Automatic transmissions suck!
Racer
Joined: Sep 2008
Posts: 456
Likes: 0
From: FL
Car5car, Sliding has a FULL MANUL VB.
With the shifter lever in 2 it stays in 2 at 1000 rpm and at 10,000 rpm too, at wot or at idle or at part throttle.
If he decide to floor at 1200 (or at 2000 or at 4000 or at 6000 or at 7000 rpm in 4th gear, the trans must stay in 4th gear.
If it decide to start from a traffic light in 3rd, the car must start in 3rd.
With the shifter lever in 2 it stays in 2 at 1000 rpm and at 10,000 rpm too, at wot or at idle or at part throttle.
If he decide to floor at 1200 (or at 2000 or at 4000 or at 6000 or at 7000 rpm in 4th gear, the trans must stay in 4th gear.
If it decide to start from a traffic light in 3rd, the car must start in 3rd.
Team Owner
Joined: Feb 2006
Posts: 23,150
Likes: 117
From: San Antonio Texas
Is it really shifting into third and pulling the car or is it just revving up the engine and you think it downshifted. It sounds like it is loosing pressure and the clutch pack is releasing letting the engine wind up with no load on it.
Thread Starter
Drifting
Joined: Jun 2001
Posts: 1,625
Likes: 1
From: Zagreb, Croatia
because that happened to me a few years ago when my tranny
blew on highway. To tell you the truth, I'm not 100% sure,
but it feels like it downshifts, because revs go REALLY high
and REALLY quick.
Hmmmmm....... how can I make 100% sure?
Racer
Joined: Jul 2006
Posts: 315
Likes: 0
Now, that is a really good question! I assumed that it downshifts,
because that happened to me a few years ago when my tranny
blew on highway. To tell you the truth, I'm not 100% sure,
but it feels like it downshifts, because revs go REALLY high
and REALLY quick.
Hmmmmm....... how can I make 100% sure?
because that happened to me a few years ago when my tranny
blew on highway. To tell you the truth, I'm not 100% sure,
but it feels like it downshifts, because revs go REALLY high
and REALLY quick.
Hmmmmm....... how can I make 100% sure?
If the clutch is slipping, they are probably throwing off material. If you pull the pan and inspect the filter, you will either see a very clean perfect looking low mileage rebuilt unit or you will see a bunch of stuff that looks like sawdust in and around the pan and in the filter. I would think the amount of clutch material would depend on how much time they spent slipping if you know what I mean.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Would that (clutch pack slip ) also not happen if he hit it hard in a lower gear that uses the same clutch?
Instructor
Joined: Sep 2008
Posts: 136
Likes: 0
From: DFW TX
If the trans is working as a full manual then the quick rev would be caused by slippage.
Check your fluid level... you could be running low. This would cause the pump to cavitate at high load and thus the surge in RPMS.
Could also be you didn't put enough steels and clutches in the pack. Also could be that there is a restriction in the flow. Or that the valve is not opening all the way.
There is a myriad of problems. check for debris. Either way get the trans pressure tested and recheck your work on the clutch packs.
Check your fluid level... you could be running low. This would cause the pump to cavitate at high load and thus the surge in RPMS.
Could also be you didn't put enough steels and clutches in the pack. Also could be that there is a restriction in the flow. Or that the valve is not opening all the way.
There is a myriad of problems. check for debris. Either way get the trans pressure tested and recheck your work on the clutch packs.
Melting Slicks
Joined: Jan 2002
Posts: 2,238
Likes: 4
From: Milan
Now, that is a really good question! I assumed that it downshifts,
because that happened to me a few years ago when my tranny
blew on highway. To tell you the truth, I'm not 100% sure,
but it feels like it downshifts, because revs go REALLY high
and REALLY quick.
Hmmmmm....... how can I make 100% sure?
because that happened to me a few years ago when my tranny
blew on highway. To tell you the truth, I'm not 100% sure,
but it feels like it downshifts, because revs go REALLY high
and REALLY quick.
Hmmmmm....... how can I make 100% sure?
Try to put a very low speed in the constant "TCC unlock prevention Vehicle Speed"... say 55 mph.
Find a free road, go to a steady speed of say 65 mph (with the TC locked). Do a WOT.
Doing this you shoul have a better feeling on clutch slippage or real downshift.
-Beppe-
Thread Starter
Drifting
Joined: Jun 2001
Posts: 1,625
Likes: 1
From: Zagreb, Croatia
There is no slippage or downshift until I hit high rpms.
I can start in 4-th, and there won't be any slippage.
