i just put a new rear output seal in my np231 transfer case and a new pinion seal in my Dana 35 rear and both seals are still leaking, the transfer case seal is leaking WORSE than it did before. i overfilled the diff a little so that might explain why its leaking but why did my transfer case go from a tiny leak to slinging oil around enough to get it on the exhaust. please help

 

did you put a little grease on the seal edges,is there a little rip maybe

 

 

this is the seal i put in http://www.autozone.com/autozone/par..._0_10492,10498

 

Well there's your problem right there.

 

is that the wrong seal? it says its for the NP231 rear output seal but it did look a little larger than the original seal. should i go to napa and get a different seal? also would overfilling the diff cause the pinion seal to leak?

 

bump

 

Sorry, I was making a joke because you bought it at Autozone. Most of the parts you buy from there are crap.

 

well i did some searching and only the dealer carries the proper rear output seal for 95 xj with the np231

 

Like jeepindan said it could be there is a groove worn in the yolk and its not making a good seal. Rule of thumb if you run your finger nail across it and can feel the groove catch your nail then it will leak. Seen it hundreds of times. just my 2 cents

 

i'll check that when i redo the seal

 

well my diff seal still leaks, i think i nicked the surface last time i had it out, oh well, i can live with it. but i finally got my transfer case to stop leaking, turns out i had the wrong seal. FYI: if you're replacing your transfer case rear output seal on an np23j t-case, use napa part #NOS-14978 and NOT autozone part #2506