Hey folks for the last 3 months my truck has been vibrating profusely when not in gear. Usually it vibrates at its worst when iding around 1000 RPM. But when I put it in gear the vibration all but goes away. I doesn't really vibrate while driving, just a little pulsating humm every so often. A mechanic told me he thought it could be the harmonic balancer, but I was wondering if it was the timing.

 

Has anyone seen this problem before or know what it could be?

 

If you have one of those 2 piece balancers with the rubber ring in between, the outer half may have slipped, throwing you motor out of balance. It will behave differently at different rpms, just like an unbalanced driveshaft. If you try to set your timing to it, things will likely get worse.

 

That's good to know. Luckly, a replacement isn't very expensive. I heard something about the flywheels in ford engines having balancing weights on them. Could that have anything to do with it?

 

I don't know if the 460 is externally balanced or not. I have never seen the weights come off before, and I imagine you would have heard something if that were the case.

 

Well I didn't hear anything, but you never know I guess. Oh, mine's a 351W if it matters. I like the idea of the balancer going out better than that flywheel anyway. I can fix the balancer. I wouldn't know what to do about the flywheel. Thanks a bunch SYCO.