Put off PTU replacement?

[WVMKX]

Hello, all. I have a 2007 MKX AWD. In late December I noticed some thick black fluid in the driveway where I park. I took it to the dealer and I was told that the PTU is leaking fluid. They quoted me around $1600 to replace the PTU. They said that replacing the seals could fix the problem, but they might find that the PTU needs replaced when they open it up. The service manager told me that when they checked the PTU fluid, it seemed to be overfilled.

 

My question is, is there any risk to putting off replacing the PTU? Is there any risk of damage to the transmission if I put off this repair?

 

The reason I ask about the transmission is that I've seen where there can be a seal that leaks between the transmission and the PTU. It made me wonder if the leak goes in both directions, and could contaminate the transmission fluid. Or could it cause the transmission fluid to become low enough to cause damage.

 

Can I put off the repair to the PTU until there are other symptoms than just a few spots in the driveway? Or, could I just add fluid to the PTU periodically? Or should I schedule a replacement soon?

 

If anyone has any advice on what is the best thing to do in this situation, it would be much appreciated.

Edited April 9, 2016 by WVMKX

[Brian K]

Wow - no replies. After reading lots of posts about the crappy, poorly designed PTU, if I was in your situation, I would definitely get underneath the vehicle and add more 75W140 to the PTU. I tried sucking out old fluid and didn't get much out but what I did get was think and gooey. Then I refilled it with oil. The level was way down. Like others, I had black sludge on the fill plug. My service manual says to fill the unit to the bottom of the fill hole and that is what I am doing. Adding oil should extend the life of your PTU although your seals are leaking apparently. However, based on what I have read, it could also be that the fluid (or goo) is getting pushed out the upper vent - a precursor to failure because of loss of even more fluid.

I don't know if there is a common seal between the transmission and the PTU but since it is a separate device, I think they are separated so don't think the PTU fluid will contaminate the transmission fluid.

I am going to install a drain plug in my PTU and drain and fill it a lot until the fluid looks like what I put in. Hopefully, as others have found, new oil will extend the life.

[WWWPerfA_ZN0W]

Thick black fluid is usually pure PTU fluid, so probably not a seal leak. I would R&R the fluid or have a BG flush done first. My preference is BG flush simply because it will get the PTU as clean internally as reasonably possible without opening it up, and will protect the PTU further down the road. Can even take a sample to confirm that fluid looks ok (no metal shavings, a few flakes here/there are normal).

http://bgfindashop.com

Look for the "gear" symbol, which means the shop performs driveline services.

[Brian K]

I'd do the fluid R&R before considering a PTU replacement. Much cheaper and new oil can go a long way to keeping the device happy.