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Oil leak, what the heck?!

From the looks of that pan, it just din't start leaking, its been leaking for awhile, what you need to do is try and isolate where the leak is actually coming from, buy you a can of gunk engine cleaner, follow directions, put your old clothes on, go to quarter wash, prepare to get wet and clean the engine better than  the best you can, then with as much muster as you can, a bright light and a step stool, you'll see where your oil is coming from.

Welcome to the club and enjoy the wealth of information you will find here.

Didit
 
What Didit posted and if you are still not sure. If you are about do for an oil change you can purchase a dye and black light kit from most auto parts. Ive used them saves time, headache, and blood.
 
Mines a 1500, different animal, but I had oil leaking down my oil pan as well.  I thought it was the rear main seal with is expensive... it ended up being the valve covers which isn't as bad...  I could have DIY'd those, but I had no idea and needed help sourcing the leak.  They found it, so they got the money... lol



 
I emptied a whole can of engine degreaser over the course of several hours and welding wire brushes on the oil pan. It's clearly leaking up higher, what would typically leak on the back of the motor?
 
My 2013 was leaking up high and running down the back of the motor, and it turned out to be a valve cover gasket.

At 20k miles....
 
Hopefully it's a valve cover gasket as that is pretty simple.

If not that hope for at the oil pressure switch (sending unit).

Then the most likely candidate is the rear crank seal, which would take dropping the transmission to get to...
 
If it's the rear main, you might get lucky if you use Valvoline MaxLife motor oil on your next oil change.
I had a Firebird that would drop a good sized puddle on the ground when parked, after driving on the highway for an extended period.
The MaxLife helped dry it up some.
That car ended it's life when I got hit by an impaired driver.
If somebody ever hits my 2500 Avy, there will be trouble!!  :beating:
Anyway, good luck with it. Hope this helps!

CarMech1969
 
leaks are hard to trace in that area.  I have heard that if you have a rear main leak, it leaks *a lot* of oil.  And keeps getting worse.    If you only have a little oil, I would bet its the valve cover gaskets or oil pressure switch. 

Buy a new switch first... they are only like 20 bucks I think and you can swap it in 5-10 minutes. 
 
I have the same problem, i have an 02 with 304k miles. Just recently i had my trans rebuilt for the 2nd time, so when the trans was out i had the main seal replaced. Still leaking. Going to search for a thread about the switch. Did you find the source of your leak?
 
I had a rear seal go on my 4 CYL '94 S10 at about 20,000 so under warranty. They said it was a known issue.
They had better than OEM seals in stock for that engine and hasn't leaked again in 20 years.  :B:

My '94 was first year of a new model S10 but not sure there were major changes to the engines.

One thing I saw many times over my 30 years at GM is for the bean-counters to substitute cheaper parts. A few pennies here and there add up to big bucks over time. They could have went to a cheaper seal then switched back to the tried and true one after they discovered a few leaks.

They don't warn the customers as warranty will expire before most leak.
 
sorry this is almost a worthless update, but I have a new neighbor who is a driveway mechanic and is pretty knowledgeable, I know enough to know if he was BS'n me anyway

I mentioned the suspected rear main seal leak and he got to thinkin about it and has some ideas, welp I sold my Sierra today- bittersweet cause I loved that truck but my needs outgrew it and I was happy to have no more vehicle payments so now my focus is on the AV exclusively

the nabe has done some research and there is a small chance its something other than the rear main but it is leaking fairly aggressively for an oil leak so could be the seal

I've yet to remove the protective plate that guards the rear main to clean and confirm where the leak is coming from but it will be soon (read- this weekend), now the the AV is my primary "cage" I want it tip top and leak free
 
supermanotorious said:
I've yet to remove the protective plate that guards the rear main to clean and confirm where the leak is coming from but it will be soon (read- this weekend), now the the AV is my primary "cage" I want it tip top and leak free
Click to expand...

Do you know that "the protective plate that guards the rear main" is usually referred to as "the transmission"?
 
Well, that sounds like it may be a skid plate.

Anyway, a plate connected by 4 to 6 bolts is a lot easier to remove than a transmission but you aren't going to be getting a good look at the rear main seal without dropping the tranny.
 
if you have an air compressor, an air ratchet is really handy when taking the skid plates off... 
 
the plate I'm referring to guards the torque converter and starter motor gears

I couldn't take it all the way off without dropping the exhaust but I moved it to where I could see the bottom of the main, I'm almost certain that's where it's leaking from
 

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