Torque Converter Lockout Operation

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Mkweaver1958
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Posts: 64
Joined: Tue Nov 06, 2018 8:00 am

Torque Converter Lockout Operation

Post by Mkweaver1958 »

How hard is it to replace the Torque Converter Lockout solenoid?
When I was under the Indy to change the trans fluid I found the wires to the solenoid were left unplugged.
I re-connected it and tried to drive the car and immediately found out that its not releasing when stopped.
Is there a real benefit to it or should I just leave well enough alone?


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ifixalot
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Joined: Tue Dec 26, 2006 10:56 am
Location: Deerfield Illinois

Re: Torque Converter Lockout Operation

Post by ifixalot »

It's under the side cover of the trans. I did it on my daughter's 90. It was tricky to get the cover off because it's close to the frame but I was able
to jack the engine up enough to do it. Once the cover is off, the solenoid is pretty easy to change. In my case, I cut the wires and re soldered them
back together. You can leave it unplugged but it would effect gas mileage by a couple mpg. If you don't drive it that much, it's probably not worth the effort.


Mkweaver1958
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Posts: 64
Joined: Tue Nov 06, 2018 8:00 am

Re: Torque Converter Lockout Operation

Post by Mkweaver1958 »

Thank you Ifixalot, I drive it daily so I may just bite the bullet and fix it.
I now have another vehicle to drive when the Beretta is down.


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Rettax3
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Re: Torque Converter Lockout Operation

Post by Rettax3 »

My Yellow Indy still has the TH125C auto with torque-converter lock-up. If I don't 5-speed swap the car first, I will install an override control to activate the TCC manually. Cruising at 35MPH, it is right on the cusp of activating, and the RPM drop with it engaged is very noticeable. I drive the car between 35-40 over half the time, and that is the range it may or may not activate (38MPH). It drives me nuts, and even at 40, I cannot climb a hill without it kicking back out. I don't intend on bogging the engine down enough to hurt it, but a light load is fine, especially on a 3.1 MPFI. I wouldn't be able to stand the TCC being disabled... You will save engine wear and gas mileage, as ifixalot said. The repair will pay for itself.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
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