Hi everyone,

I just picked up a 2000 Ram Van 1500 with 200k miles for cheap. Transmission was rebuilt at 190k. Front control arm was replaced right before I bought it. Starting to work through the issues and here's today's symptom...

At 40mph, the rear end feels like it's bucking or kicking around. The sound is a fast, deep dull thumping, probably 3 or 4 beats per second. Sensation is like the back end is bouncing up and down or kicking forward and backwards. This is ONLY when I'm giving it gas. When I take my foot off the pedal or shift into neutral, the sound and sensation disappear immediately. Give it a little bit of gas again and the bucking returns. Below 35mph, it's smooth as silk.

Tires are Trail Guide HLTs and look fairly new.

Any obvious culprits, or places to start looking? Really appreciate any guidance y'all can provide.

 

Try hitting the O/D off button on the end of the shifter while its doing that, does it stop?

 

Driveshaft U-joints could be worn.

 

Thanks for the help, HeyYou! And merry Christmas!

I tried turning off OD this morning and the hammering stopped immediately. Turn OD back on and it immediately returns. What's this mean??

 

Hey Alloro - There were three of the + shaped universal joints in the back seat when I bought it. Are those something you can get in without a lift?

 

Most likely its an engine misfire. When is the last time it had a tune up?? Plugs, wires, cap rotor?

 

New or used? If they're new, then the previous owner probably knew they needed to be replaced. Replacing them requires removing the driveshaft and having access to a press. If they are used, then they've likely been replaced.

 

Replaced spark plugs, wires, cap and rotor yesterday. Initial test drive feels noticeably better. Passed through the 40mph without feeling the original kicking feeling. Thanks again!

 

Don't forget the air filter.

If you have more than like 150K miles on it, O2 sensors wouldn't hurt either.

Here, let me spend some more of your money.

 

Don't forget the plenum gasket fix!
http://www.hughesengines.com/Index/p...p?partid=27091