Figured I'd post here first since I only hear this noise while towing. Tow vehicle is a 2011 Ram 3500 dually and while static, both trailer and truck are perfectly level. 82000 miles with new front ball joints. Tongue weight is no where near the limit.

When towing (especially uphill) when I hit larger expansion joints there is the initial sound of the front tires hitting the joint and then a clunk rattle coming from directly under the dash in the footwell area. Sounds like someone his hitting the firewall area with a hammer 3-4 times immediately after a bump.

Hopefully someone here has had this symptom before. Any ideas of what this might be? Body mounts? Maybe the front struts hitting a limit?

Thanks in advance!

 

Clunks like that are usually broken suspension or frame parts. It's a truck issue, not trailer. You'd get better support if you posted this in the right truck forum. It would also help to compose a signature or fill out your user CP so folks would know at a glance what your ride is. For instance, 2WD and 4WD have totally different front suspensions. Lift parts add to the problem, etc.

 

Thanks a bunch j_martin - yes definitely a truck issue but the symptoms are only there when towing and the front suspension is slightly unloaded. But the clunk is coming from so close to the firewall that I'm leaning towards something like body mounts instead...

Will also try the 4G forum.

 

That's why I want to know what you're driving. The rear pin on a front leaf spring, if worn, won't make any noise unless it's unloaded, as in hitting a bump with the front end light. Loose spring mount rivets likewise.

Would also help to know what kind of trailer you're pulling, ie bumper tow, gooseneck, bumper tow with load levelers, etc.

 

Makes sense. The trailer is a 36' bumper tow with load leveling spring bars and anti-sway. But the noise is definitely coming from the front end!

 

Check the sway bar bushings and links.

 

If also feeling the clunk in the steering wheel it could be the intermediate shaft is binding. The splines may need to be relubed.

 

Probably a loose lower shock bolt....left side.