Drano38

Help!
2010 GT, auto transmission. SCT race tune installed, GT/CS valance w/ Steeda brake cooling kit.
Can an auto transmission vent fluid? Or the power steering system?
I was at Mid America Motorplex this weekend for a 2 day driving course.
Overdrive off, and in Sport Mode, so both lights illuminated on dash.
Manually shifting between 3rd to Drive, and routinely hitting 5,500 RPM, and sometimes 6,500 as the race tune called for a late shift at full throttle on the long straight.
Sunday I was getting better and pushing the car pretty hard. During the last lap of a 20 minute session (3rd session of the day, but after lunch break), the Overdrive light went out, and wrench on the dash illuminated ("limp mode" per the manual). Also, when I got to the paddock, drivers behind me said just prior to every corner during the last lap, a cloud of smoke came out from behind the car (probably during heavy breaking).
I jacked the front up a bit, and the frame was wet beside the engine and K-frame on driver side, and then trailed back to the rear bumper. Front drivers wheel also had some fluid on the inside of the rim. Smoke was obviously burning fluid on the exhaust system. A couple drops on the K-frame attachment were red, so ATF from either power steering or auto transmission. I couldn't pinpoint where the fluid originated from.
Power steering fluid is now just above the "Min" line. I think it was higher last week.
But with transmission switching back to Overdrive mode (Overdrive Off dash light off)--I'm pretty sure I didn't hit the button--and the wrench illuminating for limp mode, I'm thinking its more a transmission thing than steering. I didn't see the wrench until almost the end of the cool down lap, and it drove off the track fine.
One guy I talked to said the transmission fluid may have gotten so hot it frothed and then vented (if there's a vent on a '10 auto). He looked at the steering rack and that didn't seem to be it (but hard to see under the plastic moldings.) He was confident I could drive home, so I did (3.5 hours). Drove fine, and of course smelled like some hot burning fluid when I got out of the car, but I expected that.
Any ideas?
It will stay in the garage until I talk to the dealer. I'm under warranty, so good there. Of course, they may wine about being on the track, but hey, the BOSS was made for the track and I'm guessing they have a warranty.
Sorry for the long post. Thanks for the advice.

tx_zstang

Look on the top of your transmission: there's a hose that runs from near the back of the transmission case to the top of the bellhousing. That hose is a vent hose, and under harsh conditions, such as you described, the fluid will 'vent out' through that hose, and empty into the bellhousing, and drain down and out the bottom, getting everywhere. Nice, huh.

To prevent that, you can put a catch can/breather in the engine compartment, and run a hose up to it instead of the bellhousing, preventing fluid from leaking out.
You want to catch any fluid and prevent it leaking out like it did.

I'm using one I made out of PVC pipe caps, various fittings I had laying around, and a cheapy little filter. Not a drop lost anywhere in the bellhousing anymore.

808muscle

Yeah you need a trans catch can. You can make one or buy one from JDM. If you climb under the car and reach up to the top of the rear part of the trans you can feel that hose. It runs forward towards the bellhousing and vents the fluid in there. You could be low on fluid now too. Having a catch can there gets the hot fluid out of the tranny but then allows it to flow back into it after it cools. Therefore no loss of fluid. If you need help installing one, just pm me, its not difficult after you figure where it ties in.
I mounted mine on my cai shield.

Drano38

Dealer said last week it was transmission fluid, which I expected.
Today I had them replace the fluid (yea, at 5,000 miles). A well respected local maintenance shop said if it vented it may have gotten hot, so best to error w/ caution and change it.
Dealer said it was over-filled from the factory, which is the main reason it vented. Even after it vented, and coated quite a bit of the car's underside, it was still over-filled.
But I'll install an Aeroforce Interceptor gauge and see what my fluid temp is.
Still undecided on a catch can. Wish it didn't cost so much, and I don't think I want to mess with the install. I looked behind the motor, and didn't see anything that looked like a vent hose. But I'm not a weekend car mechanic either.
Thanks for the help.