audiglenn

I took my car for a trip to Arizona the past week. Temperatures were in the high 20's, low 30's. When I returned, I noticed some fluid underneath the vehicle which I think is transmission fluid. The temperature here is in the low to mid 50's. The leak occurs just forward of the cross bar between the 2 under belly covers under the transmission. There is also 2 small metal tubes running across. I attempted to tighten the bolts on the transmission around the leak. They are already very tight. The slow leak doesn't seem to happen while the car is idling. After a long drive, I also don't observe any leak/wetness. However, I observe a leak/wetness between the 2 under belly covers and small oil puddles underneath the following morning.

I am not observing any driving issues with the transmission but I do notice slipping under heavy acceleration going up a steep hill. I have not got any warnings of low transmission fluid. Will the ECU warn me when the fluid is low?

Not sure what the CVT fluid looks like. The liquid under the vehicle is clear and slippery and sort of pinkish.

Would appreciate guide any guidance/suggestions.[CENTER[/CENTER]

chapstick

The particular angle that the underpanels mount make it easy to misdiagnose where any fluid leak(s) are from. you'll see several holes in the plastic towards the transmission that serve as drainage. So something from the front may actually be collecting towards the rear of the panels.

It's highly unlikely that the your CVT fluid is the source. That particular transmission is an especially closed system. The two drain plugs again are definitely not going to be leaking. Unless there is major damage to the transmission housing you can probably scratch that off. Audi factory filled CVT fluid is a gold amber color just like fresh motor oil. It has a peculiar smell that reminds me of a brand new vinyl beach ball of all things. Curious what you meant by "slippage at high speeds" though.

There are leak points at the differentials of the cvt transmission, but that fluid leak USUALLY doesn't produce a dripping leak. It is more of a very slow saturating leak if you will. Just like how water travels on a tissue; differential fluid "spreads" over the naturally occurring oxidation on your drive axles ends and gives them an always wet appearance.

What is a dead giveaway is that you mentioned that it was PINK. Any pink fluid that is enough to cause drippage is most likely Audi specified coolant. There is a coolant flange at the firewall side of your block that usually leaks at its base between the itself and the block. Leaks at your coolant temp sensor that is housed by the flange can also be leaking at its gasket.

At first coolant leaks at the flange are barely enough to bring the level down in your the expansion tank to a noticeable amount. Leave it unfixed then that can change in varying time frames between each car.

What bothers me is that you said it was particularly "slippery". Unless it was just a mixture of road grime, previous oil changes and moisture run-off, I would say that it could be a combination of things. There's more than several likely culprits that could be causing this mix of coolant and oil to collect on the panel. Don't worry, I don't think its a head gasket leak - you'd know for sure if it was, but you or someone good with auto repair should remove the panels and take a close look at all the leak points; everything from steering to oil filter housing.

Good luck.

audiglenn

I removed the front under belly cover because I thought it would help me find the leak. I will clean up the under belly cover and put it back on to see where the leak and attempt to trace the leak based on the oil on the underbelly cover. The fluid under the vehicle doesn't smell like motor oil. It smells sweet and is slightly pink. I will continue to observe my coolant reservoir. Is audi coolant different than other coolants?

Kris Hansen

Yeah, that's coolant.. It will feel slippery especially once the water evaporates from it..