How many owners have noticed engine vibration (around 2500 rpms)?

[Triathlete]

Seems to me that if there was a balance issue that it would be worse as the RPMs increased and not specific to just the 2500 RPM area.
Is the engine running smooth otherwise?

[89Vette]

I remember someone talking about the 3.2's having balancer issues (balancer coming apart) awhile back. I'll ask Jerry for ya. I'm pretty sure the puller and balancer are one.

Thanks! (BTW: Who's Jerry?) FWIW, I've also heard of balancer issues in whole companies. Pioneer balancers have a bad rap after lots of failures from 2003-2008. Some even say it's still going on. (Don't know what "brand" Isuzu uses.)

Edit: If Jerry's a tech, could you (or I) ask him how to determine if the balancer (or mounts) are failing?

Seems to me that if there was a balance issue that it would be worse as the RPMs increased and not specific to just the 2500 RPM area.

Is the engine running smooth otherwise?

The engine runs VERY smooth below 2k rpms. There is no miss. Vibration does continue to exist above 2500 rpms but it seems slightly less pronounced. When I let off the gas, there is a slight stumble/vibration as it passes below 2k rpms. It almost feels like a miss. OTOH, maybe it could be the balancer "settling" back into a slower rythm. (Or if caused by a mount, maybe it's torque rebound contact/vibration.)

This could be described as harmonic vibration. The level is similar to a lawn motor above 2200 rpms. But I expect an automobile motor to feel smooth until redline.

[SlowPro48]

But I expect an automobile motor to feel smooth until redline.

Then don't buy a vehicle that has a 75 degree V6 with no balance shaft! The 6VE1 is always going to feel a little uncivilized...

[89Vette]

Then don't buy a vehicle that has a 75 degree V6 with no balance shaft! The 6VE1 is always going to feel a little uncivilized...

Are you sh'ing me? Motors (cranks) don't have a balance shaft. They have counterweights on the crankshaft.

Should I check my muffler bearings too?

[RamAirZ]

Are you sh'ing me? Motors (cranks) don't have a balance shaft. They have counterweights on the crankshaft.

Should I check my muffler bearings too?

Balance shafts go in the top of the engine, usually in the lifter/intake valley, here is a 4.3 V6 balance shaft:



Not all motors have/need them but they are used in some.

And yes I've seen that commercial, it's pretty funny lol

[SuperBoomTurbo]

This isn't it, but still damn funny. Trying to lighten the mood, y'all!

http://www.youtube.com/watch?v=J3FIZR8Sp6w

[89Vette]

Balance shafts go in the top of the engine, usually in the lifter/intake valley, here is a 4.3 V6 balance shaft...Not all motors have/need them but they are used in some.

Well, that's a new one on me!

What does a balance shaft "balance". I saw an exploded view of the 3.5L and the crank appears to have the tradional counterweight lobes. Why wouldn't that balance the rotating assembly?

Why build an engine with "extra" vibration if it could have been avoided with this part?