bose901

I've been dealing with a locked up tc for a while now. Its locked up even with the the solenoids disconected, so i'm thinking it must be a mechanical problem. I just upgraded the Valve body thinking i might have had a stuck valve but that didn't fix the problem.
Does anyone know if the torque converter could fail internaly and cause lockup? It's not siezed because the truck can coast (free wheel).

Also, It's a 96 1 ton with 22k miles with a 47re. Other than the tc always in the lock up it shifts fine...

sweeney186

Yes your TC can fail internally

oldblues

hi
maby call some of the verter mfg recomended on here and ask a few questions ?
that would be my next move !

also ammaco , cotman ect some have a free diagnostic deal , but i would get more than 1 opinion !

let us know ???

hink

Then that tells me that the TC is not locked up. If the TC is locked all of the time it will be like trying to stop a manual trans. w/o pushing in on the clutch. What makes u think it's locked up?? or am I misreading ur question??

bose901

hink,
good question... you came to the same conclusion that i did after reading up on torque converters last night. it can't be in lock up be cause it free wheels (sometimes I over look the obvious things). So last night if took it out for another test run, sure enough when it got into OD and hit the right speed, it "locked up". The only way i could tell is because it wouldn't "freewheel". In other word the tc lock-up is working as it should. But the truck still acts like its locked up all the time. It stalls at 0mph when in gear and has no torque multiplication or "slip" in the tc. So now i think its the stator or stator one-way clutch. I ordered a new tc from suncoast this morning and with any luck i'l know by this weekend.... either way the stock tranny drives poor, so the new VB and TC wont be a waste, just expensive...

thoughts?

j-fox

You could have a seal damaged or leaking at the rear of the pump. This can allow pressure to apply the clutch. A teardown is in order to verify.

bose901

j-fox,
Wouldn't that apply pressure to the lockup clutch which would cause lockup in both directions and not allow it to free-wheel?

j-fox

The trans can freewheel because of the over running clutch in the case! That is why we need to use manual low to get engine braking at slow speeds!

bose901

but i can feel a clear difference in the amount of free wheeling when the TC clutch locks and unlocks... its night and day...

hink

I don't think this statement is true. You have to use a lower gear just for that reason--because of the slower speeds--since a higher gear is just that and does not add much "braking" power at slower speeds, but I don't know for sure so I'm not gonna push my argument. You've stated this a couple of times, but ur original question/statement says that you think the TC is locked up, so I'm not sure what ur tryin to say. I guess I don't understand ur problem.

bose901

Hink,
When I started the post I thought the TC clutch was always locked up because the engined RPMs could not run higher than the tranny rpms, this would also cause the truck to stall when I put in into gear unless i gave it some fuel to get it rolling. But then It took it for another test drive and noticed that the engine and tranny were not truely locked and the truck could freewheel meaning the tranny rpms could out rev the engine rpms like when you coast.

Because the TC clutch should fully lock the engine and tranny in both directions, I started doubting the tcc as the cause of my problem. To test this I got up to the speed at which the TC would normaly lock up and it aparently did as it would no longer freewheel untill the tcc unlocked. So now I believe the tcc is working as it should and something else is causing the problem.

I'm now leaning towards the stator or stator one way clutch in the TC and was hoping someone could tell me if this made sense.

I hope this is clear...It's kinda hard to discribe...

Fueling around

Raise your idle speed so it doesn't stall when you put it in gear.
If the converter clutch was locked from start the vibration would rattle your fillings loose.
If the stator clutch was frozen it would only cause a problem with fluid coupling when the engine & tranny rpm are closer. The stator uses the sprague to stop for torque coupling.

bose901

What if the sprag was bad? I'm certainly not getting any torque multiplication... Either way, I've got a new TC coming from Suncoast. I was just hoping someone could tell me that my symptoms sound like a TC problem. I'm not planning on doing a rebuild as the tranny only has 23K original miles. But if it's something in the tranny I'd rebuild it while it's out.

As I stated in an earlier post, I already installed a new VB from Suncoast and it made no difference (I didn't think it would) but I was planning on upgrading it anyway. Other than the inability to create torque multiplication it seams to shift fine...

bose901

it was the torque converter... runs better than new now.....

hink

Good to hear.