Help diagnosing transmission issue *jolt*

[eastmentCTD600]

2004. 5 2500, QC, LB 4x4.



I have an issue which i believe is rooted in the transmission. It goes like this...



1. ) From a dead stop, transmission warm (140+ degrees), apply throttle lightly, truck moves forward 5 to 10 feet then a small jolt is felt like something is deciding to engage fully. This feels amost like a bad U-joint or slack in the driveline, but I can assure you, there is no slack in the driveline.



2. ) When coming to a stop a small jolt can also be felt just before the vehicle stops moving.



3. ) From a dead stop if you apply the brake to keep the truck from moving then apply the throttle, no jolt.



4. ) From a dead stop if you apply some brake, but not enough to hold the vehicle still, and then apply throttle to overcome the break, no jolt.



Questions:



1. ) Has anyone expereinced this before?



2. ) What mechanism in the transmission controls clutch pressure at/during the transition from moving to not moving and vice versa, I'm assuming this "system" or "part(s)" has something to do with the jolt I feel.



Anyone have any ideas or other things to try?

 

[cerberusiam]

Yep, swapped out the drive shat to a 1 piece and problem gone. It was almost like a dead spot when starting out easy. Truck start to move then hesitate then move again, but only under light throttle unloaded. Get after it hard and no problems, hang a load on it no problems.



In my case I think the hanger bearing was deflecting too much.

 

[eastmentCTD600]

Yep, swapped out the drive shat to a 1 piece and problem gone. It was almost like a dead spot when starting out easy. Truck start to move then hesitate then move again, but only under light throttle unloaded. Get after it hard and no problems, hang a load on it no problems.



In my case I think the hanger bearing was deflecting too much.

I'm not sure that is the problem but will examine it later. Just to be clear, I can take my foot off the brake roll forward 20 - 50 feet, maybe more an as soon as I apply throttle I get a jolt. Does this still fit with your experience?

 

[eastmentCTD600]

Where did you get your one-piece driveshaft, how much, and is it aluminum?

 

[MStaggs]

I have a similar problem but only when coming to a stop.

It seems like there is a pretty good jolt (clunk) when it down shifts to 1st gear.



On my truck that is the only time it does it but it does it every time I come to a stop. Its pretty annoying.

 

[eastmentCTD600]

I have a similar problem but only when coming to a stop.
It seems like there is a pretty good jolt (clunk) when it down shifts to 1st gear.

On my truck that is the only time it does it but it does it every time I come to a stop. Its pretty annoying.

My issue is not related to downshifting. You can lock it in 1st and this still occurs. It when I come to a stop, and just the instant the vehicle stops moving is when it jolts, not related to a 2-1 downshift.

 

[cerberusiam]

I'm not sure that is the problem but will examine it later. Just to be clear, I can take my foot off the brake roll forward 20 - 50 feet, maybe more an as soon as I apply throttle I get a jolt. Does this still fit with your experience?

Sort of, any time you tried to accelerate from off throttle it would have a little hitch like something was slipping. Under heavy throttle or loaded it was not noticeable.



Since it acts the same way in manual first it is likely not a shift, but, could be slack in your transmission I guess. Thats what I thought mine was, possibly a TC going bad, until I swapped the DS.

Where did you get your one-piece driveshaft, how much, and is it aluminum?

Doghouse Diesel and yes they are all aluminum. Dodge OE part.