I posted a thread "crazy idle problems" but on further investigation I believe the TC is not unlocking when coming to a stop. You have to put all of your weight on to the brake pedal to stop the truck from moving and on occasion my friend said the only way to stop was to throw the tranny into nuetral.

My friend gave me some inaccurate info at first but his friend that drove the truck with these symptoms was a bit more mechanically inclined. The engine is bogging down a bit when this happens but you can tell the engine is trying to add power when it's getting bogged down like you are trying to power brake the engine at the drag strip. The only code is P633 which I guess has to do with the SKIM and doesn't apply and the truck otherwise works flawlessly.

Anyone have any ideas on possible sensors and/or other causes and possible remedies?

Thanks,

Joe

 

on cars I've worked on in the past, a failed lockup solenoid would cause the engine to kill. but i don't think it would on a cummins but close...... i suppose if you really mashed on the brakes until it stopped.... any way here's a picture of the valve body and a possible answer to the problem.
it could be the TCC solenoid or the converter clutch lock up timing valve.
but i would bet it's the solenoid... to change it, remove the trans pan and it should bolted to the valve body and have a couple of wires that plug in to another harness....


http://cgi.ebay.com/ebaymotors/Solen...Q5fAccessories

 

here's a link for what you need
http://www.transmissionpartsusa.com/...-00053392d.htm

 

John,

His truck is a 2006 with an automatic.

Joe

 

John,

Thanks for your help. I am sorry for the confusion on the tranny. My friends truck in an 06 so he should have the 48RE tranny I believe. If you have that manual as well can you scan those pages for me and email them to me? I am 99% sure you have the right solenoids identified as the problem but I am also wondering if the solenoids could just be receiving a possible incorrect signal from another sensor commanding it to lock up. Or do you just think the solenoid is getting stuck in position when it should be releasing as its an intermittent problem?

Thanks

Joe

 

If the converter is really locking up it will kill the engine now. The solenoids are normally open so sticking closed is extremely rare and unusual. The only other way they could partially apply is a rubbed wire but a dead short will set a code. Frequently the descirbed problems is a bad TC but definitely try the simple things first.

 

What part in the Torque Converter fails to reproduce the symptoms?

Joe

 

One more question on the solenoids. To stay locked, is/are the solenoid(s) looking for a ground or 12V signal from the computer?

 

Ground, the solenoids are powered 12V all the time and the ECU simply grounds the circuit to activate.

Not sure what th epart is called internally but if the seals go in the TC it will bleed pressure into the lockup circuit and cause partial apply.

 

I have the same problem in my 03 with the 47re trans took it to 3 trans shops they all said converter i figured b s so i bought the full noid pack for the trans and changed everythings out did the same exact thing now im saving up for a decent billet cover converter