The 2004 has been exhibiting a weird knock and I'm stumped. It goes like this - slow down to a stop, and within the last few feet of approaching a stop sign - one subtle knock. Then leaving from a stop, within the first few feet, another subtle knock. It's pretty dull. Definitely something in the front suspension. Sounds like it's coming from the front-right wheel area. I can idle/coast down the street and manufacture the sound by just braking, accelerating, braking, accelerating, etc. It's so predictable, I can do that and almost make it sound like a metronome.

The puzzling thing is that the front suspension is entirely new, other than the radius arm bushings. Ball joints, panhard rod bushings, steering rods and rod ends, front shocks, wheel bearings, CV joints, differential, sway bar links, sway bar bushings - all new within the last 5000 miles. I feel like the lateral, forward-rearward motion that causes the clunk could make the radius arm bushings suspect, right? But even still, the entire truck is only at 96K, and that seems super pre-mature for radius arm bushings to fail, yeah? I don't know.

Thoughts?

 

I think it's an age thing over a mileage thing with rubber on these trucks at this point. pop under there and check all suspension connections for cracking. check your engine mounts as well for good measure. check the watts linkage bushings too.

 

It is an age thing, you're right. Wonder if those would play into this? The knocking never occurs on bumps or anything that would cause the suspension to move up and down. It's only a fore and aft situation.

 

So this is above and beyond the usual drive line lash that occurs on these trucks?

Drive line slop is a well known feature of these vehicles. Most easily noticed by doing exactly as you describe. On and off the throttle/brakes.

 

Definitely not driveline slop. I know that sound well, haha. It's definitely coming from the right-front wheel area. Maybe it's one of the new wheel bearings? I've certainly had issues with them in the past.

 

Yep, both good places to look, watts (the watts would be moving up and down from merely stop and go driving, while braking - rear of body unloading suspension, acceleration - loading rear suspension) and motor mounts. Plus, rechecking previously done work never hurts.

 

I had a 'clunk' sound, right front. same situation with accel / decel. Was a loose caster arm at body mount. Just a hair of play, snugged up bolt and gone. rubber was fine...

 

I'm dumb - is caster arm also a radius arm?

 

Yes it is.

 

If you have a Pep Boys near you, they will check out your suspension for $20. Any time I hear a mechanical noise I can’t figure it out, I just take it to them. I make sure the master tech does the inspection.