Replace crank seal or not?

[wingnut1961]

Opinions wanted. 98 M3 with 88K miles. Transmission is out, rear main crank seal is dry. Replace it now or wait?

[EricP]

Is that referred to as the 'rear main seal'? If so I've heard it's definitely something you wanna do while the tranny or clutch is out, so long as you do it right and don't CAUSE a leak :)

[Ron97M3]

Opinions wanted. 98 M3 with 88K miles. Transmission is out, rear main crank seal is dry. Replace it now or wait?

I say leave it alone. Haven't heard of too many will rear main seal leaks and there is a risk of messing with it and causing the leak. If you had double the mileage I would say go for it!

[BMuu]

I would do the tranny input shaft seal too if you plan to replace the rear main seal. My tranny input shaft seal went out at 120k.

[Ron97M3]

I would do the tranny input shaft seal too if you plan to replace the rear main seal. My tranny input shaft seal went out at 120k.

Was that on a manual transmision? What year was the car?
101projects book talks of doing this when doing the clutch, you are the first
posting I have read about a failure.

[BMuu]

Was that on a manual transmision? What year was the car?
101projects book talks of doing this when doing the clutch, you are the first
posting I have read about a failure.

Manual ZF tranny, 1995 M3

[Jammer1]

Opinions wanted. 98 M3 with 88K miles. Transmission is out, rear main crank seal is dry. Replace it now or wait?
DO IT!!! Especially with the tranny out. My 98M3 with 57k now, has had the rear main crank seal replaced twice! The original owner had it replaced under warranty at 15,442 miles. I purchased the car with 25k. At 41,116 it had to be replace again. The part was $41.75 and labor was $774.20! This was done at the dealer. I would consider it preventative maintenance.

[Ron97M3]

DO IT!!! Especially with the tranny out. My 98M3 with 57k now, has had the rear main crank seal replaced twice! The original owner had it replaced under warranty at 15,442 miles. I purchased the car with 25k. At 41,116 it had to be replace again. The part was $41.75 and labor was $774.20! This was done at the dealer. I would consider it preventative maintenance.

OUCH! Wonder what it is about your car that causes leaking rear main seals, must be something not quite right in that area!

[Jammer1]

OUCH! Wonder what it is about your car that causes leaking rear main seals, must be something not quite right in that area!
I don't understand it either! Original owner is an adult, as am I. Car wasn't abused or anything. The build date is 11-97. When I first heard it, I took it to both BMW dealers here in Milwaukee and neither could diagnose the problem! An indy came closest, saying it was from the back of the engine. I e-mailed BMW about the problem, but just got a bs, how car is maintained,etc reply! I was really pissed! The OO included an extended warranty with the car which had to be used at the dealer. I insisted that the dealer check it. They said OK, but if it wasn't the seal, I would be liable for the inspection cost. I said go for it! During my research of many forums, I found a post about it, which was from 1999! I am hoping it doesn't happen again!

P.S. Love the green!

[Jrdeamicis]

OUCH! Wonder what it is about your car that causes leaking rear main seals, must be something not quite right in that area!

Im sorry but that was just to funny. Its got the clerp.

[E36M34life]

Crazy, $734 bucks just to replace a seal, just crazy! I think for that much, I would have tried and tackled it myself.

[Ron97M3]

What labor is required to replace the rear main seal on a M3?

Is it pull the oil pan pull a bearing cap and use a rear main seal tool to place a new one? What is the big labor item in this job? Does something make the pan
take time to pull or what?

$736 sounds like 4 hours of labor.

[Ron97M3]

I don't understand it either! Original owner is an adult, as am I. Car wasn't abused or anything. The build date is 11-97. When I first heard it, I took it to both BMW dealers here in Milwaukee and neither could diagnose the problem! An indy came closest, saying it was from the back of the engine. I e-mailed BMW about the problem, but just got a bs, how car is maintained,etc reply! I was really pissed! The OO included an extended warranty with the car which had to be used at the dealer. I insisted that the dealer check it. They said OK, but if it wasn't the seal, I would be liable for the inspection cost. I said go for it! During my research of many forums, I found a post about it, which was from 1999! I am hoping it doesn't happen again!
P.S. Love the green!

No kidding! My thinking is there must be something wrong to cause the seal to fail VERY early! Like a rough spot on the main journal of the crankshaft?
Sorry but myrphys law says it will happen again till you find and fix the unlying cause. Double sorry about the BS from BMW, too bad they apparently
don't care about owner satisfaction!

[wingnut1961]

What labor is required to replace the rear main seal on a M3?

Is it pull the oil pan pull a bearing cap and use a rear main seal tool to place a new one? What is the big labor item in this job? Does something make the pan
take time to pull or what?

$736 sounds like 4 hours of labor.

You don't pull off the oil pan. You do have to pull off the exhaust, the heat shield, the drive shaft, the transmission, the clutch and the flywheel. After that, it's a piece of cake (unless you screw it up and it leaks).

[Ron97M3]

You don't pull off the oil pan. You do have to pull off the exhaust, the heat shield, the drive shaft, the transmission, the clutch and the flywheel. After that, it's a piece of cake (unless you screw it up and it leaks).

Bottomline you need to pull the transmission, clutch, and flywheel.
So this means to me that access in the rear main seal is behind the flywheel.
I wonder how come he only paid $736 dollars as removing all that stuff would
take a lot more than a day for sure.

[BMuu]

Bottomline you need to pull the transmission, clutch, and flywheel.
So this means to me that access in the rear main seal is behind the flywheel.
I wonder how come he only paid $736 dollars as removing all that stuff would
take a lot more than a day for sure.

I can do a clutch in 4 hours and thats removing the same amount of stuff and I don't have a lift or anything. Thats about the price I would expect from the dealer, It should be about the same as labor for a clutch job as you have to remove the same things.

[bjl4776]

Warranty time is 7.5 hours to do a rear main seal. I think they give you a little less than an hour over the time it takes to do a clutch. the thing is that most dealers charge more for customer pay, upto to twice as much more. So i wouldnt be surprised to see dealers get upto 14 hours to replace a rear main. For a dealer not to notice a leaking rear main seal that was customer pay and requested by the customer is pretty crazy. Its not that difficult to diagnose a rear main. The leak comes from the trans belhousing. If it leaking from the bellhousing it is either trans input shaft seal, rear main seal, or oil pan. The only other thing to leak above that to leak oil is valvecover gasket and they leak on the exhaust or down the drivers side. Vary rarely a headgasket may leak and cause a mystery, but they normally dont fail that way unless its catastrophic.