: Lt1 oil leak, rear intake seal?

05-03-11, 10:50 AM
So i have an oil leak on my -95 fw, afaik it started after the last oil change. Drivers side cat, oil filter and the cover behind the oil pan is dripping slowly when the car is running.

To my understanding this could be rear intake, oil pressure sensor or head cover gasket. With rear intake the most probable cause. lot of dirt but it also feels like quite fresh oil when i reach Down behind the intake.

I Will begin looking into this tomorrow Any suggestions for things to look out for or Any other possible causes for rear oil leak?

05-03-11, 04:36 PM
I would check on the oil filter extension gasket and O ring
if its dripping off the filter thats most likely the cause
and its very common
also check on the oil cooler lines that run from that filter ext.
I just replaced these items on my low miles 95 fwb
and it cured the drip 100 %
in my case it looked like the rear main was leaking
but it was just the o ring and gasket
check the rear of the intake as well another common place to leak oil

05-03-11, 05:11 PM
Thanks for the input! I'll look for that tomorrow when i Jack the car up. It'd match With something happened when i changed the oil filter also the first single drop i saw was on the oil filter.

05-04-11, 05:09 AM
Update, you were correct fleetwoodguy! the oil is coming from where the filter adaptor meets the engine block.

I also took closer look behind the intake and it sure could use reseal but I'll leave it for now since it's only slightly oiled behind and it also feels like mostly layer of old dirt and just a tad oil. Thanks!

05-04-11, 12:53 PM
88893990 oil Filter Adapter Gasket & O-Ring.
use the two piece kit, the old gasket can be a pain in the
ass to remove, you will need a few new razor blades
the new gasket has a metal backing to it to aid in removal
next time around, it helps to unbolt the oil cooler lines from the front of the engine frame so they can move easily (1 bolt) otherwise you might end up slightly bending them at the adapter, which will make it hard to align during re assembly, not a bad job all in all good luck glad we could help........Jim

05-04-11, 02:23 PM
Luckily my local gm parts dealer had the two piece kit on the shelf. I also got new washers for the oil lines so now I'm set for a dirty weekend with my fw, fsm and also torque wrench. Just got to get the razor blades. :)

05-07-11, 02:43 PM
I'll throw in small update if someone reads this and is about to do the same operation.

Get some gasket remover too, the gasket was real pita to remove. Even with the remover, but with only razor blades I would never have gotten it off. Hard as rock. But now the car isn't leaking anymore, quite quick fix except for the gasket which took me half day to slowly tear down.

[Edit] gasket remover + eye = do not.