06 Escalade oil leak rear of engine?

[drhill]

Hi Everyone,
I have a stubborn oil leak at the rear of the engine in my 2006 Escalade. I just replated the oil pan gasket with oil cooler gasket, timing cover gasket, valve cover gaskets and did a new oil pump and o ring and water pump while I was in there. The flexplate and torque converter area was clean and dry when I removed the plastic covers. Drips are dropping from the rear starter bolt on the passenger side, the rearmost pan bolt on the drivers side and it appears on the bottom of the bellhousing. Is there an oil sending unit on the back of the block somewhere? Doesn't appear to be form the rear main seal or the rear cover - wouldn't there be oil on the flexplate etc if so?

Thanks for the help!

 

[MassHoe04]

Oil pressure sensor is at the back of the engine block, practically above the flywheel at 12 o'clock position. Could explain oil dribbling down both sides. The OPS is a fairly common thing to leak or start giving bad readings with old age.
See if you can get a little inspection mirror over the top of the flywheel area (or one of those colonoscopy camera probes) to see if that is leaking.

 

[Scottydoggs]

sounds like a rear main seal. trans needs to come out to change it. not a cheap or esay job for a 8 dollar seal.

 

[MassHoe04]

I posted link to Silverado forum with similar described leak. But that turned out to be a Detroit Diesel motor...
Disregard.

For what it was worth, though... The Detroit Diesel was drippy on the bottom of the bell housing, but inside the bell housing and torque converter area were bone dry, like yours. His leak turned out to be oil pan gasket.

 

[rockola1971]

OPS is where it has been for over 50 years now. Right behind the Distributor.....or in our case on the LS series engines.....right behind where the distributor would be if we didnt have distributorless ignition (DIS).

Not uncommon at all for the OPS body to develop a leak and start puking black gold down the back or passenger side of the block. Wipe it good and clean around the OPS and go for a drive and check if its wet with oil.

 

[Fless]

Also the cam position sensor is right next to the OPS.

 

[drhill]

ok I'll check out the OPS and Cam PS areas. Someone had mentioned the valley cover in an old thread I found?

 

[OR VietVet]

My vote is either the OPS or the cam sensor leaking or back of valley cover BUT, you may have actually been fixing the correct leak but may have had a faulty part or may not have sealed it correctly and is still leaking. I don't know your mechanical abilities and am not pointing fingers and is why I said MAY, but it does happen. Also, can still be leaking at rear main seal assembly because the oil does not ALWAYS leave the trail you expect to see at the flexplate and torque converter.

When I have had or seen leaks that have leaked long enough that so many spots that could be leaking, are covered with oil from oil leak being blown around from turbulence under the hood and then it turns in to guess work. I like to completely clean and dry and drive and look again and/or use dye and a blacklight. That efforts time and money could have easily been covered by the time and money you have spent so far and then if you choose to go deeper, that is a choice instead of an attempt at a guess.

 

[drhill]

My vote is either the OPS or the cam sensor leaking or back of valley cover BUT, you may have actually been fixing the correct leak but may have had a faulty part or may not have sealed it correctly and is still leaking. I don't know your mechanical abilities and am not pointing fingers and is why I said MAY, but it does happen. Also, can still be leaking at rear main seal assembly because the oil does not ALWAYS leave the trail you expect to see at the flexplate and torque converter.

When I have had or seen leaks that have leaked long enough that so many spots that could be leaking, are covered with oil from oil leak being blown around from turbulence under the hood and then it turns in to guess work. I like to completely clean and dry and drive and look again and/or use dye and a blacklight. That efforts time and money could have easily been covered by the time and money you have spent so far and then if you choose to go deeper, that is a choice instead of an attempt at a guess.

You are right, things happen and sometimes the repair does not work if you rush it don't prep surfaces etc. Always appreciate input and advice from an ASE guy. I was starting to see the signs of a bad o ring seal on the oil pump pickup (low oil pressure at idle etc) so between that and the oil leaks I figured it was time to go in and fix a few things. On a 200k mile engine that is covered in sludge, I'm happy to spend a few $$ fixing leaks.

I did clean everything as best as I could during the repair work and once a saw a small leak after the repair, it was finally clean enough to see the general area it was coming from. I know this engine had multiple leaks and I know I took care of a few of them already that have not returned (valve covers and timing cover/balancer seal). If it's the rear main or rear cover, it's gonna stay until the trans needs a rebuild. But I'll check rear of motor by the 2 sensors and the valley in the morning when it's cool and see what I can find.

 

[MassHoe04]

After owning a number of older cars, trucks and SUVs...

I have learned to observe what things look like on a normal day and keep an eye out for the differences between the "slow daily weep-age" and what might be a "new critical leak".

After a while you become de-sensitized to the normal weeps and drips of an old vehicle and stay alert for leaks that could soak an alternator, starter, belts or other critical components.

Obviously repairing serious things needing attention, but doing so when it makes sense and I can afford it.

Anyone who has been accustomed to having only new vehicles, restored show cars or OCD... Then, I can see how what might be "acceptable" for some folks on old daily driver might be a really hard to not stress about leaks popping up here or there.

If this were mine and was an easy and cheap fix (like one of those sensors), I would go for it. As OP states, if it is the RMS... I would hold off until the tranny HAD to come out.