torque converter wont lockup

Driving today and noticed the torque converter isnt locking up at all. I tried the manual lockup switch and it has no effect. Bad converter or bad electronics? What should i try.
 

dogboy

uk typhoon
Re: torque converter wont lockup

sorry dont know the answer but wanted to know what/where manual switch is...something you have put on or am i missing something? thanks mike
 

jwaller

Evil Genius/SyTy Guru
Re: torque converter wont lockup

you wanr to connect the top left and top right pins on the ALDL connector. try that and see if it's locking. if not then you could have several problems.

bad VB pressure switch
bad TCC solinoid
coolant temp sensor
brake light switch
TCC circuit wiring
DRAC box failure
 
Re: torque converter wont lockup

It doesnt lock up when the aldl wires are jumpered.
If my brake lights work, does that mean its not the brake switch? There are two switches on the pedal. Which one, top or bottom.
Which coolant sensor, engine or for the transmission itself.
I will swap out the drac box and see if that is it.
Is there a way to check the tcc solenoid without pulling the tranny, is it accesible through the pan?
 

jwaller

Evil Genius/SyTy Guru
Re: torque converter wont lockup

syclone0209 said:
It doesnt lock up when the aldl wires are jumpered.
If my brake lights work, does that mean its not the brake switch? There are two switches on the pedal. Which one, top or bottom.
Which coolant sensor, engine or for the transmission itself.
I will swap out the drac box and see if that is it.
Is there a way to check the tcc solenoid without pulling the tranny, is it accesible through the pan?

if your brake lights arent on all the time you are probably ok with that.

coolant temp sensor for the motor. if while watching datamaster, you dont see the temps rise to normal, then the ecm wont command the TCC to lock.

if your speed--o--meter is working then your drac is probably fine too.

you can check the TCC sol, which is removeable by pulling the pan, by shaking it. if it rattles its fine. if you dont hear the rattle then it's stopped up and needs replaceing. no sence in not replaceing it once your in that far. only 2 bolts hold it in once the pan and filter are down.
 

mrweelr

New member
Re: torque converter wont lockup

coolant temp sensor for the motor. if while watching datamaster, you dont see the temps rise to normal, then the ecm wont command the TCC to lock.

What constitutes a "normal" temperature? My TCC never locks and I've already replaced the TCC solonoid and verified it's getting the correct voltage with the ALDL pins jumpered. My old stock transmission and TC locked just fine, but ever since replacing my trans with the RPM and TCI converter, no lockup...ever. I did do a bunch of other upgrades when I replaced the transmission including relocating the coolant temp sensor on the driver's side head to the old turbo coolant port at the front of the intake. Datamaster shows coolant temps ranging between 165 to 180F. I have a 160F t-stat and dual ramcharger electric fans in my truck and I'm wondering if my low coolant temps could somehow be causing this problem? I have a Phil Long 50# v5.50 chip. Ideas?
 

ABOSS

New member
Re: torque converter wont lockup

Just want to know how can you tell the TCL is working, does it shift harder? I would like to test it..
 

wheels

Donating Member
Re: torque converter wont lockup

ABOSS said:
Just want to know how can you tell the TCL is working, does it shift harder? I would like to test it..

Get above 32?MPH and tap the brakes, the RPM's shoud rise when it unlocks and then fall back down when it locks back up. If you are accelerating normally at operating temperature it should lock up at 32ish MPH. Kinda feels like another gear sometimes.
 
Re: torque converter wont lockup

pulled the pan and the solednoid was stuck. replaced it and the converter still acts the same. In 4th you can tap the brake and the rpm rises about 100 to 200 maybe. At highway speed you can really tell, 65 mph 2400 rpm with almost no load. small amout of throttle to accelerate and its 2800 to 3000 rpm. Are the tc clutches bad?
 

jwaller

Evil Genius/SyTy Guru
Re: torque converter wont lockup

mrweelr said:
What constitutes a "normal" temperature? My TCC never locks and I've already replaced the TCC solonoid and verified it's getting the correct voltage with the ALDL pins jumpered. My old stock transmission and TC locked just fine, but ever since replacing my trans with the RPM and TCI converter, no lockup...ever. I did do a bunch of other upgrades when I replaced the transmission including relocating the coolant temp sensor on the driver's side head to the old turbo coolant port at the front of the intake. Datamaster shows coolant temps ranging between 165 to 180F. I have a 160F t-stat and dual ramcharger electric fans in my truck and I'm wondering if my low coolant temps could somehow be causing this problem? I have a Phil Long 50# v5.50 chip. Ideas?

I'll have to check to be sure but stock calibrations need about 150deg before they lock, I set all my chips to about 130deg.
 

mrweelr

New member
Re: torque converter wont lockup

Found out my torque converter was bad. The TCC locks hard with the new billet 9/11 converter.
 

alwayscode390

pppssssshhhhhtttttttttttt
Re: torque converter wont lockup

wheels said:
Get above 32?MPH and tap the brakes, the RPM's shoud rise when it unlocks and then fall back down when it locks back up. If you are accelerating normally at operating temperature it should lock up at 32ish MPH. Kinda feels like another gear sometimes.


I think mine is at around 39mph because it always feels weird there....I still am baffled by this torque converter science :( ---
 

mrweelr

New member
Re: torque converter wont lockup

If you remove the input shaft checkball and retainer from your trans, you'll feel a much firmer TCC lockup. Combine that with solid motor mounts and a fully-built trans and it'll be even more pronounced. I'm having Phil Long reprogram my chip to raise the minimum TCC lockup mph from ~45mph to 55mph. It really does feel like another gear. I don't even put my truck into 4th unless I'm on the freeway since it lugs the motor big-time.
 
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