'01-S8

What is the operating temperature of the transmission supposed to be? What is the max temp it should get to?

What screen can i monitor in VAGCOM to keep an eye on trans temp.

'01-S8

Seems I can monitor under Group 4, under measuring blocks.

Is the trans cooler in the radiator? Prob a hard line running into another port on the radiator like most automatics??

Could I bypass it with an external cooler?

Razman

Run a line from the 'exit' port of the existing tranny cooler to an external one. You'll still get the benefit of the radiator cooling with the external one in addition to it. This is what I did on my Subaru when we needed to tow a trailer a long distance.

As for whether the D2 has a tranny cooler in the radiator, I can't say.

Raz

'01-S8

Where is the existing trans cooler?

Where is the "exit" port located ?

Thanks

dreamhope

http://www.jimellisaudiparts.com/sho...category=21740

'01-S8

So from this picture it looks like the trans has its own cooler??

Do we know what the temperature range is for the trans?

gorfllub

I don't know the answer to your question, however:

Can you actually read the temp through the vag-com?

If you are not suspecting any problems, drive it around for an hour and see what you get. Then try and drive it hard and see where the temp goes from there.

Then you have a rough idea of a baseline.


I too am curious about this since the transmissions seem troublesome. I think I will install some sort of gauge I can monitor all the time for safety and possibly an additional cooler "just because". I do not want to put a tranny into one of these if I can help it.

Or depending on how the factory cooler is mounted, possibly a fan for it for additional airflow.

'01-S8

Yes you can monitor it through VAGCOM.

Mine was at 40 when I started, got to 46 while i let it warm up for about 5 minutes, then to 60 after about 10 minutes of driving. Did a bunch of stop and go and harder driving and got to a little over 70 overall. After about 20 minutes of various driving it was hovering at the 73-75.

75 would be 167 Fahrenheit, and I dont think thats an issue temperature. Thats prob right about where it should be.

My thought was that maybe the cooler isnt performing properly and was causing the trans to get too hot causing symptoms. I thought this because when my car first moves and for about the first 10 minutes, the trans is perfect. No problems. ZERO hesitation, and is flawless. Mash it all you want. Even if I let it warm up for 20 minutes before driving. After its been going for a little bit, if i press hard from a stop I get a thump from time to time. But the temp doesnt seem to be the issue.

dreamhope

Thumping after warmup is possibly a hydraulic issue.

twentysevenlitres

The transmission cooler is located within the left hand tank of the main radiator.
It is cooled by the radiator coolant - you cant get a fan to it

The top hose is the feed. The bottom hose is the return.
Both fittings are sealed by o-rings 11.5mm x 3mm (part no. N90666001), consider replacing them if you remove the fittings.

The picture dreamhope linked to shows the main radiator.

If you intend to tow, a transmission cooler is a good idea.
If you're not going to tow, a transmission cooler won't hurt, but I don't think cooling is necessarily the problem with these transmissions.

If you do mount one, ensure you plumb it into the return hose as razman said.
Use good quality fittings and choose your location carefully as you can't afford leaks with no dipstick on these transmissions, and the timing belt job requires removal of much of the front of the car...