I have 30,000 miles on my 8. I replaced the stock suspension after 15,000 miles with the mazdaspeed springs/shocks. Last month I put the stock suspension back on and sold my mspeed parts, along with my racing beat sway bars (needed money). Anyway, this is a test for all the creative minds in this forum: my car handles terrible. It goes with any rut in the road, cutting hard left or right. When I hit a bump, the back end shimmies slightly. It goes all over the road, scary stuff. Brainstorm; I had it aligned, the obvious is out, now what could possibly cause such unstable characteristics? Believe me this is not typical, and I would rather not pay someone $100/hr. to find out what the hell is going on. help please, any ideas appreciated.

 

I suspect that your tires, which took on a new "wear pattern" with the MS suspension, have now got to readjust to the stock ride height again. Since the MS suspension lowers your car, and changes the camber, your tires probably wore more on the inside edges. Now they are wearing more normally. To test my theory, measure the tires at various locations across the tread. Check for even wear. Another thought is that you are just more aware of the suspension movement because it is now "softer." How many miles are on your tires? are they the originals?

 

Yes, they are the originals. Trust me, the car handles very poorly. I travel alot, and going down the interstate, the car will almost completely shift lanes following grooves in the road (pulls hard!) Same when stopping, if there is a groove present, pulls either way, left/right. What makes me beleive it is mechanical is when I first switched back to stock, the ride was really loose, then I had it aligned and it was better, but once I started getting some driving time in, I noticed that it sort of shimmies in the rear when I hit a bump (kinda of like a tail wagging, slightly) I will try to measure the tires. Anymore helpful ideas? I trust this forum more than mazda dealerships, isn't that funny!

 

UNEVEN tyre wear , have you accidentily swichted off your DSC ?

A good set of sway bars front and rear should help rear wheel hopping Richadr Paul is looking into the rear wheel hopp problem under hard driving .

cheers
michael

 

I'm not talking about wheel hop from hard accelerating (spinning tires), it'll shimmy in the rear when I hit a bump under normal speed. I don't have dsc. Uneven tire wear is on the list, wondering about settings, like is there a torque setting on the shock bolt (top of springs). Maybe sway bars put in wrong?? Also quick question; the cable that bolts to the muffler from the frame, what is it? (on back, just above driver side exhaust tip). Thanks guys.

 

I think KurtBob may have it right...

 

Did you check for loose bolts/nuts on the suspension parts? 2 alignments ago the tech left the rear toe adjustment on the back left loose. Over a period of two weeks it went from driving great to the rear being very unstable.

 

IT'S UNEVEN TIRE WEAR. Change out the tires and watch your car go back to normal.

 

Uneven tire wear makes sense, when it rains the car gets more squirly. Wayer coming across the tires differently. Thanks, it would have never occured to me that is was tire wear.

 

Ride around carefully the next couple hundred miles and it will settle in..