Outer Limits 4x4 Board

Hey guys... noticed some oil spots on the driveway so took a peek under the zuk and saw the rear diff is leaking a small amount of oil.. it appears to be coming from both the plug facing outwards as well as the downwards one... its just a super slow drip, but its wet with oil at the bottom (buildup).

Any ideas whether its serious? or is it just another zuk thing? =)

i used to have that on my vit. the drain plug should have a good seal and shouldn't leak at all, but the filler plug on my vit diff has a copper washer to seal it. all i did was get a new washer, (and a new plug, old one was rooted).

i dont know if the filler plug on sierras are the same. have you checked they are tight?

or, drian the diff, and get new plugs for filler and drain. make sure thread is still good and clean on both.