flyingfossil

at 52mph and on up my car shakes...it's not the tires..they are new and had them road forced just to be on the safe side..it's not the u joints...put a new drive shaft in..not the clutch out of balance...replaced that too..This car has 33000 miles on it. I'm wondering if a rust etched wheel bearing would cause this problem..Has anyone else had this issue??? Thanks

RotaryRocket88

iTrader: (7)

http://www.mazdatrix.com/g2.htm

A wheel bearing can cause noise and vibration. Jack the car up and try to force the wheels to rock side to side. If there is any play, that's a sign that that bearing is toast.

misterstyx69

iTrader: (142)

Bad ball joints can cause a speed vibration on the front end.

petex

check the transmission and engine mounts also.

misterstyx69

iTrader: (142)

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/images-worn-lower-strut-ball-joint-971688/
this is why I am saying Ball joint.
You can't really see it,but you can feel it.The wheel will just wonder around when it gets up to speed...and ya,I found around 50mph the car would like Jump on that corner,,,like a rabbit in the tires!
But if you slowed down it would go away.

flyingfossil

checked the ball joints and replace the front wheel bearings..still shakes..I put the car on jack stands mounted on the shock mounts to get a real geometry reading..If I get it up to 35-40 the is a very noticable shake in the body. kinda creapy laying under a car that is shakeing but there are no noticable shakes coming from any where in particular..used the stethiscope to check for odd bearing noises, none found..any suggestions?

I think I may have figured it out...I removed the rear half shafts..ran it..still shook..put a jack under the trans to releive any pressure from the mounts..ran it..still shook..put a jack under the front of the differential to agian releive any pressure on the front mount..still shook...drained the rear end grease which appears to be metal flake...but if it is the rear diff wouldn't it make a whinning noise also? most of the rear ends I see go out make plenty of noises..this one isn't//just a harmonic humm with a vibration..loose side bearings is my guess..anyone else have a simular prob or am I once again the recipient of unique problems?

it's not the rear diff internally....new mounts are ordered...if this doesn't work then I'm putting a 4x4 ranger chassis under it...not really but it's really pissing me off...