tuck203

Hi
i recently had an accident - spun the rx8 180 and smashed the passenger-side rear wheel into the curb, completely destroying it and the tie bars on that side.

the guys at the repair shop have "fixed" it but i'm still not happy with it. they replaced the rear crossmember, suspension struts on both sides and the tie bars. they seem like good guys but i can not be sure they are not cutting corners in places. i am not the most car-savvy person but am trying to challenge them as much as possible. any advice from you guys would be greatly appreciated.

fyi before the incident the car was feeling great.

i have done 100 miles since getting it back and things havent really improved. there is still a higher level of road noise from the rear of the car than there used to be (is this usual with brand new tires?). when i take a left turn relatively quickly, there seems to be a brief nasty 'tire dragging' feeling on the passenger side rear. its a hard feeling to describe.

could any of this be down to the onboard computer "re-learning" things?? this is what the guys keep telling me. i fixed a stalling engine as soon as i got it back by doing the reset (20times on the brake pedal). that seems to be resolved.

they changed both suspension struts on the rear? could stiffness of these be a factor (if they are different from the previous ones?)?

i noticed there was about a 3/4 inch difference between the height of car on either side at the rear (i.e. between the top of the tire and the body arch). i challenged them on this, and they've said its within spec? they're alignment shop said it was 'good' and passes the spec...

lastly, as said in the title, the car doesn't fill me with confidence when i get to 70 80 mph. the front feels quite light and twitchy.

could they have overlooked something that might have taken a knock during the incident?


thanks for any help y'all

REDRX3RX8

OK, you say trouble after new tires? Your DSC is kicking in I think. Did you get only rear tires replaced? If so the rpm of front tires is different than the back. Move front wheels to back and see what happens. Check for any binding or scrapping in rear, but if you had all new tires I bet you'd have no trouble. Good Luck!

man, I wish I could get twitchy. I had a RX3 with stiff front and stiff rear bar. I got on black ice in winter 78 where everyone was in the ditch with regular cars but I maintained at 15 mph with massive twitchy, but got home.

I can dial down twitchy but understeer really pisses me off. You're only needing regular street drive, get some local guys to diagnose not the stealership, they won't solve anything.

Razz1

3/4" differance. It's fucked.

Get it up on a lift and measure it from the frame to the bottom of lift.

They need to loosen it up again let it settle, then tighten it up.

DarkBrew

Good advice.

Did they re-use any rear links? If so, make sure that they are totally straight. Check the sway bar. What about the axle/hub assembly?

Can you post some pictures?

Find out exactly what was replaced.

There are shop manuals on line to compare to the repair list

tuck203

the DSC kicking in makes some kind of sense. for a very brief moment, when i take a left turn at say at least 20mph, there is vibration from the passenger-side rear (could it be the traction control on that wheel only?).

they have lifted it back up (unfortunately while i wasnt around) but are adament that it is within all specs...

thanks for the swift replies

REDRX3RX8

Yeah, Like when you accelerate hard as you turn, It'll brake the rear wheel that's loose (spinning faster).

I've got a 1/2 inch rear height difference, maybe because someone added springs before it got it, and my DSC kicked in on on my right rear new Ecsta SPT's everytime I turned right with hard acceleration.

But the solution was to align the wheels because the rear camber was about -2 deg and the front was about -.5 degree. It's now -1.9 in the rear and -1.6 in the front. If shortening my rear sway bars links doesn't get me more neutral, I'll change the rear camber to -1.0. That also keeps the rears from slipping as much, kicking in DSC, or wearing twice as fast as the front.

tuck203

yep you described my situation well - it is exactly when i accelerate and turn left - thats when the vibration occurs (the DSC kicking in).

is this an error that the repair shop should fix? or is this a mazda-shop only deal??

REDRX3RX8

First easy test is take off that back wheel and rotate it to front, and that front to back. While off take a good look at or measure tread depth.

The back tires on our 8 wear about twice as fast, so by just being worn the back wheels can turn 1% faster even before they slip under acceleration.

When a tire with more tread is run on the back, it minimizes the DSC kicking in.

cjkim

if the impact was big enough to hit the crossmember, There's a good chance the knuckle went also. Suspension damage for the larger pieces sucks because you can't "visually" see the small damage. Little things like links tend to break or bend so those are pretty straightforward.

I'd take it for another alignment for a second opinion. I don't know how honest the shop is, but some shops will ask the alignment shop to pass the car because of other shoddy work.

Winning 8

wheel bearing is shot, reason is when you turn left, the car will lean to the right, which put load to the right side more, so if there is a drag or more road noise when you turn left that means the wheel bearing on the right which is passenger side is shot.
go home jack your car up and wiggle your passenger rear wheel top and bottom, and side to side to see if there is any play on the wheel.

tuck203

thanks - i jacked up both sides of the car seperately and rocked the rear wheels. i found none or very little movement. at least there was no difference between the left and right rear wheels.

since then i have also discovered that the dsc kicks in when i accelerate round a left or a right turn. it kicks in earlier for a left turn but the same effect happens - an instantaneuos vibration as the dsc takes over incorreclty. does anyone know how the dsc is controlled? - is it influenced by the front wheels?

i did only have the rear tires changed. will changing the front tires with new ones help the situation.

Lord ET

iTrader: (1)

Here's the easy test to see if it's the DSC.... Turn it off and repeat your test. Hit the DSC button to the left of the steering wheel and traction goes off. Hold it down for several seconds ..7 and stability control will be disabled. Your car will now be able to peel out and spin so be careful! Don't test this on a public street.

Winning 8

If it's a dsc issue I think you need to change all four tires, did you use same brand tires or different, even the same brand, new and old tire have different grip level, this will make your dsc go haywire..