Vibration in 2000-2500 rpm range

[Georgeb]

More like fuzzy rear view.
Is the pilot bushing something to change out if I have to change my flywheel out anyways? As in, is that a wear item?

It is a wear item but it doesn't wear very fast unless something is miss aligned or it was replaced with one of poor quality. I preferred to use a brass or bronze one as opposed to the needle bearing type. Like I said this most likely isn't the cause of your vibration but it isn't unheard of either. Basically since the vibration is present even with the clutch disengaged indicates it is something to do with the rotating assembly or the flywheel.
One other thought would be to remove the belts from the front and see if anything changes you should be able to run for a while without a water pump and with a charger on the battery if you start up when the engine is a little warm but not a full temperature.

 

[bucket]

I also prefer the bronze type bushing.

Since there has been a motor swap, there is something else that is easily checked- the balancer. It's possible it could have the wrong one, like from a 400. The outer ring should be smooth, without any notches in it. Also make sure the outer ring is still firmly attached, not loose and/or wobbling around.

 

[adamj]

I put in a brand new OE AC Delco balancer meant for the 350 (pn: 6272222). I'm sure this is the right one, it is smooth like you describe (besides the TDC knotch) and it helped a lot with vibration compared to the old worn out one.



An update on this issue:
I took the vehicle in to a shop today to have them try and diagnose it, and they said there was a chance it could be the flywheel, but the vibration was much less pronounced than what would be expected with a poor flywheel. They said it is more than likely something involved with the internal balance of the engine, and would involve some serious amount of work to reconcile (i.e. taking the engine apart and shaving off pieces of metal or something). In fact, they said they would not have noticed it if I hadn't mentioned it (not sure I believe that one) but the point they were making is that it is not bad and everything is fine.
So, I've decided to let it be for now. I think this has been an issue ever since the reman. engine was put in, because the PO was not aware of this vibration when I brought it up. So I'm chalking it up to a poorly done engine build several years ago - so I guess the engine is not the smoothest running 350 out there.

 

[bucket]

If/when you ever do the clutch again, I think it would be wise to replace the flywheel at that time. May not fix it, but it would be good news if it did.

 

[bucket]

If the vibration is that minor, have you checked the condition of the motor mounts? They tend to sag and the engine sits lower. It's actually possible for an 8" balancer rub a hole in the crossmember.

 

[adamj]

Motor mounts are good, they are brand new along with the transmission mount. The old ones were worn and had a different quality of vibration associated with them that went away after being replaced.

I would say the vibration is slightly more than minor in my opinion, and probably originated from the engine builder who didn't treat it like it was his own. The engine performs well otherwise, it has plenty of power and great torque, should last me quite some time since it only has about 40k miles (or so I'm told)

When the time comes, I'll do it up right with a new 350, clutch kit, flywheel, maybe even drop and rebuild the transmission at that point, transfer case rebuild, and I could also paint the engine bay, frame rails, and even... haha! this is what happens - I start making big plans.

 

[NOPHO84K30]

Ya my truck shakes at all speeds.