No lockup on 700R4?
Thread Starter
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
No lockup on 700R4?
I'm not a tranny man. But it appears to me that the Torque Converter lockup clutches are gone. What else could it be?
The problem is no more torque converter lockup. I had lockup in fourth gear only. I checked right at the tranny plug and it gets 12 volts. So I pulled the pan and bought another lockup solenoid. When I plugged it in it would pick and unpick just like it should. (Later I tested the original and it also works fine)
Is there anything else in the circuit? The oil was again super clean without any sludge in the pan. I found out that the vendor will refurbish the high end converters for @ 1/3 the cost of the new item. Which is kind of a nice warranty program
The problem is no more torque converter lockup. I had lockup in fourth gear only. I checked right at the tranny plug and it gets 12 volts. So I pulled the pan and bought another lockup solenoid. When I plugged it in it would pick and unpick just like it should. (Later I tested the original and it also works fine)
Is there anything else in the circuit? The oil was again super clean without any sludge in the pan. I found out that the vendor will refurbish the high end converters for @ 1/3 the cost of the new item. Which is kind of a nice warranty program
Race Director
Joined: Feb 2004
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Hook up a scanner and see if the ecm is commanding lock up.There is much more to the lock up circuit than the solenoid, and clutches. When I have one with no lock up, the first thing I do is the scan to check for the lock up command. If it is, then you can go from there.
Thread Starter
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I have gone beyond computer controls. I have a mounted toggle switch that supplies 12 volts to the solenoid. Which works fine. This is a racing type idea.
I just don't know if I might have some valve body problem so that I don't have oil to the lockup solenoid. I'm not sure if it is a direct shot from the pump or how it works. I'd hate to remove the TC and send it back just because it was something else.
It's an $1100 9.5 inch TC just like the higher end Vigilante and ProTorq TC's
I just don't know if I might have some valve body problem so that I don't have oil to the lockup solenoid. I'm not sure if it is a direct shot from the pump or how it works. I'd hate to remove the TC and send it back just because it was something else.
It's an $1100 9.5 inch TC just like the higher end Vigilante and ProTorq TC's
Thread Starter
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
This is not a new item. It was working and quit. I only used lockup out on the freeways and let off the gas to turn lockup on. I might have exceeded the holding power with my new motor even though the tranny it's self is rated at 800 hp. The TC is a 3 clutch 3800 stall
Le Mans Master
Joined: Apr 2000
Posts: 5,713
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From: Manassas VA
Originally Posted by Pete K
I do not have the book in front of me, but my memory is that the solenoid always has 12 volts and it is ground triggered by the ecm. If my memory is correct, you may need to feed it ground to lock it up.
Pete, you are correct. My tranny guy had me to check mine, term a has a constant 12 volts and d is ground.
Race Director
Joined: Feb 2004
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Originally Posted by gkull
This is not a new item. It was working and quit. I only used lockup out on the freeways and let off the gas to turn lockup on. I might have exceeded the holding power with my new motor even though the tranny it's self is rated at 800 hp. The TC is a 3 clutch 3800 stall
Race Director
Joined: Oct 2001
Posts: 19,653
Likes: 428
From: Melbourne Florida
Cruise-In IV Veteran
Originally Posted by Pete K
I understand. If the connections still run thru the brake switch, you can check it. It is often overlooked.
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Thread Starter
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I never saw any reason to have a brake unlock switch and still don't. It was long after my system had been in use that I even heard of that item.
Your driving down the road at high speed like in an open road race and your in lockup 4th gear doing 175 mph coming into a turn. Wouldn't you want engine braking along with disk brakes? Then what happens when your on the gas WOT still in 4th gear?
Your driving down the road at high speed like in an open road race and your in lockup 4th gear doing 175 mph coming into a turn. Wouldn't you want engine braking along with disk brakes? Then what happens when your on the gas WOT still in 4th gear?
