hi, my 94 2500 ram with a 360 v8 and an auto trans shakes very bad when it is in overdrive and im giving any kind of throttle. it shifts fine into every gear and i just replaced the u joints. i think it might be the torque converter but i want to see if you guys have a different opinion. thanks for anything you come up with

 

It isn't speed dependant is it? I was chasing a similar issue down, but it only happens at 70-75MPH. Turns out it was all four tires unbalanced.

It could be the TQ, but check the cheap options first.

 

1. Does it shake in any other gear?
2. Does it shake in any certain RPM range?
3. What happens if you maintain your highway speed (when shaking) and then disengage OD?

 

so it only shakes when its in the O/D gear, or just when O/D is on?

 

Mine began to do that in O/D when my heads went bad. I drove around with the O/D off but soon began to do it then also.

 

If it's only in OD, I would drop the trans pan and look for pieces of metal, especially pieces that look like a snap ring.

If it happens at a certain RPM, I've heard of the driveshaft losing a balancing weight or two and causing this. If you just replaced the U-joints and immediately started to act up after that, I'd recheck my work.

 

It would make sense to me that when in OD there is not as much torque on the drive train taking tension off of parts allowing any unbalanced or sloppy components to kind of do what the want . I don't think it is in the tranny, sorry to contradict you squirrels but I don't know how that would make the truck shake if something in the tranny was that bad I would think that the truck would not be shaking but in the back yard wating for my taxes. Sounds like a suspension issue, go figure. Maybe drive line. I have the same issue, and just found that both my upper and lower ball joints are gone on the drivers side but mine is more than likley tire balance. Or worn out front end parts.

 

Uhh, your trans actually works harder in overdrive then it does in normal gears. that's why they tell you to switch it off when you tow.

Just because the engine RPM's are lower doesn't mean the trans isn't doing more work.

The engine RPM's get reduced to a ratio of 0.69:1 in OD because the trans does the extra work to make the truck maintain the same speed at a lower engine RPM. If your engine's running 2000 rpms in OD, your trans is running like it would at about 2900 RPMs in 3rd gear at a 1:1 ratio. At 2500 engine RPMs, your trans is outputing about 3623 RPM's worth of work. The driveshaft spins faster too.

The only part of the drivetrain that gets a break in OD is your engine.

A bad snap ring can cause poor or no OD engagement, an unbalanced driveshaft can cause a type of "harmonic wobble" at certain RPM's. If the OP drives his truck conservatively, he may not ever reach that specific driveshaft RPM range until he gets into OD.

If might also be a failing OD solenoid or sensor. It also could be the TC as the OP suspects. Could be a lot of things including the suspension, but the OP hasn't reposted.

 

Mines does the same thing after i've been splashing around in too much water

 

sounds like a drivline vibration to me. If the tires lost a weight or a cord is seperating they will cause a vibration as well.