have an 01 w/5.2, truck will have terrible vibration under light load like pulling a very slight hill. when this happens the rpms raise slightly (@50rpms) kick down and it goes away. Have already replaced the plugs, wires, distr. cap and rotor button. Any ideas?[:@]

 

Sounds like the TC clutch is letting go. What does it feel like when you take it out of OD?

... it IS an automatic, yes?

 

does it almost fell like hitting a rumble strip on the highway? if so it could be the tc clutch or the od unit itself may have a broken snap ring which does cause a good vibration that almost fells like a misfire.

 

I had a similiar problem with my truck this summer. I cured the probem by installing a shift kit. The shift kit improves fluid flow through the valve body, and for whatever reason, this fixed it. My tranny mechanic claimed that it would help and he was right. That vibration annoyed the heck out of me, it was always around the 50 mph mark, usually in OD lockup,but sometimes at a lower speedin 3rd with the TC locked up. Haven't had the problem return in about 7 months of use.

If you think it is the tranny, it wouldn't hurt to install a shift kit. You need to drop the pan and drain the fluid. The labor isn't that much to pull down the valve body and install the kit. Put in new fluids and filter and you should be ready to run. The kits start at around $100 depending on the brand and you can set the level of firmness at time of installation. Its a good investment if you need to spend money on tranny maintenance and it will help increase the life of the transmission.

 

I had the same problen and it ended up being the torque converter.

 

It sounds like torque shudder or tranny slipage.

 

Seems like everyone thinks it's a TC. I hope not. I have 95000 miles now and it was rebuilt at 57000 miles already. Love that Dodge tranny. Any one have a clue what it may cost to fix? It does feel like a rumble strip. It does happen mainly in OD. Although I have noticed very slightly in 3rd geat I think.

 

Here are twoposts that I originally wrote when I was experiencing similiar problems. I also noticed a raise in the rpm's that went away after getting the shift kit. Read them if you want and give it some thought. Your problem could be one of several things.
https://dodgeforum.com/m_553041/tm.htm
https://dodgeforum.com/m_553044/tm.htm

 

Before you go with the clutch i FIRMLY suggest just changing your Tranny fluid and filter. I had this same problem just last week. I bought the filter kit and ATF+4 fluid from Advanced Auto and did the change myself. Drove the truck the next day.. Went up a hill and it still happened, HOWEVER after about 3min of driving i went up and down slight hills with OD on and the problem hasnt happened since. Going 3 days strong so far. All and all it cost me $45 and tranny fixed. Start there! (*** I hate rubber gaskets***)

 

Well I spoke to my local tranny shop and got a great tip. This is known as Torque Converter Flutter/Flux. He said 90% of the time nothing is wrong with the TC, it just needs lubricating. He recommended a GM additive to fix it. The additive is "Limited Slip Axle Lubricant Additive." I put it in and less than a mile the vibration was gone. It is 4oz of additive and costs approx. $15.00. I hope this may help anyone else with this problem.