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Rear main seal wet - noted 12K after transmission change

The rear main seal is wet (not dripping on ground) on my '03 Honda Accord - found around 96K miles (after a shop did a detailed check from replacing the power steering pump). The automatic transmission was replaced the year before when the car had 84K miles. (Honda picked up about 2/3 of the cost of the transmission repair.) Should I have been offered to replace the rear main seal of the engine/transmission at the same time?



[The shop that did the work says no - there was no leak. Other shops say, yes, they should have because it had been disturbed. To fix at the time, would be about $200. To fix it now, it will cost $800 since they need to pull the transmission again.]



Other folks say, it is not leaking, don’t worry too much, just watch it. If it starts to leak, then you need to replace it.

I agree with the “other folks”. If it’s not leaking and you don’t see drops of oil regularly on the ground, don’t worry about it.

What I don’t see is how the seal was disturbed,was the flexplate removed? That being said is a mechanic required as in “the mechanic will pay” if he doesn’t offer or bring up the issue that something should be done now as it is way easier to do it now than after the trans in back in or is he just guilty of not thinking ahead far enough for his customer?

If a mechanic habitualy lets his customers down this way the law of the jungle may take over and he looses so much business he loses his business. I don’t think he has any legal obligation but it is just good business to try and think of these type of things.

Anytime the engine or transmission comes out of a vehicle the seals on those units should be replaced. This means engine rear mains seals, automatic transmission torque converter (front pump) seals, and even a mainshaft seal on a manual transmission IF the latter does not entail a transmission teardown.

It’s not only the proper way of doing the repair it also prevents a customer from becoming irate over a leak that occurs shortly afterwards.
There is no way I would ever NOT replace seals if the engine or trans was out.

Something else to consider here. Have the PCV valve checked. If the PCV is faulty the engine crankcase will pressure up and this can cause oil leaks. A rear main seal is one of the main areas that can leak due to a PCV problem.