This problem occurs most often when I shift from 3-4.
I drive in 3-rd to ~ 6200 rpm, than I have to lift off
to get 3-4 shift, and then when I floor it again it
downshifts back to 3-rd or release clutch!?
I have 9 clutches (instead of stock 6) in 3-4 clutch pack
and I have set-up steels that way to get minimun clearance,
but within wanted limits.
I can start in 4-th, and there won't be any slippage.
This problem occurs most often when I shift from 3-4.
I drive in 3-rd to ~ 6200 rpm, than I have to lift off
to get 3-4 shift, and then when I floor it again it
downshifts back to 3-rd or release clutch!?
I have 9 clutches (instead of stock 6) in 3-4 clutch pack
and I have set-up steels that way to get minimun clearance,
but within wanted limits.
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Drifting
Joined: Aug 2006
Posts: 1,279
Likes: 0
From: Delray beach FL
My stock 91 is also acting the same.
Let say at 90 mph at 3500 rpm, if I kick down, the trans shift down to 3rd over optimal torque above 4500 rpm witch is not ideal.
At 4000 rpm in 4th, it can kick down and go red zone too.
With experience, you know how far to push the pedal and get the most of the 4th gear.
Until 3200 rpm in 4th gear, I know I can downshift and go into the torque peak.
Starting 3400 rpm, I am escorting the pedal according to torque instead of WOT. This makes the car accelerate even better.
Even if your rpm band is much wider, it still remains a 700r4 with congenital ghosts.
Let say at 90 mph at 3500 rpm, if I kick down, the trans shift down to 3rd over optimal torque above 4500 rpm witch is not ideal.
At 4000 rpm in 4th, it can kick down and go red zone too.
With experience, you know how far to push the pedal and get the most of the 4th gear.
Until 3200 rpm in 4th gear, I know I can downshift and go into the torque peak.
Starting 3400 rpm, I am escorting the pedal according to torque instead of WOT. This makes the car accelerate even better.
Even if your rpm band is much wider, it still remains a 700r4 with congenital ghosts.
Last edited by frenchyoliver; Oct 23, 2008 at 04:49 AM.
Instructor
Joined: Jan 2008
Posts: 163
Likes: 1
From: Idianapolis Indiana
Heres the problem. I dont wanna sound like an *** but you should have just spent the money on a full manual valve body. I have used shift kits a couple of times in the past and they will perform as advertised during moderate use, but when used HARD can do weird things sometimes. If you go back into the trans spend the 400 bucks on a full manual valvebody, remove the TV and the governor and be on your way. My full manual b&m shift kit on my 92 camaro absolutely will not down shift ever. Ultimately though I think you are going to have to go to a good transmission guy........again.
Thread Starter
Drifting
Joined: Jun 2001
Posts: 1,625
Likes: 1
From: Zagreb, Croatia
That was my first option that I wanted to go with, but after some
research, it looked like full trans pressure that is applied all
the time with full manual VB is reducing trans longetivity a lot.
For how long have you had your manual VB?
You don't sound like an ***! Every input and criticism is allways
welcome!
research, it looked like full trans pressure that is applied all
the time with full manual VB is reducing trans longetivity a lot.
For how long have you had your manual VB?
You don't sound like an ***! Every input and criticism is allways
welcome!
Instructor
Joined: Jan 2008
Posts: 163
Likes: 1
From: Idianapolis Indiana
I dont have a full manual valvebody I have a full manual shift kit from b&m. It ran for a year and a half behind a 383 sbc with 590 ft lbs torque, 3 months behind a 4.3l v6 and now its behind a 350 in my elcamino for the last 3 months. Mind you this trans has a the 13 vane pump, oversized accumulators and actuators and a high pressure valve but I havent done clutches yet and now that its behind a mild 350 Im not going to until it breaks. I never experienced this problem you have. As far as pressure increase damaging the trans this is false. The higher you line pressure the more clamping force you have and thus longer clutch life. I beleive TCI makes a full manual valve body for less than 500 bucks that should fix your problems. On mine the governor is ziptied together and just plugs the hole as it isnt used on mine. Same for the TV cable. Its just in there keeping dust out. Its a little annoying sometimes since this car is column shift and my friends dont like how it barks the tires in all gears.
Plus I cant remember who but someone is now making full pressure automatic valve bodies now. It operation of those the TV only controls shift point and not firmness. You might try one of these too.
Plus I cant remember who but someone is now making full pressure automatic valve bodies now. It operation of those the TV only controls shift point and not firmness. You might try one of these too.
