Leaking rear main seal

Drivetrain discussion including Transmission, Differential, Driveshaft, and related items.
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mikem85
Posts: 11
Joined: Wed Jan 01, 2020 5:19 pm

Leaking rear main seal

Post by mikem85 » Mon Jan 06, 2020 2:07 pm

Hi guys. I just got my '14 PPV the day after Christmas and brought it home. Took it on a road trip to Kansas City and when I got back realized the thing has a pretty considerable oil leak. There is oil all over the bottom of the back of the engine and all over the transmission. I felt around the oil pressure sensor to see if it was leaking, it's dry so I'm assuming it's the rear main seal. Any advice for changing it? How easy or difficult is it to drop the transmission in these cars?

s/c'd cav
Posts: 799
Joined: Mon May 30, 2016 8:12 am
Location: PHOENIX AZ

Re: Leaking rear main seal

Post by s/c'd cav » Mon Jan 06, 2020 3:52 pm

its kinda a bitch , the trans is big and heavy

id recommend cleaning the area best you can , top to bottom , front to back , before doing any work to actually fix anything

CrashTestDummy
Posts: 2011
Joined: Sat Feb 07, 2015 8:31 pm
Location: Pearland, Texas

Re: Leaking rear main seal

Post by CrashTestDummy » Mon Jan 06, 2020 3:54 pm

Can't help with the trans drop, but I'll note that the oil cooler mounts off a boss above the oil filter. Our '10 Tahoe had a leak around a plug on the back of the cooler mount. Easy enough to fix, but there was oil staining on the back of the engine, too. Not sure what the Caprice oil cooler configuration looks like, but you might also check around for a similar plug. Here's a picture of the Tahoe part:

Image

The leaking plug is on the lower right side of that aluminum block with the tubing coming out of it in the photo. The oil filter is to the lower left corner, and the transmission is off the lower right corner.
Gene Beaird,
Pearland, Texas
2012 Caprice 9C1
1992 B4C 1LE Camaro
2010 Tahoe PPV (her car)
1995 DGGM Impala SS
1996 BBB Impala SS (11-second DD)
1985 Firebird - 310 LS1 C Prepared autocross car.
And some others
Do YOU have my SPID?

mikem85
Posts: 11
Joined: Wed Jan 01, 2020 5:19 pm

Re: Leaking rear main seal

Post by mikem85 » Thu Jan 09, 2020 7:06 pm

So I got the car to a mechanic, he put some dye in the oil to find the leak and apparently it isn't the RMS, it's coming from up high on the engine and it's about impossible to tell where from. Is there anything closer to the top of the engine that would leak that bad? Again I checked around the oil pressure sensor and it was dry. Would the intake gasket leak oil if it was bad? Maybe even a valve cover gasket? Anything else up there that I can't think of? He said he would have to pull the intake to see where the leak is coming from. Where are the oil cooler and lines on this thing? Any help is appreciated. Thanks!!

Pursuit
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Re: Leaking rear main seal

Post by Pursuit » Thu Jan 09, 2020 7:12 pm

The oil cooler is ahead of and slightly above your oil filter. It is kind of diamond shaped, sandwiched aluminum block. It circulates engine coolant through it, to cool the oil. There are no oil lines leaving it. But, they have been known to possibly fail.

Maurice
Maurice Sheil

mhsheil@gmail.com

2011 Caprice Phantom Black 9C3
2012 Impala 9C1
1995 9C1 Caprice
1996 GMC Sierra C1500
1974 SJ Grand Prix 455 well optioned with factory moon roof

mikem85
Posts: 11
Joined: Wed Jan 01, 2020 5:19 pm

Re: Leaking rear main seal

Post by mikem85 » Thu Jan 09, 2020 7:15 pm

Could a head gasket cause this amount of oil leakage? Speculating with a flashlight it looks dry but I'll check it again after I get the car back.

mikem85
Posts: 11
Joined: Wed Jan 01, 2020 5:19 pm

Re: Leaking rear main seal

Post by mikem85 » Thu Jan 09, 2020 7:33 pm

Also the cam and lifters have likely been replaced on this engine based off the number of hours on it. Could that DOD manifold leak oil under the pressure sensor? Like if whomever did the work jacked up that gasket somehow?

s/c'd cav
Posts: 799
Joined: Mon May 30, 2016 8:12 am
Location: PHOENIX AZ

Re: Leaking rear main seal

Post by s/c'd cav » Thu Jan 09, 2020 9:55 pm

up high is either going to be valve cover gaskets , valley cover , or the oil pressure sensor

mikem85
Posts: 11
Joined: Wed Jan 01, 2020 5:19 pm

Re: Leaking rear main seal

Post by mikem85 » Fri Jan 10, 2020 3:12 pm

I figured it out!! There's a steady leak at the very top middle under the valley cover. Was pretty easy to feel for so I'm gonna ask for my money back for the dye test since the mechanic was (IMO) too lazy to find it. Does anyone here have a good reference for torque settings on the intake and valley cover bolts?

CrashTestDummy
Posts: 2011
Joined: Sat Feb 07, 2015 8:31 pm
Location: Pearland, Texas

Re: Leaking rear main seal

Post by CrashTestDummy » Sat Jan 11, 2020 5:08 pm

mikem85 wrote:
Thu Jan 09, 2020 7:33 pm
Also the cam and lifters have likely been replaced on this engine based off the number of hours on it. Could that DOD manifold leak oil under the pressure sensor? Like if whomever did the work jacked up that gasket somehow?
I see you figured it out, but never assume the lifters fail on high mileage/hours vehicles. Our Caprice got lifters/cam replaced at 23k miles, but our ‘10 Tahoe PPV is still running on OEM parts. Just a comment here.
Gene Beaird,
Pearland, Texas
2012 Caprice 9C1
1992 B4C 1LE Camaro
2010 Tahoe PPV (her car)
1995 DGGM Impala SS
1996 BBB Impala SS (11-second DD)
1985 Firebird - 310 LS1 C Prepared autocross car.
And some others
Do YOU have my SPID?

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