speedwaywhite

Ran my 12 GS @ PBI Saturday, towards the end of my 3rd session the trans began up shifting (early) on its own. No issues down shifting. I suspect this was because trans temp may have been over the max operating range and this was the ECU helping to lower the temp. Anyone have any experience with this?

Any recommendations for High Temp ATF?

This was my first outing with Performance Driving Group, good crew, stayed on schedule, well run event.

Thanks in advance for comments/suggestions

VETTERACER11

Not sure about the upshifting, probably trans temp related.

Auto trans fluid, I always had great luck with Mobil 1 Full Synthetic ATF fluid.

For Manual trans, Redline D4 ATF Full Synthetic works great.

My experience using Redline D4 ATF in an Auto trans is that the trans shifted too firmly ( even under light acceleration ) for my liking.

el es tu

Thats odd; I have never experienced that with high trans fluid temps. Where were they when this started occurring?

btw if you want to keep the A6 happy you could look into an external cooler...

Bluefire

I was running my A4 on the track this year (~6x). Generally, at the end of my third session, the trans fluid temp was high (~265F). The PCM won't allow any gear shifts then. D4 (OD) only. I have an aftermarket cooler (Setrab 25-plate).

I got tired of adding Band-Aids to keep it cool. So, I made the big choice to swap out the A4 for an MN12.

Consider wrapping your exhaust pipes where they run underneath your transmission. That will cut down on the "heat soak" in between track sessions.

speedwaywhite

Thanks for the replies, up shifts began late in third session, shifts were occurring around 4000 RPM. Previously I was shifting at 5500/6000 range. I was going to second gear in turns 1,4,6 and 10. A buddy of mine was there with same car and staying in third and had no issues which may or may not be related.
I like the idea of a cooler but, not sure where to mount it, stock radiator may not be up to the task. Exhaust wrap is a good idea, should help, I will get some before returning next month.
Will try and upgrade ATF.

el es tu

the factory trans lines run to the radiator as its supposed to act as a "cooler" (however it does help warm up the fluid faster in cold weather); you can either bypass the radiator one, or connect into the exit line from the radiator.

people typically mount the cooler against the front of the radiator

im currently looking into using two small coolers on the back of the car just to keep weight off the front...

Bluefire

I chose to bypass the radiator. Some folks on here thrashed me for it saying the "hot fluid bath" actually cools the trans fluid better than the bypass method.

jbondfl

I'll be getting a DeWitts in a few weeks just to prevent this. Getting down into 2 a lot will definitely warm things up (probably not because it is 2nd, but because you are shifting more often).

And make sure your replace your trans fluid with a really good full synthetic. I'll be going with Redline.

blkbrd69

This is what it took to keep mine cool.

http://forums.corvetteforum.com/auto...-course-t.html

If doing track days in Florida you "will" need engine trans and brake cooling.

ErnieN85

The new a6requires d6 atf

nolimits

You're right its due to temp. When trans temp exceeds ECU tune parameter it kicks in to a safety mode. Like others have said get a good external cooler or radiator combo and you'll be fine. I had this issue with my 06 A6 when pushing hard, highly modded, hoosiers etc on warmer days.

speedwaywhite

I have no mods except brake pads (Hawk HP plus frt & OE GS rear),brake fluid (Stop Tech 600).
Tires:Eagle F1 G2 ROF all around.
I will be changing trans & diff fluids soon. The A6 appears to be a pain to service, will hire a pro with the right equipment.

Unsure of what brand of synthetic fluids to use, lots of choices.
Mobil 1, Red Line, Royal Purple, Wolfs Head, Amsoil. Did I leave any out?

el es tu

iirc castrol is the oem stuff

blkbrd69

I used OEM D6 from the dealer in gallon jugs, was able to convince them to give it to me at wholesale. If I did it again would probobly use Redline, get the online price match and free shiping from Jegs.

Drain by dropping pan and pump back in using normal autoparts store fluid pump, not that hard.

speedwaywhite

In my quest to lower trans temps while running HPDE I have been shopping for heat shield covers for trans lines. I am finding some nifty products available, some wrap others slide over the line. Anyone out there used any of these products?

nolimits

Remember lines can dissipate heat too if in relatively open air and have gaps from anything around them, avoid any lines contacting hot surfaces obviously.

Bluefire

While you're wrapping stuff, consider wrapping the exhaust pipes where they run underneath your transmission.

speedwaywhite

I plan to cover the lines where they run through the tunnel. I wonder what would be more effective, wrap exhaust in the tunnel or shield the lines?

Gering

Thanks for the link.