niceguy88

Well I've noticed over the last week some small oil leak spots under the passenger side of the van and after some inspection it appears to be the oil filter adapter gasket, a seemingly fairly common issue on the 3.5/3.9. Plus I'm at around 158,000 miles.

It looks like a pain with the rounded plastic/metal subframe so close so does anyone have any tips or experience removing the filter adaptor and replacing the gasket?

Thanks!

Jeremy

niceguy88

Nevermind, I replaced it this morning. Seems to be a common issue with 3.5/3.9s at some point. The gasket simply has a lifespan and eventually fails, like the common coolant crossover pipe gasket (had a mechanic friend do that one, wasn't touching it!).

There was an unexpected mess as the Uplander 3.9 has an oil cooler built into the the filter adaptor (due to having piston oil squirters). I was aware of this but not the near gallon of coolant that poured out after removing the 2 coolant lines from the adapter. Fortunately I had old newspaper and an 18" roller pan laying nearby in the garage.

Hopefully I'm good now, but the entire undercarriage was heavily coated in oil and only a few drops were manifest on the driveway initally. We'll see...

BTW, here's a link that may help some to get an idea visually of what to expect but you don't have to move the AC compressor.
http://www.impalaforums.com/diy-how-...00-3900-a.html

Jeremy

Papa Bear

Great info, Jeremy. It may come in quite handy for a few or us as time goes along.

Lgt1733

There's a video on Backwoods Mechanic's Youtube channel where he replaces this gasket without losing any coolant. Did you remove the coolant lines for better access? Hoping it's as simple as BWM's video, I don't want to make a big mess with coolant. I think there's also a video on Youtube where someone loses a bunch of coolant doing the same thing, so I'm hesitating on tackling this replacement.