Canadian Hummer Club Forums

Hummer H2 has been leaking oil ever since switching to Synthetic oil. Should I go back to regular oil will this resolve the leak or should a seal or gasket be replaced?


Anyone experience this or have any ideas on what would cause the oil to start leaking after switching to Synthetic?


Looked underneath and the leak is near the differential crossmember bushing. The cross member bushing is covered in oil everything else looks fine with no leaks

It simply means that your old seal should have been leaking but the old oil was too thick and full of crud for it to leak. The lower viscosity synthetic and the cleaning properties of the new oil simply made the leak that would have been there visible.
 
Replace the seal and you will be fine.

True dat aka polar bear:)

I'd first look at where originating from though, once I changed oil and filter didn't go on tight enough so small leak,

Or I know it's a temp fix ,but I do love me my "Lucas engine stop leak, " it will prob find your leak and swell up gaskets.

I use in my diffs as well

Turned out to be the oil pan bolts were extremely loose . There is some seepage from the top in which was cleaned off today and I am to go back in a couple days so they can locate it. But for the oil that was leaking it was due to the oil pan bolts.