While accelerating and in gear 4 or 5, the car shakes when moving over 55. The steeper the hill the worse it is while going up, but even going down the hill there is a slight shaking that can be heard.

The issue is simmilar to when my 04 Montie Carlo needed motor mount and transmission mount replacements. The hydrolic mount on the passenger side of top part of the engine is not leaking fluid, so I assume it’s the transmission mount.

200,000 miles 04 R50

 

Many things can cause this, some more often than others and can be combinations of several.
With 200K miles the struts, wheel balance, worn tie rods, ball joints, all rubber bushing and worn out rack, can all be at issue. The work is not hard and easy on your wallet, if you can do it.

 

Started the bushing replacement with the dropped frame, replacing everything but the steering rack bushings and lower engine mount, because I didn’t know to look for them.

i didn’t lube the new OEM bushing on my driver side well enough and tore a chunk out while placing it onto the control arm.

I have to go to work, can I drive on this for a month until I can get a new one?

 

It depends on how big a chunk is missing. All you can do is put it together and see how it drives. If it were mine, I would see if a local parts store could get me one because taking it all apart again is a real PITA.

 

I replaced all the worn out suspension, unfortunately I grabbed sensen speedy struts. They seem fine for now, but I’m not sure I even needed them. Either way I’ll upgrade to performance coilovers next January.

OKAY

The shaky gear shifter and shaking at 55 under load is still quite present, and dropping the subframe I saw the lower motor mount is done.

I need a transmission mount, but I’d like to upgrade to a powerflex instead of OEM for price/longevity. I’ve perused the ECS website, but I can’t get a 100% confirmation on what powerflex kit I need.

i only want the powerflex kit for the transmission mount.

06/04 (June/2004) R50 manual

if you have answers I’d appreciate your help.

Thank you!

 

I'd suspect a worn drive shaft.