Oil Leak

wontwork · November 28, 2007

I am new to the site, but I can already see the benefits from it. My problem is I have 1400 miles on my truck and it is already leaking oil. The oil is coming between the trans and motor and it is definately motor oil. Has anyone else had this problem, if so what was the cause and fix to it. I want to be prepared when I go in to get it fixed so they don't try to dick me around. Any help will be greatly appreciated.

VMax2007 · November 28, 2007

Yep, common problem. Most likely the rear seal and/or the crank position sensor o-ring. do NOT let them tell you it's the oilpan. It could also be the oil cooler line block manifold.

See this link: http://www.gm-trucks.com/forums/index.php?showtopic=67327

There are pics.

wontwork · November 28, 2007

Thanks for the help. I will get it checked out.

wontwork · November 29, 2007

Going to get it fixed Monday. Thay said they had a few come in, but it ended up just being an oil pan.

You can tell from where my oil is coming from that it is no the oil pan though. They looked at it and said it could be the rear main, and that they would fix. They were supper nice about it and was even going to give me a truck to hall my rockcrawler this weekend, but they didn't have a truck setup for towing that was a loner. All in all it is going to get fixed. Thanks for the help.

VMax2007 · November 29, 2007

Going to get it fixed Monday. Thay said they had a few come in, but it ended up just being an oil pan.
You can tell from where my oil is coming from that it is no the oil pan though. They looked at it and said it could be the rear main, and that they would fix. They were supper nice about it and was even going to give me a truck to hall my rockcrawler this weekend, but they didn't have a truck setup for towing that was a loner. All in all it is going to get fixed. Thanks for the help.

It very well may be the rear main seal, but it's NOT the oil pan, I would bet my truck on it. However, I would seriously have them check/replace the crank position sensor o-ring first since that is a much easier, cheaper (for them) and less intrusive fix. After 3 tries, that's what finally stopped my oil leak. I am still not even sure the rear main was ever leaking and I know the oil pan wasn't. Not sure if the oil cooler line manifold ever leaked either?

Huntervh · November 29, 2007

Yea, same problem with my truck.

Just took it in last week to have it looked at, they replaced the oil pan gasket. Just waiting for more buildup of oil to take it in again, cause it is still leaking.

C & A s Dad · November 29, 2007

Where is the crank positioning sensor located? Just wondering if it can be easily seen.

VMax2007 · November 29, 2007

Where is the crank positioning sensor located? Just wondering if it can be easily seen.

Above the starter. If it's leaking, you will see the oil drips on the starter bolts and in that general area. it will also migrate down to the bottom of the bell housing (lowest point).

Zembonez · November 29, 2007

Where is the crank positioning sensor located? Just wondering if it can be easily seen.

Above the starter. If it's leaking, you will see the oil drips on the starter bolts and in that general area. it will also migrate down to the bottom of the bell housing (lowest point).

WOW... that's what I call SOLID information. If there is any doubt after that great picture... I give up!

C & A s Dad · January 18, 2008

I have just gone back and found where you answered my question on the CPS location. I am seeing a very small amt of oil at the bottom of my bell housing and did find some on one of the starter bolts. I have wiped it off and it always comes back after a hundred miles or so. It is not enough to drip but just enough to worry the crap out of me.

I have removed the inspection plug in the bell housing and there is no oil inside the housing, on the flyhwheel or torque convertor. For this reason, I all but ruled out the rear main seal. You would think if the rear main was leaking it woudl be wet inside the bell housing.

As soon as I get back home I am going to check the crank pos sensor. From the info you have provided and the picture, this looks like my problem.

Anyone else see this type of leak?

I have an appt at my Dealer for Monday to take a look. My ext warranty runs out in less than a month.

cjtreibel70 · January 18, 2008

why is it that so many people forget that there is this wonderful thing called a WARENTY that will fix it for FREE!!!!!!!!!!!!!

C & A s Dad · January 18, 2008

Sometimes it is not really convenient to take a vehicle in for a day or two. For me, if it is something like the CPS o ring, I will fix it myself. If it were something like the rear main seal, I would take it in for a professional to fix.

cerbomark · January 18, 2008

i had oil on the starter like Vmaxes pic and also down at the bottom of the bell housing. Mine was the CPS sensor. It s buried somewhere on the rear of the motor. I couldn t find it.