Is it downshifting or the torque converter unlocking?
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Senior Member
Joined: Aug 2001
Posts: 945
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From: NJ
Car: 1990 Pontiac Firebird
Engine: 3.1L v6
Transmission: Automatic
Is it downshifting or the torque converter unlocking?
alright sometimes ill just be crusing along ~50mph. i have my foot barely on the gas and the engine is humming along nicely at like 1600-1700rpm. once i start giving it more gas, id say just before half throttle, the rpms jump up a little and if feels like im out of the power band or something, doesnt feel as strong. is the torque converter unlocking or is it downshifting? when i go wot and it downshift it feels a lot different, but of course the engine is turning more rpms so when it does downshift u can feel the power is there. but just crusing and it does this it feels like its not getting the full power to the wheels. is this normal? im pretty sure its going from 4th to 3rd, or something is happening to the torque converter.
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Joined: Sep 2001
Posts: 1,195
Likes: 0
From: Flowery Branch, GA
Car: 1985 Iroc-Z
Engine: 1 BA 305 TPI
Transmission: Probuilt 700R4 - 2800 Stall Midwest
Axle/Gears: 3.42
From the way it sounds you have a 700R4 and it is downshifting. Mine would do that sometimes. It acted like it was searching for the right gear. I think this may be normal for the 700R4. I believe there is a way to prevent it. I have read somewhere on here about changing one of the valve or something like that would stop it from doing that. Maybe if Pro-Built reads this he can help you or you could give him a call. He is very helpful.
Supreme Member
Joined: Nov 1999
Posts: 2,860
Likes: 3
From: NE
Car: 82 camaro SC
Engine: 350
Transmission: 700r4
What is the rpm change? Unlocking coverter will be just a few hundred rpms, downshift will be much more. Another way: When you feel the slight kick-down, pull the shifter down into 3rd--if it makes a difference you were in 4th, no change you were already in 3rd. Something else....drive normally and slightly push the brake pedal down--you should feel the TC unlock. My 'guess' from what you describe is that it's just unlocking the TC. Most 700R4's I've used first unlock the TC, then downshift when adding more throttle gradually.
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