Fresh trans rebuild with new converter keeps pushing fluid into the overflow tank. Started with fluid level at the "add" mark on the stick. Made 5 runs and drained 13 ounces from the overflow. Didn't add any fluid, made 6 runs and drained 8. Didn't add any, made 4 more runs and drained about 8 more ounces. It has a deep pan, trans temps on the last 4 runs was 147-163 leaving the line and I'm using FTI fluid. Same cooler, same case but added an Ultra Bell & trans brake. 14 of the 15 runs were footbraking. Should I just let it push fluid out until it finds a level it likes? I doubt that the level now will show up on the stick.
Posts: 466 | Location: Maryland | Registered: January 23, 2007
Originally posted by DON KALINA: I KNOW THIS SOUNDS CRAZY..BUT...UNSCREW THE LITTLE VENT & JUST LEAVE AN OPEN HOLE...TRANS. CAN'T VENT AIR ENOUGH OR AT ALL....I'VE SEEN THIS
SEVERAL TIMES...HAD A CUSTOMER WITH A GLIDE...ABOUT 50 RUNS...GLIDE CLEAN & DRY..ADDED AN OVERFLOW TANK, BECAUSE OF TRACK RULES..NEXT PASS
HAD FLUID EVERYWHERE...TOOK US A MOMENT & GAUGE TESTING THAT THE TRANS WAS WORKING PERFECT...TOOK OUT THAT LITTLE VENT..CLEANED EVERYTHING &
MADE ANOTHER RUN....DRY AS A BONE....GOOD LUCK....
Thanks for the reply Don. Are you saying the vent in the tank or the vent on top of the case? I was getting ATF all over the bottom of the car when I started using this case in 2017. Since the freshen up earlier this year it seems worse.
Posts: 466 | Location: Maryland | Registered: January 23, 2007
Originally posted by DON KALINA: I'M NOT A TURBO 400 EXPERT AT ALL...GLIDES ARE ALL I BUILD....I ALWAYS TOOK THE TANK VENT OUT...WORKED EVERYTIME...I LIKE THE REID
TAILHOUSINGS..THEY HAVE A VENT ON TOP..I THINK THEY FIGURED SOMETHING OUT A FEW YEARS AGO...I'M A BTE DEALER & THEIR TAILS DON'T HAVE A
VENT...I DRILL & TAP MY OWN HOLE & ADD A VENT....GOOD LUCK....ALSO, IT COULD BE THE PUMP....HOPE NOT...
A tailhousing vent is illegal NHRA. Why BTE doesn't I'd imagine.
Don't ask me to explain why, the owner of Reid went through it with me, I can't remember, seemed like a one off scenario NHRA came to this rule on.
The history of my 400 woes is this: I had one that never had fluid out of the vent and I didn't have a catch can for many years. I broke the case in the bell area so I bought a used case from Trans Specialties and had my internals freshened and installed. That's when my leaking out of the vent tube started. I called TS and they said it's probably the pump and bring it back. I told them my receipt says "new pump". That means the pump was surface cut. I put a little over 300 runs on it and just had it freshened up. I'm not sure if this builder did anything with the pump. I'll pull the vent and hope it works if not, I'll just drain the tank every week and pour the juice back in.
Posts: 466 | Location: Maryland | Registered: January 23, 2007
Originally posted by Ron Gusack: The history of my 400 woes is this: I had one that never had fluid out of the vent and I didn't have a catch can for many years. I broke the case in the bell area so I bought a used case from Trans Specialties and had my internals freshened and installed. That's when my leaking out of the vent tube started. I called TS and they said it's probably the pump and bring it back. I told them my receipt says "new pump". That means the pump was surface cut. I put a little over 300 runs on it and just had it freshened up. I'm not sure if this builder did anything with the pump. I'll pull the vent and hope it works if not, I'll just drain the tank every week and pour the juice back in.
It needs a liberal vent, they all do, try it. I have a certain way I fix the vent on these tanks. I don't like the vents on them typically. The vent needs to be liberal (Not restricted).
I've run a turbo400 in my race cars for nearly 30 years and they never pushed out any fluid nor where they plumbed to a catch can and they all used the oem vent and location. you have a problem with your trans. BTW, my Rossler Super Stock turbo 400 is for sale.
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Posts: 13522 | Location: NJ | Registered: August 20, 2000
Over 20 years ago I made a catch can out of an old radiator can. I drilled a 5/16 hole in the top so it could breath. Anytime the transmission is out or serviced and refilled it spits out what it doesn't want. After that I don't have to even check the can. This is connected to the factory vent.
The th400 in my car is from 1992 when the car was built. I’ve had it serviced 2x since I purchased in 2007. Aftermarket planetaries and 1+2 transbrake. Stock vent, no catch can and no fluid loss. Fill to lower fill mark on dip stick when trans at 120*.
Posts: 2722 | Location: 53056 | Registered: December 30, 2009
On my own 400s and a few friends we installed a hose nipple in vent and ran hose to a overflow can on firewall plump hose into bottom if they push fluid out when car shut off will drain back into trans
Posts: 422 | Location: Natick MA | Registered: November 15, 2017
Is there a way to test this issue without making passes? Powerbrake on the trailer till ATF temp is X amount?? I thought about finding a local builder with a trans dyno to make sure it's fixed but then I thought they can't do anything I can't do with it in the car. Does the pump have more pressure as the R's go up?
Posts: 466 | Location: Maryland | Registered: January 23, 2007
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