Rear main seal leak?

[Mrsteef]

Had my muffler welded in the other day and my buddy had pointed out an oil drip. It’s was on the bottom of the oil pan and the transmission inspection cover I’m guessing? He said it looked to him to be the rear main that was leaking it’s way down. So I called up another good friend of mine and got a quote to replace it.

He quoted me around $575 with a timken rear main seal.

Sound like a deal? Or what would the normal cost be. I’m not going to try and do it myself, not because I’m not confident enough to do it but because I really don’t feel like pulling the trans in the driveway.

 

[kbuskill]

Had my muffler welded in the other day and my buddy had pointed out an oil drip. It’s was on the bottom of the oil pan and the transmission inspection cover I’m guessing? He said it looked to him to be the rear main that was leaking it’s way down. So I called up another good friend of mine and got a quote to replace it.

He quoted me around $575 with a timken rear main seal.

Sound like a deal? Or what would the normal cost be. I’m not going to try and do it myself, not because I’m not confident enough to do it but because I really don’t feel like pulling the trans in the driveway.

I would pull the inspection plug on the bell housing and make 100% sure it's the rear main leaking.

These trucks have either oil cooler lines or a block off plate installed directly above the oil filter on the side of the block. They are known to leak and can easily blow back and drip from the oil filter or the bottom of the pan and bell housing. Could also be the oil filter itself leaking a bit.

 

[nadthomas]

I second kbuskill. Pop out the inspection cover and shine a flash light up there. When I first got my Denali I thought I was dealing with a similar situation. Turns out I had slow leaks from everywhere but the rear main.

 

[drakon543]

i was quoted somewhere around that to do the rear main on my 97. totally different engine and such but same concept. the place i had align the truck was a bigger garage and shot me a price that i could have just bought an engine from rock auto. had mine done for alot less but im just lucky to have connections. second note regarding the suggestion to double check is a definite. my rear main was leaking so it was replaced but the bigger issue was my oil pan gasket was leaking badly right next to the rear main.

 

[Mrsteef]

Got under the truck and pulled both inspection covers and luckily I didnt find any oil inside the bellhousing. But that block off plate was a little wet with oil, but also on the starter side it was a bit oily



Ordered the gasket for the block off plate and also ordered a new oil pan drain bolt just to rule it out.

 

[inmypassatlife]

Comes with a nice o-ring gasket,
https://www.amazon.com/ADAPTER-Cool...pID=419BKeED4IL&preST=_SX300_QL70_&dpSrc=srch

I'd also look at doing the oil pan gasket, its a 2 hour max job if you are 2WD. 4WD I have no clue but I'd expect double that. I would also check the Cam position sensor at the top of the intake. Most common for that drip from the top, most folks will say its the oil pressure sensor but that is the #1 replaced sensor up top and most times doesn't fix the issue.

 

[Mrsteef]

Comes with a nice o-ring gasket,
https://www.amazon.com/ADAPTER-Cool...pID=419BKeED4IL&preST=_SX300_QL70_&dpSrc=srch

I'd also look at doing the oil pan gasket, its a 2 hour max job if you are 2WD. 4WD I have no clue but I'd expect double that. I would also check the Cam position sensor at the top of the intake. Most common for that drip from the top, most folks will say its the oil pressure sensor but that is the #1 replaced sensor up top and most times doesn't fix the issue.

Damn wish I saw this before I ordered the gasket. I’ll probably order this anyway just in case. I looked at the pan gasket and that seems to be pretty dry, I’m leaning more towards something else. I’ve wiped it all clean so hopefully if/when it starts leaking again I can spot where it’s coming from

 

[kbuskill]

Damn wish I saw this before I ordered the gasket. I’ll probably order this anyway just in case. I looked at the pan gasket and that seems to be pretty dry, I’m leaning more towards something else. I’ve wiped it all clean so hopefully if/when it starts leaking again I can spot where it’s coming from

How are your valve covers???

 

[Mrsteef]

How are your valve covers???

They seem fine from what I can see

 

[inmypassatlife]

Damn wish I saw this before I ordered the gasket. I’ll probably order this anyway just in case. I looked at the pan gasket and that seems to be pretty dry, I’m leaning more towards something else. I’ve wiped it all clean so hopefully if/when it starts leaking again I can spot where it’s coming from

order this one anyways, best bet. I actually threw mine in there with both gaskets and some black RTV. better to be safe than sorry.

 

[Mrsteef]

Starting to lean toward the pan leaking, just came back from lunch and checked underneath and it’s coming from up higher I’m thinking

 

[NardDog]

Starting from the top down is cheaper, however in my experience all chevy truck motors will need a rear main at some point. I would think the price would include the pan gasket, seems like a reasonable price. See if you can haggle hom down

 

[Mrsteef]

I’m going to pull the starter when I get home and check the crank position sensor just to be sure and also get a better look at that side of the pan. I already checked the oil pressure sensor on the top, it was bone dry and looked somewhat new

 

[Mrsteef]

Figures it out.. it’s leaking on towards the rear both sides of the oil pan. Also at the block off plate. Removed the starter to check the crank position sensor but it’s dry. Degreased everything, dried and watched it slowly pool up here

 

[Bill Hayes]

These trucks or should I say these engines, have the PCV valve in the DR side valve cover. I would check that first. Pull off the oil filler cap on the passenger side and it should be sucking while the engine is running. Check with a paper towel. If it is choo chooing like a train, the PCV valve is stopped up. Hook a hose to the valve cover and see if you can suck or blow on it. It should have a small amount of restriction. Mine was stopped up tight and was leaking at rear main and pan gasket. I changed the DR side valve cover and it stopped leaking.

 

[Mrsteef]

Did the oil pan gasket today along with a new drain bolt and also the gasket for the block of plate and new oil pickup o ring. No leaks as of yet

 

[Mrsteef]

Only hiccup was one of the long rear bolts snapped because the directions I was following for torque specs didn’t say the long bolts were a different torque... seems to be holding up though. I’ll eventually pull it again and change it out. Pan to block bolts are 18ft/lbs and the two long bolts towards the bell housing are supposed to be toruqued to 106in/lbs. Wish I knew that.