I have an oil leak in Yukon with 277,000 miles. I'm not sure if it's coming from the rear main seal or the rear part of the oil pan gasket or if there is a gasket at the oil filter adapter. The rear main seal was changed with a NAPA brand at about 245,000 miles when I put in a reman transmission. I cannot pinpoint where the leak is coming from even after power washing it clean. I'm losing about just over a quart of oil every 3000 miles. The oil seems to be dripping right where the oil filter is even above it, I just change the oil today too. The whole oil filter is usually soaked as well as the bottom bell housing of the transmission . Last oil change prior I swapped out the oil cooler block off plate gasket with no effect. Has anybody had any issues like this? I'm tired of the large oil spot on my driveway, but I don't mind the rust proofing underneath the truck, LOL.
Oil leak
- Thread starter Merc1973
- Start date
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Sam Harris
Supporting Member
I think the dipstick o-ring is a common culprit after doing certain jobs on the truck. Certainly installing a transmission, given the location. I’ll look for a thread..
adventurenali92
Full Access Member
I just had my oil pan gasket done along with the oil cooler block off plate. Three months later it was still leaking. Turns out my valley pan gasket needed to be replaced. That’s actually getting finished up as we speak. It’s coming from the top of the engine and dripping down over the oil filter. Could be the culprit on your truck.
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Merc1973
Full Access Member
Wow, really? It was either one or two years ago I replace my intake manifold gasket and knock sensors and harness. That was a big job oh, so I guess I have to do it all over again to get to the valley pan gasket?
JonnyTahoe
Full Access Member
Welcome to the "My Truck is leaking oil" club. I have been chasing a leak off and on for months. I too replaced the Block Off Plate with no luck. I have tried many different types of oil and they do seem to help but oil alone is not going to stop the leak entirely. High Mileage Conventional oil seems to help. Not even going to worry about it my oil pressure is perfect the motor runs great and cardboard under the truck is Free.
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Oil pressure sensor could be leaking as well.
JonnyTahoe
Full Access Member
Had it for months on a shelf in my parts dept in the basement. Thanks Mark you got me motivated to take the fifteen minutes to install it.
Hope it fixes the leak!
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Merc1973
Full Access Member
Wait you said 15 minutes? Is it possible to get the special socket back there on that without removing the entire intake?
