01M transmission coolers

I know its a big thing about the transmission and heat..or overheating. The stock transmission cooler is mounted on top of the tranny? really.. that seems logical..

What are good ones?

http://www.jcwhitney.com/p2000991/sku-179307.jcwx?filterid=c3758d14322y2002g62u0j1


also found this one"

http://www.jcwhitney.com/mr-gasket-...3092231.jcwx?filterid=c3758d14322y2002g62u0j1

seems like a fmic for the tranny is best .. but whats that tube one, never seen one like that.


I see this is a front mount in front of the radiator..... any other ones people would suggest?

I can't comment on the aftermarket coolers, but the reason the stock cooler is mounted where it is, is because it uses engine coolant, rather than air, to cool the transmission fluid. I've seen pictures of setups that use both the stock and aftermarket coolers in series. I've never set something like that up, though.

And from what I've read of those that monitor tranny temp, it follows the engine coolant temp fairly closely, so the OEM cooler/exchanger does a good job of heat transfer in typical use as normal coolant temps aren't too high for the tranny fluid.
I think the issues with the 01M are seperate from fluid temps being what they are.

lovemybug said:

I can't comment on the aftermarket coolers, but the reason the stock cooler is mounted where it is, is because it uses engine coolant, rather than air, to cool the transmission fluid. I've seen pictures of setups that use both the stock and aftermarket coolers in series. I've never set something like that up, though.

Click to expand...

I cant comment on the stock cooler, but I've been told by a transmission engineer that putting an extra cooler in series can have a negative effect. Extra length of travel can cause both flow and pressure drop. He said your better off with one bigger cooler than two in series...

Solution in search of a problem. If your ATF got "too hot", you'd know it, because the ATF temp sensor would send that signal to the transmission controller, and it would first attempt to modify shift strategies and lockup to curb the problem, and if that wasn't enough, it would have a talk with its good buddy the engine controller that sits right next door, and it would limit engine output accordingly. You'd also have a DTC stored in the TCM, and if it happened enough, it would tell the ECU to tell the Instruments to turn on the MIL.

Since I am 100% certain you have NONE of those things happening, your ATF temp is perfectly fine, and you have nothing to worry about.

The 01M is certainly no gem of a transmission, but the temp of the ATF has absolutely nothing to do with that. If it were, I would have blown up the 098 in my T4, which is the "truck" version of the 096 which is the early version of the 01M. Since I have drug other cars around with it, some weighing nearly as much again as it does, and haven't overheated the ATF, I'd say your little Golf or Jetta is perfectly fine.

Never thought of that, but it makes sense, adding extra run to the fluid lines would not be optimal.

I have to disagree here, even though this is a bit of a zombie thread. I monitored transmission temps reaching 250 degrees in heavy traffic from my scangauge - I thought the computer must have been getting garbage readings so I pulled over and hit it with my IR temp gun - 245 in the pan. So the sensor was reading accurately, and there was NO CODE SET or any other engine-related changes.

Were there changes in the transmission? Yes - the computer put it into "safe mode" where it decided to NOT LOCK THE CONVERTER AT ALL... And that was when the temperature really started to climb from all the slipping! Turbulent fluid makes heat, and the converter is very very good at that. The factory transmission heater unit though is very BAD at removing heat from the transmission.

Ok, so this is my first post on here, but here is where my head is. I also have 01M in my 2003 golf. My tranny works perfectly when it's cold and been sitting. Under freeway driving, it's also perfect. only under stop n go does it start to shift at high rpm's and slip in 4th gear. I'm also thinking heat related. Couldn't you just remove the engine thermostat and let everything run cooler. I understand the engine runs better warm, but why not give it a shot. .... any ideas?

Valve body is probably leaking fluid and when it thins out the fluid leaks faster and looses pressure.

Removing the engine thermostat is a terrible idea.

No, in all likelihood what you are describing is the transmission running hot because the torque converter is an amazing generator of heat when not locked up... So the computer detects this heat and puts it into "safe mode" where it will not command lockup even if the speed allows it... And thus, generates EVEN MORE HEAT!

Such a great design of programming!

Sonnax makes adapter banjo fittings that you use to install an external cooler instead of that useless factory mess. Put the cooler in the front of the radiator stack, so that one of the fans (or both) can pull the air through when the AC is running. That will keep the transmission cool when there isn't enough airflow to keep it cool.

I hope you have changed the fluid by now, and possibly several times based on mileage! Change the fluid about every 40k and the transmission will be much happier.

What is worse that a "rolleyes" smiley?

Anyone know the thread size for the bolts on the stock cooler?