hi all - not a post i am thrilled to make here haha. my front end has been making noise for the last few days and when the shop looked at it, it seems some water has gotten in the front diff and the axle seal is leaking. the shop is fixing the axle seal tomorrow and doing a drain/fill on the front diff, but they are not confident the noise is going to stop. it really isn't too bad, mostly a whoom-whoom-whoom sound as i get up to 20mph or so. i have the 4wd v8 so the front diff is engaged constantly. the noise only happens under load and they are confident the problem is inside the diff. my front wheel bearings have been replaced recently so we've ruled that out.

the shop says the vehicle could possibly be driven for years like this and the diff is unlikely to grenade (thoughts on this anyone?). that said, i would like to get it repaired. i've been going through the forum for a few hours and the shop isn't able to say conclusively what is wrong without starting to tear things apart.

i can source a front diff rebuild kit on rock auto for about 300usd. the shop estimated a 7 hour rebuild job. but i've been getting some feedback from various car friends that it may be easier and cheaper to just find a used front diff.

i am wondering how i would go about sourcing something like this and how do i know if the part is compatible? is there a certain salvage website that everybody uses for this type of thing? are front diffs from other vehicles compatible with my 4runner? i'm in canada.

thanks as always