Had my 2020 RDX AWD in to the dealer for the 100,000 mile maintenance. They said I need a new transmission because of fluid between the transmission and the transfer case. Stated that the gasket between the 2 could not be repaired. Is this correct? The cost is quite high.

 

I don't know whether it can be separately repaired, but I have had very slight ooze of that type ever since I first looked there. I wipe it off at each oil change, and a small amount is there again at the next one. I would say that the amount in your photo is about the amount I accumulate in 12-16k miles. I have heard that dealers say that it is some sort of grease, and it not a problem (at least, they say that while you are under warranty). If it were mine, I would clean it off with rags/brake cleaner, verity that the transmission fluid level is correct, and check it again in a couple of thousand miles. I see that you returned 1k miles after they added UV tracer to the transmission fluid -- was all of the previous leak cleaned off at the time that they added the UV tracer?

At that cost, I personally would just monitor it and top up the fluid as needed until that becomes ridiculous. However, I do my own maintenance of this type (fluids).

 

Thanks. To be clear, the first 'cleaner' photo was after servicing an about ~1,000 miles. The other photo with more residue was when we first had taken it in. The area was wiped and UV tracer added to the transmission fluid. It looks like a slight amount of the tracer is showing after 1,000 miles.

 

Does fluid accumulate on your cover plate? Its definitely a leak, but if its a slow one, you might be able to continue driving and just top off fluid every 10-15k miles. However, its not so simple to top off a fluid by DIY, so you might have to have someone do it for you.

I also have a slight seep from my transmission case, not as bad as yours and not enough to drip on a cover plate.

Here is how mine looks like https://acurazine.com/forums/3g-rdx-.../#post16842870

But it takes 5-10K miles before it looks like that, and plate is dry. This was since it was new, and dealership refused to do anything. I am now at 55K miles, seems to be OK. I change fluid every 30k, there does not seem to be a noticeable fluid loss.

 

Hmm - something I need to look at next time I'm under there changing my oil.

I'm with the others here - if it's not enough to accumulate or otherwise make a noticeable impact on your actual fluid level, it may be something to just keep a close eye on to see if it changes over time, especially if the transmission is otherwise working fine. If you're eventually facing the cost of replacing it, you may as well extract as much life out of it as you can.

 

That seems ridiculously expensive for a transmission replacement, like 2-3x what I was expecting, on par with engine replacement prices. Have you tried going to a reputable independent mechanic?

For a 2020, assuming you don't have extended warranty? I think they can go up to 120k these days.