poly motor mount vibrations?

[TraceZ]

It is absolutely amazing how many problems old motor mounts can cause. As they age, the rubber dries out and shrinks. After enough time, the mount no longer insulates the engine vibrations from the chasis as it should.

When i got my V6 car it had bad motor mounts. That thing would rattle the teeth out of your skull. The entire interior resonated with rattles. After replacing the motor mounts, it is smooth as silk. I paid $35/each for them at the stealership, but I have a wholesalers license and get a pretty deep discount on all my parts. I know all the folks in the parts department by name.

Installing the mounts in the V6 car was a breeze. I didnt have to remove anything. I did them 1 at a time, jacking up the motor with a piece of wood and a floor jack. I just jacked the motor up as far as it would go and I had plenty of room to work. It was a piece of cake!

I'm glad to hear you are getting the bugs worked out of your car. That is always my goal: a bug-free car. I should be able to give the keys to my wife and she should be able to drive it cross country without any issues popping up. It irritates me when a bug pops up and requires constant babysitting.

[Craig 94 TA GT]

Tracy, good to hear that it was easy on the V6. The price you paid is really good...the cheapest I found them was at gmpartsdirect, $150+ shipped.
I'm the exact same way now...bug free car. Before, all I cared about was horsepower. But now, I want her to be able to run well, run for a long time, and have a perfect clean interior/exterior/engine bay.

I did another test of the poly mounts. Got it up to 70-75 mph, and the car was absolutely vibration free. I've never felt such a smooth ride at freeway speeds. The only drawback is idle and very low speeds...there is a slight vibration. But it's nothing to complain about...I don't even notice it unless I'm looking for it. Also, when you're starting it, the mounts are so solid that the whole car rocks one way with the starter. I'm not sure if it normally does this with good mounts, but my worn rubber ones didn't. I'm amazed that the motor mounts, tranny mount and tq arm mount are all poly, yet it's still a smooth ride.

[Joe K. 99 Zeee!!]

That's great to hear! I've heard such a variety of experiences that I'm wondering if some people are messing up someplace or maybe there's just another flaw somewhere else that the poly stuff is bringing to the surface.

[Craig 94 TA GT]

Yea, I think it definitely brings other problems to the surface if it vibrates bad. I was really expecting it to be smooth idle/very low speeds and vibrate somewhat at higher speeds. Kinda like the poly tranny mount. But it's the complete opposite.
Maybe the vibration worsens for those with slightly unbalanced steel driveshaft LT1s. Whatever the case, I'd definitely recommend them if you need the mounts replaced.