shake

Is it only felt when sitting still and idling? Or while in motion? If in motion, do you feel it in the steering wheel, or your seat? Is it all the time, or at certain speeds?

Give us all the specifics.

 

OK. It's definitely engine related then. What are the specifics of the motor? Caterpillar, or something else? If so, 3406? A, B, E? Serial number or at the least specific series (6NZ or)?

Did this all start after the installation of the new clutch, or was all the work you mentioned done at once?

Hopefully your truck is at home/at the yard and you're not under load right now. Hopefully you also have a good engine guy you trust nearby. There are several things that can cause a vibration like this...unfortunately, none of them are any I'd want to try and run the truck with. If you do, you may not have a motor left afterwards.

 

I posted a link to your thread here: http://www.thetruckersreport.com/tr...34649-engine-shake-vibration.html#post3711320

It's the 'garage' section of this board...hopefully you can get some more answers to your questions there.

Good luck!

 

Had something similar on a 377 Pete. Mechanic said it was the trans input shaft bushing. Owner never fixed it.

 

just had a similar problem on my c15 western star. turned out to be bad clutch disks, springs not broken but the damper portion just wouldn't dampen anymore. felt like the truck was going to vibrate right off the road. i replaced all of my motor mounts, cab mounts, etc before replacing the clutch, because it felt fine in the pedal and wasn't grabby. did multiple injector tests, ran overhead adjustments, fuel pressure, balanced driveshafts, the whole nine…turned out was just a bad clutch. replaced flywheel, clutch, input shaft, and everything else in there while it was apart. problem solved. smooth as silk now.

i hope when you installed your new clutch you used an eaton clutch with the vct damper. if you used a cheap clutch, you may as well have put a bad one back in the truck!

FWIW, i had a c-12 that had a MINOR vibration when you were sitting still idling the truck, revving in neutral. had it since new. took it to cat and several dealers, all said it was normal. could not feel it while you were driving, only sitting still. truck has 350k and 20k hours on it now and still runs great.