I posted this on Facebook in the owners group but decided it might be better to post here since FB is a dumpster fire and the post will be virtually gone within days.
Recently I discovered that my 1994 starts to vibrate/shake around 90-100mph. The fastest I've ever driven the car was 130mph shortly after purchasing the car in 2016, and I recall it being perfectly stable.
I don't feel it at all in the steering wheel, just in the chassis itself, so through my foot on the dead pedal and in the seat of my pants.
The car has 105k miles, stock springs, and Bilstein shocks on the lower perch. Bilstein shocks were installed in July 2017 and have about 10,000 miles on them. Front tires were replaced around the same time, rear tires have 15,000 miles on them and were replaced late 2016. I have 5mm spacers on the rear wheels because the spring perches were very close to the tires and rubbing sometimes, I will try removing these and see if it makes a difference.
I had some work done on the car recently, the shop ended up replacing the rear driver side knuckle and upper control arm with new OEM parts. (The original parts weren't damaged or bent, but they broke the lower ball joint trying to separate it, then broke the upper ball joint trying to get the knuckle out, and they refused to wait for aftermarket options in order to get the car done faster...that was a nasty hit to my wallet and a very good lesson about why I should do everything myself.)
Also, 8 months to a year ago, I hit an invisible dip in the road at night causing the passenger side front tow point to hit the ground. I didn't think the hit was that hard, I was only going 25-30mph and the tow point isn't bent or damaged at all beyond some scrape marks on the bottom, but could this tweak the chassis enough to cause such an issue? None of the panel gaps seem off and the car didn't drive any differently afterwards.
What should I look for? I'm planning on having the tires balanced and alignment checked out, but beyond that is there anything I should check? I'm wondering if perhaps differences in the response of the new and old bushings in the rear could cause it? I had them give me the original arms back so I'm going to send them off and have the ball joints replaced and keep the new arms in my spare parts bin.
Replies to the FB post:
The bushings on the old control arms seemed just fine, very stiff and no cracking or other visible signs of wear or damage at all, but I'll jack the car up and check the others too.
I will do this as a starting point.
Not in the steering wheel at all oddly enough. Just in the chassis itself so more in the seat of my pants.
Any other input? If it doesn't end up being anything apparent I'll probably have a shop take measurements on the chassis to see if anything is tweaked.
Recently I discovered that my 1994 starts to vibrate/shake around 90-100mph. The fastest I've ever driven the car was 130mph shortly after purchasing the car in 2016, and I recall it being perfectly stable.
I don't feel it at all in the steering wheel, just in the chassis itself, so through my foot on the dead pedal and in the seat of my pants.
The car has 105k miles, stock springs, and Bilstein shocks on the lower perch. Bilstein shocks were installed in July 2017 and have about 10,000 miles on them. Front tires were replaced around the same time, rear tires have 15,000 miles on them and were replaced late 2016. I have 5mm spacers on the rear wheels because the spring perches were very close to the tires and rubbing sometimes, I will try removing these and see if it makes a difference.
I had some work done on the car recently, the shop ended up replacing the rear driver side knuckle and upper control arm with new OEM parts. (The original parts weren't damaged or bent, but they broke the lower ball joint trying to separate it, then broke the upper ball joint trying to get the knuckle out, and they refused to wait for aftermarket options in order to get the car done faster...that was a nasty hit to my wallet and a very good lesson about why I should do everything myself.)
Also, 8 months to a year ago, I hit an invisible dip in the road at night causing the passenger side front tow point to hit the ground. I didn't think the hit was that hard, I was only going 25-30mph and the tow point isn't bent or damaged at all beyond some scrape marks on the bottom, but could this tweak the chassis enough to cause such an issue? None of the panel gaps seem off and the car didn't drive any differently afterwards.
What should I look for? I'm planning on having the tires balanced and alignment checked out, but beyond that is there anything I should check? I'm wondering if perhaps differences in the response of the new and old bushings in the rear could cause it? I had them give me the original arms back so I'm going to send them off and have the ball joints replaced and keep the new arms in my spare parts bin.
Replies to the FB post:
The bushings on the old control arms seemed just fine, very stiff and no cracking or other visible signs of wear or damage at all, but I'll jack the car up and check the others too.
I will do this as a starting point.
Not in the steering wheel at all oddly enough. Just in the chassis itself so more in the seat of my pants.
Any other input? If it doesn't end up being anything apparent I'll probably have a shop take measurements on the chassis to see if anything is tweaked.
Last edited:
