[J. Dub]

My rear main seal (where the engine meets the trans) was showing signs of leaking along with the stock inlets from air intake to the turbos.

Both are getting replaced under CPO on my car. But my question is this:

How do I prevent my rear main seal from ever leaking again?

[David0ff]

you cant, its the natural cycle of things

just be thankful it is replaced under warranty otherwise you would be spending 1k-1.5k to replace a 20$ piece of rubber

[J. Dub]

Originally Posted by David0ff

you cant, its the natural cycle of things

just be thankful it is replaced under warranty otherwise you would be spending 1k-1.5k to replace a 20$ piece of rubber

Jesus

[robthewrench]

You really can't do anything preventative. A rear main seal should last over 100K miles. There are at least two things that can result in it dying early:

1) Bad initial install. Nicking the seal, not getting it seated completely, etc... will result in an early failure. You didn't say how many miles on your 2010, but this would be my best guess.

2) Lots of high heat cycles, typical of track racing. That seal is made of rubber and rubber does not like a lot of high heat cycles. The 335 isn't a cool running engine with those turbos (hence the need for an oil cooler). So the rear main seal on the N54 / N55 engine is probably more likely to fail than a non-turbo engine.

But not a whole lot that you can do....

[J. Dub]

Originally Posted by robthewrench

You really can't do anything preventative. A rear main seal should last over 100K miles. There are at least two things that can result in it dying early:

1) Bad initial install. Nicking the seal, not getting it seated completely, etc... will result in an early failure. You didn't say how many miles on your 2010, but this would be my best guess.

2) Lots of high heat cycles, typical of track racing. That seal is made of rubber and rubber does not like a lot of high heat cycles. The 335 isn't a cool running engine with those turbos (hence the need for an oil cooler). So the rear main seal on the N54 / N55 engine is probably more likely to fail than a non-turbo engine.

But not a whole lot that you can do....

74k on chassis. 2k on motor as it's new.
I was hoping aftermarket had a better gasket but I guess not

[robthewrench]

Originally Posted by J. Dub

74k on chassis. 2k on motor as it's new.
I was hoping aftermarket had a better gasket but I guess not

2k miles on the motor and the seal went?

They damaged it either when building the motor, or when mating the motor to the transmission during the installation.

[J. Dub]

Originally Posted by robthewrench

2k miles on the motor and the seal went?

They damaged it either when building the motor, or when mating the motor to the transmission during the installation.

I agree. This is why they're doing all this under warranty.