Weird TC problem

[x MadMAX DIESEL]

For some reason my TC will not lock up cruising. With a full duty cycle I can slip it to any rpm I want. If I'm full throttle seems to hold fine, takes about 2 seconds to lock but it does.

This is the same TC that was sent back for inspection because of ALOT of TC clutch material in the trans filter. They opened it up and said it looked fine and welded it back and sent the same one back to me (kinda was disappointed by that choice being that It was only about 1 week old, felt they shoulda sent a new one)

Anyways what the heck is up with that, any ideas on the problem?!

 

[paint94979]

/which converter are you running?

 

[x MadMAX DIESEL]

ML

 

[Mike L.]

How did the rings look on the stator support ( pump shaft )? Check it with a Tech 2 and see if the converter totaly locks. You will see it go to 96 or 97 %. Then look at the RPM slip after it locks and it better be at 0. If the scanner shows 96/97% that means it recieved full pressure. If it shows a lesser number there is something else wrong and not the converter.

 

[Cougar281]

Actually, the max duty cycle for the 6-speeds is 65.625%, whereas with the 5 speeds it was 98%. Not really sure why, but I'm assuming it has something to do with the different PWM frequencies between the two.

 

[x MadMAX DIESEL]

I used EFI live to log it already. Cruising it has a duty cycle of 65 but I can slip it to any rpm i want like I've said. I tried to go full throttle and it seems to lock up with about 10 max slip (id say is fine over the amount of rpm?) I've had trouble with the ML before already and this is the same exact converter that messed up.

 

[x MadMAX DIESEL]

Hmm went out for a spin and everything seems fine

 

[x MadMAX DIESEL]

Well new info. Just went out and did a boost launch left at 2000 rpm. Once it took off power kinda fell off and then came back. Driving back home I dont have a locked TC when its being commanded in o/d. Stopped and turned off the truck, opened doors etc. waited for it to lose all power. Then restarted and it seems fine again, no DTCs.

 

[Mike L.]

Well new info. Just went out and did a boost launch left at 2000 rpm. Once it took off power kinda fell off and then came back. Driving back home I dont have a locked TC when its being commanded in o/d. Stopped and turned off the truck, opened doors etc. waited for it to lose all power. Then restarted and it seems fine again, no DTCs.

How about you give us more info as to your power and mods. Guessing at what you have does not cut it.

 

[x MadMAX DIESEL]

I have EFI Live, Suncoast GMax 6, ML TC. The trans tune is stock

 

[Brayden]

We built the trans... Pulled it back down and inspected, sent the converter to Terry, and then cleaned everything up and reassembled.

Ben are you running my tune or something else again? It locked, and ran well with my tuning, IMO.

 

[x MadMAX DIESEL]

Im still running yours. It works totally fine as long as i dont launch it hard. I just recently found out If i do a boost launch it will kinda lose power then it comes back. It Feels like the TC was locked at the track but maybe not, it did the short power loss a few times there.

If i keep the truck running after the boost launch it wont lock up cruising, but does WOT. Even if I have full duty cycle or not.

If I kill the truck and restart it it all works fine again. and it will lock fine cruisin or WOT

Just after the boost launch it does this

 

[x MadMAX DIESEL]

I really wish I could go log it for you guys but Im having trouble with BBL (http://forum.efilive.com/showthread.php?13832-Trouble-loading-pid-selection-to-BB)

 

[Mike L.]

You need a locker if you're running any kind of power. Your problem is not the converter and sending it back was a waste of time and money.

 

[x MadMAX DIESEL]

You need a locker if you're running any kind of power. Your problem is not the converter and sending it back was a waste of time and money.

Waste of time and money? there was alot of clutch material, why would I not send it back in?


Having a lock up controller shouldnt affect it either, its CRUISING and not locking up with full duty cycle.Its not like its not locking because it sees too much slip, I can let off the throttle so there is no slip and it still doesnt lock.

 

[Mike L.]

Waste of time and money? there was alot of clutch material, why would I not send it back in?


Having a lock up controller shouldnt affect it either, its CRUISING and not locking up with full duty cycle.Its not like its not locking because it sees too much slip, I can let off the throttle so there is no slip and it still doesnt lock.

What color was the clutch material?

 

[x MadMAX DIESEL]

I don't remember off hand it was darker, I think I remember them saying it was non magnetic. Best guess was it was from the TC

 

[Mike L.]

I don't remember off hand it was darker, I think I remember them saying it was non magnetic. Best guess was it was from the TC

Restricted heat exchanger in the radiator can cause this and would explane dark color if you are correct. Get a Tech 2 installed and start comanding TCC and see what happens. Boosted launches make no difference on the converter clutches. Boosted launches when running close to 600hp will make a difference and inhibit TCC.
For your information, I have not seen clutch problems with SC, ATS, or PI. I have seen plugged heat exchangers, notched stator rings, broken rings, and problems with the converter flow valve. Tech 2 will tell you right away.

 

[x MadMAX DIESEL]

Have any idea how a boost launch could affect it though? The thing I dont understand is that it commands lockup and doesnt___that makes me think its mechanical
But
restart the truck and all is fine___ that makes me think its electronical

Its confussing lol

 

[paint94979]

Have any idea how a boost launch could affect it though? The thing I dont understand is that it commands lockup and doesnt___that makes me think its mechanical
But
restart the truck and all is fine___ that makes me think its electronical

Its confussing lol

Welcome to the world of Allison lockup difficulties... it is not a mechanical problem from the converter or the kit.