Floor Board Thump At Speed - 1500hd

[dgore64]

I have an 02 1500HD 4x4 w/ just over 100,000 miles. Developed a thump in the front floorboards over the past 4 months. This occurs when traveling at various speeds over 35 MPH. Doesn't occur all of the time and may stop and reoccur at the same speed. Really no vibration anywhere else. The thump quits when going around long sweeping bends to the right and to a lesser degree when going around bends to the left. The thump is very rhythmic and can become fairly violent at times. I put on new tires to no avail. I also replaced the shocks with new KYBs, again with no change. It exhibits the same problem whether in 2wd, 4wd or Auto. I'm thinking that it's a CV joint, but I'm not sure as descriptions I've found on the forum describe different symptomns. None of the boots are torn. Any advice would be appreciated. If it is a CV joint, how do I determine which one it is? How difficult/expensive are they to replace?

 

Thanks,

David Gore

Kearney, MO

[Genuinefine409]

I had a thump that felt like it was right under my seat at times, couldn't figure it out until one day i crawled under my truck and grabbed the transfer case to pull myself under more and it moved, the mount to the crossmember was loose. I tightened the two bolts up and no more thump.

[dgore64]

Thanks for the input. I'll check that out tonight. I didn't look at the transfer case when I was under it last weekend.

 

 

I had a thump that felt like it was right under my seat at times, couldn't figure it out until one day i crawled under my truck and grabbed the transfer case to pull myself under more and it moved, the mount to the crossmember was loose. I tightened the two bolts up and no more thump.

[Wingnut]

Last time I had a "thumping" floorboard...After many days/weeks of troubleshooting and scratching my head over it...It turned out that my seat was loose.