the outher day on the way to Florida from Texas, i pulled over to get fuel and as i approached the stop sing at the end of the off ramp i noticed the truck had a very rough idle, as i investigated further i noticed that the truck is idleing at 650-700 rpm and it feels like the tranny wont "stall" as if the converter is staying locked, trying to pull and not allowing it to 'Stall" . it does this even in reverse and if you hold the brake and take it out of gear( to neutral or park) the engine revs to about 1100 then fall back to 650-700 and idels fine. i finished the trip by putting the truck into neutral when at a light. any thoughts?
thanks gator

 

TC is bad and needs to be replaced. Common issue.

 

It happened to mine also. Right after I replaced the front band. Lucky for me I ordered my new trans and had only three week's wait until my trans would be replaced. On the way to get my new trans the converter began working again.

What you need to do is order your trans so when your truck really dies you're ready.

 

by tc your saying the converter is bad? im looking into the the relays and solenoids, not that i dought at all. i just find it weired that your going down the highway 80-85 for hours and without warning the converter takes a dump. the truck does have 180,000 miles on it and just before the trip i had the trans "flushed" by the dealer, i was trying to do the right thing, it had a bit of a odor and was a little like rust colored. i did not know if there was a chance of somthing getting into the valve body? today it seems as though the truck is not going into first at a stop light, i still feel like the converter is staying locked up pulling against the brakes and exelerating as soon as you let off the brake. i also feel the 1 to 2 quick shift and down shift at low speeds. thanks again for your input, it helps alot.
gator

 

Yes, the TC has internal problems. The TC has a sprag clutch that releases the stator hub under a certain mph to give the TC a stall. When this sprag locks up or doesn't not release fully you get the symptoms you describe. If it locks completely the truck will sit at a stop in gear and rev to 2100 rpms while trying to pull thru the brakes.

The lockup function is completely under computer control and is done via a spring loaded solenoid that is normally off. The ECU has to activate the ground circuit to activate the solenoid. If there is ANY failure in the electrical system or the solenoid jams the ECU sees this as an issue that will set a CEL and put the trans in limp mode. If the solenoid does not release lockup it will kill the engine immediately at a stop, or, when coming to a stop the rear end will literally jump off the ground as you try to stop. Mystery switches teach one a lot about what happens when lockup is engaged.

When the TC has no stall the ECU thinks the truck is going faster than normal and you get quick shifts. It is how the system works when it has issues.

Not going into 1st and the TC locking is quite likely the result of the flush. If it is not done correctly it floats garbage into the whole transmisison. That garbage will cause the sprag in the TC to jam and not fully release. It also gets into the governor pressure solenoid and jams it, hence the 2nd gear starts.

Since the delaer did it take it back to them and complain LOUDLY their service messed the trans up. You need a new TC, governor pressure transducer, and governor pressure solenoid at the minimum. If you can convince them they are the source of the failure they may feel obligated to replace the complete transmission.

Good luck.

 

Yeah Good luck!

I advise against flushing transmissions for this very reason! You may get lucky and whatever is sticking and clogging will break up and work its way out, or it may break the rest of the way and lock up completely.

At least if you go back to the 'tranny flush pushers' you will feel good yelling at them.

 

I have had no issues and I do fluid exchanges all the time. That claim is BS. TC break without fluid exchanges all the time. Lost Lake is one example.

One last thought. If someone tries to makeup for lack of proper service to an auto tranny by doing a fluid exchange, the damage was already done.

 

Somehow, I just can't reconcile those two statements in the same context.

TC's sprags fail without any contributory help, 06's seem to fail a LOT more than all the other years combined.

On the other hand, they fail with "flushes" occasionally also, as does the gov solenoid. If an exchange or flush is done incorrectly the chances of failures go up. Too many stories that mirror that epxerience to disregard.

 

thanks for all the help fellas, im still not 100% set on the converter. when im driving at lets say 40mph and let off the throttle the tach drops to 750rpm and you touch the throttle the tach jumps back to 13-1400 rpm. doesnt that show that the converter is unlocked allowind the trans to "free spool"? it does this in every gear, ive verified that the truck is indeed going back to first at a stop but it feels as though it takes a good amount of throttle to get rolling, if you stab the throttle it take a few seconds to build rpm but when it does it picks up well but still shifts iratically unless you leave the thottle wfo. thanks again guys. gator

 

If the truck is still trying to pull thru the brakes at a stop its the TC. That will also cause the delay in acceleration and excessive throttle to get moving. Sprag can be malfunctioning and work correctly at speed but still be an issue stopped. The key is if it is trying to pull thru the brakes and the engine starts to rev.

If the only problem you have is it is hard to get moving from a stop and slow to spool then it is probably starting in 2nd gear and it is the gov solenoid. That will not cause the engine to rev at stop or the truck try to pull thru the brakes.