Strange vibration when NOT in 4wd

[Oktm]

I have a 2003 RAM 1500 with the 5.9 magnum, 46RE and a 241(I think) manual transfer case. At about 70 MPH I start getting vibration in the front. It sometimes is light vibration, sometimes feels like I am going over a washboard road. If I am going over 70 and let off the gas I get a brief distinct rumble for about half a second on top of the other vibration. Brakes do not seem to affect the vibration at all. The strange thing is that popping it into 4H the vibration instantly goes away. If I disengage into 2H and slightly let off the gas (giving the t-case a chance to disengage) the vibration comes back in full force. This seems like something with the front 4wd system, but I am not sure where to start. Any ideas? Thanks!

 

[Snake15eyes1998]

I would look into the front CV axles. Its IFS right? I can't remember when dodge went to IFS in their 1500s.

 

[Oktm]

It's the torsion bar suspension on the front independent I believe (have to look to verify, but I don't think it's a solid front.)

 

[Snake15eyes1998]

It's the torsion bar suspension on the front independent I believe (have to look to verify, but I don't think it's a solid front.)

The reason why I think it could possibly be your CV axles. My truck did the same thing BUT, mine did it only going 10-15 MPH. When I put it in 4H. It stopped, 2H it came back. I had a buddy standing way ahead of my truck, had him watch what was vibrating. He said the CV axles where flopping in the center. I had to look for myself. Had him drive it, and sure enough. They where flopping in the center once you got going 10-15 MPH. I replaced them and it's never done it again. This very well could be your same issue, or something completely different. But in my mind, putting it in 4-wheel drive would slightly stiffen up your CV axles because now they have a load on them. When it's in 2H, there turning but there's no load. Good luck man

 

[Oktm]

Thanks for the advice. When I get paid I will get a new set of axles. Now that I think about it when I was replacing bearings a while back one axle would not come out of the front diff. (I wonder if that is the culprit?) any advice for getting a stubborn CV to come out?

 

[Snake15eyes1998]

I had a hell of a time with my passenger side CV axle. I ended up ripping out the stub axle from the four-wheel drive actuator chamber on accident. It was so seized, it did not want to come off the stub axle. My advice would be a lot of PB Blaster and patience. PB it a few days every day before you actually do it. Good luck

 

[Oktm]

Good lord. Just found this post:
https://www.ramforum.com/threads/how-to-remove-a-stuck-cv-axle-shaft.121823/
Why!?!?

 

[Snake15eyes1998]

Good lord. Just found this post:
https://www.ramforum.com/threads/how-to-remove-a-stuck-cv-axle-shaft.121823/
Why!?!?

Thats one way to do it lol haha with my luck, I'd end up cutting into the splines. Thanks for sharing that link. I like the sliding hammer Idea. Never thought of that.