Harmonic vibration

[burt ragio]

I like my car with the few mods I've done but the harmonic vibration I get most noticable at 2000 rpm is destroying my passion toward my ride. The vibration I'am quiet sure goes away above & below 2000rpm. I have talked with drive shaft shops we members have worked with. Two shops said I'll sell you a drive shaft but I don't think thats the problem. I have rotated the drive shaft & it's still present. U joints tail shaft rear end yoke bearing all inspected & ok. I'am starting to think it my be the axles ? I had the rear end apart at a local Lincoln Mercury dealer just a few hunderd miles ago to have my pinion depth reset. The whine was becoming more pronounced due to the nut loosening backing out. I'am lost for answers & could use some help. I don't want to buy parts not needed to chase this problem by process of elimination. Help.

[MM03MOK]

Morning, Kurt. Maybe Bob could take it for a ride and give it an additional listen and feel next weekend. There was a rear axle TSB but only for certain 2003's, I believe.

[burt ragio]

Thanks that would be great. Any time or day that works for Bob works for me. I will send my cell #Thanks again.

[Blackened300a]

You try putting the car in park and raising the idle slowly to the point you start to feel the vibration? I noticed it at idle after I did the TC swap.

[frdwrnch]

As previously described, you need to isolate an engine vibration from a driveline vibration by running up the engine while parked. If the vibration is still there I would suspect pulleys, balancer of torque converter/flywheel issue. If it occurs only while driving, see if it is present on accelleration, deceleration, or both. Ring gear runout could be a problem here. Also, if your rear end has been set up for a while it has established a distinct wear pattern. Setting it up again results in the teeth of the gears riding in a different area which could also cause the issue. Good Luck!

[justbob]

Have you done any exhaust mods at all? I get some vibrations at that same RPM but they only came after i had exhaust work done.

[burt ragio]

Frdwrnch the vibration was present from day one with 20 miles on the odometer.
Justbob no exaust mods to date. SW headers in storage awaiting future install.Knowing that the vibration seams to go away after 2000 RPM
maybe it's the exhaust system ?

[bigjon]

personally, i would take the driveshaft out and have it balanced. it is cheap to have that done. you might be surprised that it is fixed after that.

[burt ragio]

I might just end up having the drive shaft rebalanced as a last ditch fix. But if it was out of balance the harmonic vibration would get worse as it rotates faster with increased RPMs.

[justbob]

Maybe yours was built on a Friday and they forgot the muffler weight/dampener. Have you revved it up in park yet to isolate the problem?

[RF Overlord]

Kurt, I'd be happy to give a "second opinion"...I am flexible as to when and where...any day/time except tomorrow (Monday). I am regularly in Orleans if that helps you, otherwise I'll meet you wherever you like between Orleans and Falmouth.