Excessive steering vibration between 60-90 mph
05-25-2003, 01:56 PM
#1
Instructor
Thread Starter
Excessive steering vibration between 60-90 mph
Hello everyone.I have rebuilt control arms, all new rubber bushes on sway bars,rebuilt steering rack,new turbo tie-rods, new rubber in front of control arms and finally new tyres.
I had my tyres balanced by Pirelli twice and they claim that the vibration is not caused by the tyres, but something mechanical.
Mechanical parts and rubbers parts all new.My P orsche especialists cant find any faults, apart from the car needing a complete wheel alighment. Any one out there with any ideas?
Thanking you in advance.
I had my tyres balanced by Pirelli twice and they claim that the vibration is not caused by the tyres, but something mechanical.
Mechanical parts and rubbers parts all new.My P orsche especialists cant find any faults, apart from the car needing a complete wheel alighment. Any one out there with any ideas?
Thanking you in advance.
05-25-2003, 03:38 PM
#2
Addict
Rennlist Member
Rennlist Member
Join Date: Nov 2002
Location: Parker,CO
Posts: 826
Likes: 0
Received 0 Likes
on
0 Posts
I would get the wheel alignment for sure, and also check your brake rotors they could be warped and cause some vibration, and if you have hit some pot holes or something your wheel could be out of round and you may not be able to tell by just looking at it.
05-26-2003, 02:54 AM
#4
Instructor
Thread Starter
Ok, I have new tyres and fresh skimmed brake rotors. I will let them do my alignment again, since their machine packed up at the final stage, and then swap the wheels and tyres with diferent ones. Lest see what happens. Oh, I have new wheel bearings in there too.
05-26-2003, 03:30 AM
#5
Nordschleife Master
MOTOR MOUNTS! Those are a cause that few people actually think about. How do I know? I thought I was getting carpel tunnel syndrome, then we realized it was the damned motor mounts!
Check 'em out!
- Julie
Check 'em out!
- Julie
05-26-2003, 09:17 AM
#7
Rennlist Member
This may be a steering-rack related problem. I know the universal joint in the manual racks tends to wear and need replacing or tightening when possible. Not sure about the power racks. Has yours been replaced/rebuilt?
Trending Topics
05-26-2003, 09:22 AM
#8
Drifting
Join Date: Jul 2002
Location: Espoo, Finland
Posts: 2,668
Likes: 0
Received 0 Likes
on
0 Posts
Are you using Porsche wheels or something else? We discovered that some aftermarket wheels have a too large center hole (whatever the official term is) to fit tight on the hubs... and thus even though you tighten it with the five wheel bolts, it's not always 100% centered and can cause vibrations. Cured by removing the wheel and putting it back, just a touch of luck there 
Also if nothing else helps, I've heard that torquing the wheel bolts to exactly same values (whatever those were) might work. Worth a shot if you've got a good torque wrench!
Also if nothing else helps, I've heard that torquing the wheel bolts to exactly same values (whatever those were) might work. Worth a shot if you've got a good torque wrench!
05-26-2003, 09:26 AM
#9
Rennlist Member
Sami, "coupe" has what appears to be a beautiful set of polished factory fuchs on his '96 951. Good information, though! Not that I'm entertaining the thought of fitting aftermarket wheels... <img border="0" title="" alt="[Wink]" src="wink.gif" />
05-26-2003, 11:31 AM
#10
Instructor
Thread Starter
Luis, the steering is a rebuilt unit supplied by Zims in Texas.
Sami951, my wheels are ****s, I think they may have come of a 911, I dont know for sure. The only items that I still have to look into are: Shocks, springs and the Steering shaft that couples the steering wheel to the Power steering rack.
My Porsche guru, got his alignment machine fixed today, and sometime next week, I'll drop off the car again and he will re-do the alignment and fit in some boxer wheels in front and then see what happens.
I drove the car today, and the pulls to the right, and the steering wheel shakes violently from 60 mph to 90.
Sami951, my wheels are ****s, I think they may have come of a 911, I dont know for sure. The only items that I still have to look into are: Shocks, springs and the Steering shaft that couples the steering wheel to the Power steering rack.
My Porsche guru, got his alignment machine fixed today, and sometime next week, I'll drop off the car again and he will re-do the alignment and fit in some boxer wheels in front and then see what happens.
I drove the car today, and the pulls to the right, and the steering wheel shakes violently from 60 mph to 90.
05-26-2003, 05:04 PM
#15
Instructor
Join Date: Mar 2002
Location: Inland Empire, CA
Posts: 198
Likes: 0
Received 0 Likes
on
0 Posts
I have the same problem, mine start vibrating at 85mph - but I don't have new tires and my brake rotors are questionable. Let us all know if you find the culprit!
Thanks.
Thanks.