Oil Leak Into Cab

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YakkoWarner

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You just reminded me of something that I always wondered about... and you answered my question too! So maybe 20 years ago, Chrysler put out an updated oil pressure sender pigtail for a lot of their mid and late 90's cars. They had problematic and leaky oil senders. But anyway, the updated pigtail had a tiny little hose coming out of the connector. I always wondered "how the hell is that supposed to improve anything"? I thought it was really dumb.

But now I know why! That hose vented the leaking oil and kept it from pushing up the strands of the wire and ruining it. Of course, I guess it still didn't matter much because those cars were terrible with underhood wiring anyway, lol.

I had a 1992 Escort (essentially a rebadged Mazda) that had the speedo cable wicking oil into the panel and down onto my leg problem once. Never seen anything like that before.

And of course anything British just leaks oil as a matter of principle. My current 1970 British project drips oil on the shop floor (4 to 6 drops a week apparently) despite not having actual been run in well over a decade and the engine being dry for that time (its the transmission thats leaking and replacing the gasket likely to be the issue would involve splitting the entire transmission casing, for 6 drops a week I'll live with it for now).

My parking space under my Suburban used to look like a crime scene from transmission fluid until I replaced the vacuum modulator, now it just looks like a bad circular saw accidedent happened under there.
 

Scribbles

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Hello everyone, I’ve got an 1986 GMC K1500 with an oil leak going into my cab under the dash right in the center. Yes! It is oil not coolant or tranny fluid. Does anyone or has anyone ever come across this issue? I have no idea how this happened and I have never heard of this before. Thank you for your time
I had this problem in my van and it was a blown head gasket. The oil flowed into the heater core and blew a hole in it then leaked into the cab.
Probably shouldn't trail an overloaded trailer filled with music equipment and 5 sweaty dudes up into the Rocky Mountains to play a concert at a skate park, just because.
 

cornholeeo

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Every 671 I've worked on leaks, if it didn't you may be out of oil.
good point, i was going to suggest to drain the oil and run the engine to see if the leak was still there, instead of crawling under the dash. JK
 

JBswth

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Every 671 I've worked on leaks, if it didn't you may be out of oil.
That's what they used to say about Harleys - if it doesn't leak, it is out of oil.

J. B.
 

kenny68chevy

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If you have an electrical oil pressure gauge and it is leaking oil inside your truck under the dash, your oil pressure sending unit is bad . The electrical current will pull oil through the wire all the way to your oil pressure gauge. I have seen this only a few times and I have been a mechanic for 45 years .
 

Ricko1966

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If you have an electrical oil pressure gauge and it is leaking oil inside your truck under the dash, your oil pressure sending unit is bad . The electrical current will pull oil through the wire all the way to your oil pressure gauge. I have seen this only a few times and I have been a mechanic for 45 years .
Covered back in post 8 and 9. Yep, it's not common,but it happens. I fully believe that the oil is pushed, by the oil pressure and uses the wire as a hose. The cars with spade connectors, when the sender goes bad the oil just drips at the sender. Its the ones with molded rubber boots that push oil into the interior. Nonetheless it does happen. It happens with coolant senders too. Looks like you're new around here. Welcome!
 
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