differential says S802L and 31 88 ok12. I looked it up online and it says its a 8.8" ring gear and 3.31 ratio. Is that correct? I told them just to swap out the whole rear end from a junkyard one so they dont have to figure out why it broke. But my question is, would a different ratio make a difference? Just as long as its close to the same ratio it should be okay right? its just a 2wd too, so dont need to match gears. Thanks..Mike

 

Different rear end will change a few things but nothing drastic if the rear end is coming out of another expedition. Bottom line is it will work fine if its out of the same model.

 

yeah was going to get it out of another expedition.

 

Should be fine

 

just asking just incase we cant find the exact same one.

 

since its 2wd the gear ratio wouldnt matter. If i am correct it wouldnt hurt anything, but the same ratio you have in it would be best because that what it came with from the factory. I dont know if they had different ratios in those for different years

 

There is a TSB for rear end noise for that year expedition ...however it does not explain the broken ring and pinion, that is something entirely separate from the TSB

http://www.mombu.com/ford/ford/t-2003-ford-expedition-rear-end-1658083.html