Still driveline vibration... help!!

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I chased a vibration that turned out to be engine mounts, bolts were tight, several mechanics checked them, but the rubbers were wore out enough that it caused a vibration like u describe.

 

Something else to check, dro the driveline and lay it on the clean, level floor. Set it on the caps that have the two bolts in them. Make sure the ujoints are not out of phase. They should be right in line with one another. There should be no rocking back and forth with it on level ground. The only way this would happen is if someone cut it and rewelded the yoke...which we have a few...or if it was possible to put the slip yoke in off by a tooth or something. We had one that I just got finished recutting and rewelding in a W9 because it was out of phase after a tranny change.

Do you balance your tires?? Do you have wheel balancers on any of them?? They have been known to get stuck on one side....this is seldom but and I've never seen it on ours...but I have read it happening.

Check your brake drums....it is possible on some configurations I've seen to be able to mount a wheel and the drum not be centered on the hub and will cause a vibration also.

Just some thoughts.

 

If it started immediately after the power divider was rebuilt, then I'd suspect an error in workmanship. Something's probably not shimmed properly.

 

Check your driveshaft real close all the way around all along the length for any signs a balance weight has fallen or broken off. It may just be out of balance now.

 

I have the same problem on my 2006 Pete 387. I did a lot and spend a lot of $ ... and nothing. Changed all u-joints, new clutch, pilot bearing on flywheel, input shaft on transmission (bought full kit), central bearing, changed all tires(steer and drive) with balance, checked air ride height. One weird thing that vibration goes away for a little bit when my truck worm up(around 5-10 miles driving). Huge vibration that shaking my truck starts in the morning after night stop (around 45-65mph in the moment of accelaration, when im living the gas pedal vibration goes away) . I checked the engine mount and i find that rubber has some sign of wearing but nothing bad....i have no idea what to do.... I cant drive up hill, i got a filling that pretty soon i will lost some part from my truck. Thanks for any advice and help!

 

Might be in the engine, failed vibration dampener possibly.

 

I feel your pain, I went through this. I can only speak to my situation and I had my engine mounts checked several times and mechanics told me they were ok, in the end they were the cause. Sure hope u figure it out.

 

Again for this week I spend a lot of time and $..... and again this vibration ((
I changed dumper+pitsburg power dumper balancer, changed front engine mount, take of all drive shaft......get fixed all movements, balanced ( all new u joints), new youke on output shaft of transmission., took off rear differential....checked.....every part of it was like brand new, so i take it back. I talk to Peterbilt people about rear engine mouts....and they told me it not possible that this mounts did that ####. I cheked them by myself and they are still in good conditions ........ really need help with this BS....i have no idea what i have to change again. thanks for advice