Think I blew the trans
Think I blew the trans I was at the track today, car left fine but at the 1-2 shift something broke. Engine hit the rev limiter and I have no forward or reverse gears. A friend thinks it may be the converter of front pump, I'm thinking it killed the trans.
Where should I start to look to check to see what happened?
thanks
Where should I start to look to check to see what happened?
thanks
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Joined: Aug 2010
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From: Ann Arbor, MI
Bummer.
Since you don't even have Reverse, it pretty much has to be the output shaft, the input shaft, input drum or the pump. Since the pump is not excessively strained at WOT, it probably is not the pump. (Correction: it seems the pump, particularly the rotor, is a failure point; see below.)
It can also be a broken flexplate or internals of the converter.
You can check the pump before removing the trans:
1. With engine off, check the trans fluid level.
2. Turn on engine and check trans fluid level again; if the pump is working (and flexplate not completely broken off), the fluid level should drop about one inch, even a bit more.
Obviously the trans and converter need to be removed. Once it is removed, checking the input and output shafts for breakage should be straight forward. The output shaft turns much harder in one direction than the other, but IIRC, when you turn it the hard way, the input shaft will turn too.
If the pump was OK in the dipstick test and the input and output shaft look OK, I would suspect the converter.
Perhaps someone can confirm or correct what I said; I may be overlooking something.
Since you don't even have Reverse, it pretty much has to be the output shaft, the input shaft, input drum or the pump. Since the pump is not excessively strained at WOT, it probably is not the pump. (Correction: it seems the pump, particularly the rotor, is a failure point; see below.)
It can also be a broken flexplate or internals of the converter.
You can check the pump before removing the trans:
1. With engine off, check the trans fluid level.
2. Turn on engine and check trans fluid level again; if the pump is working (and flexplate not completely broken off), the fluid level should drop about one inch, even a bit more.
Obviously the trans and converter need to be removed. Once it is removed, checking the input and output shafts for breakage should be straight forward. The output shaft turns much harder in one direction than the other, but IIRC, when you turn it the hard way, the input shaft will turn too.
If the pump was OK in the dipstick test and the input and output shaft look OK, I would suspect the converter.
Perhaps someone can confirm or correct what I said; I may be overlooking something.
Last edited by mrvedit; Jun 9, 2014 at 10:11 AM. Reason: Correction
TECH Resident
Joined: May 2006
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First, see if you broke the rear end. Second, remove the top line at the transmission and see if fluid comes out when you start the motor. Put the line in a bottle. It should put out fluid as soon as you start the motor. If no fluid, then the rotor in the front pump broke. If there is fluid, then the input shaft could have split open the aluminum input drum.
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
I guess I stand (or sit) corrected - the pump/rotor fails more often than I thought.
Removing the trans line is the definitive way to test the pump, but the dipstick level test with engine on/off is a simple trick I learned on this forum.
Removing the trans line is the definitive way to test the pump, but the dipstick level test with engine on/off is a simple trick I learned on this forum.
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Got the info on the failed parts. Broke where the input shaft goes into the drum. Getting some better parts installed, good thing I have a friend that owns a trans shop. He's a drag racer also so he knows what I'm trying to do with the car.
Should be fixed this week.
Should be fixed this week.
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Had my ws6 doing the same thing, wouldn't catch 3rd or 4rth ended up thinking it was the tps sensor then tried looking at the solenoids and it ended up being the internals of the trans so I just replaced it with a newer one for around 400$
Sonnax also makes a modified input drum and billet input shaft which we use in our black edition Its a very nice piece .
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Joined: Aug 2010
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From: Ann Arbor, MI
Its main "feature" is that it replaces the 3/4 clutch snap ring with a bolt-on end-plate. This allows room for one more friction/steel and should eliminate the "coning" problem that can otherwise ruin the 3/4 clutch when running higher line pressure.
No sponsor/builder is going to guarantee this solves the 3/4 clutch problem, but I know it is being used successfully in 700HP pickup trucks.