Diff question

[gobblegobbler]

So I know a bit about working on cars, not much, but enough to do some basic maintenance myself. The previous owner said that he serviced the diffs but wasn't sure if he put the fuild in the fill or breather holes. First, I have absolutely no idea how someone manages to miss that, but anyway. He said he continued to drive it after that and had no problems. I'm not too convinced of this, so my question is does this cause any problems? If yes, then should I try to source new diffs?

 

[Emperor Paul_]

If he used the breather instead of the fill hole, the diff might be underfilled, risking wear, you can drain and refill properly first, check for metal shavings, I don't think replacing diffs is needed unless it is damaged

 

[forestbeastmode25]

Could also be the opposite. Filling fluid into the breather hole can be a significant problem. It leads to overfilling the differential, which might cause seals to blow and potentially damage parts due to too much pressure and heat.

 

[Toolfriendly]

I can understand your situation, but don't rush before making sure everything is good. A failing diff will sound bad, whirring, whining, all the bad noises when metal is scraping on metal. If you don't hear those noises, you can do a full diff flid change, get right hole and drive worry free. On the other hand, if you've been hearing these noises, then you'll probably need to start thinking about new diffs.