Diagnosis help...steering odd
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Joined: Oct 2003
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From: Nova Scotia
.... 911's up to '89 and 928's have double cup & cone bearing sets on stub axles with thrust washers and adjusters .... 964, 993 on have sealed dual cage bearings - no adjustment.For the latter, they generally scream & groan long before there is any discernable play .....
Back to the OP issue, my limited experience focuses attention on the rear suspension when experiencing funky steering above 60+MPH .... one can usually pick out front end issues at 'in town' speeds.
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From: Manhattan
So I've had the shock changed. Aligned 3 times, found a worn something in an upper arm they replaced which was sort of dynamically changing the alignment. Tried it with two sets of tires. Tried it on full soft, full stiff, in between. More noticeable on full soft.
I still get, above 80 mph, more noticeably with little load on the suspension, i.e., straight line or a long sweeper on the freeway, or changing lanes, a little random feedback in the wheel, and the wheel seems a little slow to turn in, or that there is some play in the wheel. I took it to Lime Rock to get some data, and it turns under load ok, but on the straight it just seems light and a little wobbly in the steering.
Mechanic says he can't do anything more and wants me to play with the sway bar settings. I could see that if it was under a harder load or I didn't like how it was cornering, but that shouldn't affect straight line I wouldn't think.
Thoughts? Help...I've blown two track events, three really, on this already, and I really want to have a good one and get this cleaned up.
I still get, above 80 mph, more noticeably with little load on the suspension, i.e., straight line or a long sweeper on the freeway, or changing lanes, a little random feedback in the wheel, and the wheel seems a little slow to turn in, or that there is some play in the wheel. I took it to Lime Rock to get some data, and it turns under load ok, but on the straight it just seems light and a little wobbly in the steering.
Mechanic says he can't do anything more and wants me to play with the sway bar settings. I could see that if it was under a harder load or I didn't like how it was cornering, but that shouldn't affect straight line I wouldn't think.
Thoughts? Help...I've blown two track events, three really, on this already, and I really want to have a good one and get this cleaned up.
Drifting
Joined: Nov 2003
Posts: 2,817
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From: Alberta, Canada
It still sounds like an alignment issue. They can't find anything mechanically wrong with the car right? Tires have been ruled out. Can you post the alignment specs that shop is using ? I'm sure those who are knowledgeable on alignments can advise whether these are appropriate or not.
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From: Michigan
Have been hesitant to offer this reply because I'm sure you've covered this during the 3 alignments but I had the exact same symptoms - 'gust of wind on bridge' is a perfect description - and it was the kinematic toe "well out of whack" as the tech put it.
Burning Brakes
Joined: Oct 2003
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From: Kapiti - New Zealand
My 993 behaved similarly and so I went to another alignment specialist and problem solved. Car has driven better ever since and I believe mostly due to the kinematic toe. The 911 handling behavior is so dependent on its "setup".
Burning Brakes
Joined: Oct 2003
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From: Kapiti - New Zealand
My guy I originally used did all my cars for years and is one of the best but jst simply did not have the kinematic tool. He was confident and convincing that he could do it without but the proof was in the drive and the car still "moved" around. I found this link https://rennlist.com/forums/993-foru...ent-robin.html helpful and also understanding how the tool is used when making the decision to change alignment shops. Some people even buy the tool to let their shops use so they don't have to change shops.
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From: Manhattan
Well, fair points. I'm guessing so, but haven't asked and he is traveling. I'll confirm. Anyone know the Porsche shops in/near NYC that DO use/have the tools? I've been battling this all summer. Discussions of testing all the shocks or replacing the steering rack have popped up from time to time, but the mechanic is thankfully very hesitant to go that far.