: 89 Camaro vibrating at high speed
Jan 9th, 00, 12:48 AM
I have a problem with this car vibrating at speeds around 65 - 85. It wants to smooth out about 90+. This is an annoying vibration that is not really distinct as to if it is a side-to-side vibration, or front-to-back vibration. It basically wants to shake the front dash pretty bad and you can feel it shake in the seats. There isn't any vibration in the steering wheel. It does seem to fee like the vibration is coming from the rear of the car.
I have replaced the rear-end thinking it was bent axles. I have new wheels and tires that have been computer balanced to 0, I have put new u-joints in, check the back hub weights, I have had the front end gone through with a new idler arm and alignment, etc..etc..
Nothing is working to cure this vibration. I need some insight on what else could be wrong. I have not had the driveshaft checked for balance, but it shows to not have thrown any weights or been hit in any shape or fashion.
Any and all input would be great on this matter.
1st & 2nd GENGuy
Jan 9th, 00, 03:01 AM
Have you rotated the tire to see if that makes a difference? (front to rear).
Do you think it could be in your transmision? Is it only at a certian speed or is it RPM related?
68SS ZZ4, 4sp T-10, 12 bolt, getting painted
78Z28, 330hp vortec, TH350, 10 bolt (just finished)
Jan 9th, 00, 05:05 AM
Yea,that sounds like a tough one.Like 1stn2nd gen. was thinking,if it is engine,or tranny related,RPM would have an effect on it.A friend of mine had a truck once with a mystery vibration,it turned out to be his main bearings in his engine.What happens if you get it up to vibrating speed then shift into neutral?If it goes away it's probably engine related.And this test is free!I don't know how you can accurately test to see if it is tranny related,except to swap trannies?Of coarse a last resort.Maybe pull the inspection cover off of the trans. to look for converter or flywheel damage.I don't know how much $ to balance a driveshaft,maybe cheaper to get one from a junkyard just to swap it in and see if the vibration changes?Also this is assumeing that all the work you already had done was done correctly and used good parts i.e. putting on a used bent rim? Just random thoughts,good luck.
67 RS RAGTOP # matching, 4X4 CHEVY TRUCK
[This message has been edited by 67drake (edited 01-09-2000).]
Jan 9th, 00, 05:46 AM
Take the driveshaft to a reputable driveline sop and have it balanced and have some quality spicer u-joints put in.
Questions for you:
When you changed u-joints did you make sure all the snap rings were seated properly, and did you put the snap rings on the cups that go to the rearend yoke? What brand of u-joints did you use? These may all have an effect on your driveshaft.
70 & 1/2 RS
SB406 & M20 4spd
70 Malibu 350/TH400
Gold member #103
Jan 9th, 00, 06:06 AM
It the car has a brand new engine with less than 3000 miles on it. I have done the test of putting the car in nuetral at high speeds, and it still wants to vibrate. Same way with letting off on the gas at high speeds, it still wants to vibrate.
The U-Joints were put in by a reputable mechanic shop. I did watch him do it. Everything was tip-top and done correctly. I used Spicer u-joints. All rings were set in correctly.
The tires were brand new and had been turned and have been rotated. These were brand new wheels out of the box, and like I said I had these wheels checked for trueness and roundeness. Everything checked out great.
Anymore Ideas, tranny isn't out of the question, but the thing runs so smooth and shifts great. It would be a tough call on the tranny.
With this said anymore ideas?
[This message has been edited by 89streetlegal (edited 01-09-2000).]
Jan 9th, 00, 09:33 AM
Had the same problem with my 67 Camaro drag car years ago and it turned out to be the drive shaft out of balance. Listen to Scooter and take the shaft to a driveline shop and have it trued and balanced. The newer shafts that come with the original u-joints stuck in place with plastic are especially prone to this problem. Scooter can correct me if I am wrong on this but the info came from a pretty reputable source...The factory puts the shaft and the u-joints in a jig and sets them up perfectly straight...then they inject the plastic to hold everything in place. The yokes on the shaft can be out of line a fair amount but the plastic method makes up for it. Everything is fine until the factory u-joints wear out. Now you replace them with new ones that are held centered in the yokes with snap rings. If the yoke was off center from the factory...now you have off center u-joints. Been there done that ! The original u-joints in my 85 Blazer were fine until one went bad at 90K miles. I replaced them, then I replaced them again, and again...every 8K miles or so until I took the shaft to a driveline shop and found out the yokes were off center. Had it fixed and drove another 80k miles till I sold it last year.
Hope this helps,
Advanced Automotive Machine
Jan 9th, 00, 12:58 PM
also you could check your trans. mount?? good-luck...
Jan 10th, 00, 03:36 AM
If your car does not have a Posi rear end, jack one wheel up and slip it into drive, spin the wheel up, and see if the vibration, is common on both sides or just one side.
Remember that the wheel will be turning at twice the speedometer reading when you do this, so then your vibration will at about
35-45, It will reoccur at 70 -90 as well.
Check the brake drums, has a weight been thrown from the drum? Have they been machined? or is a large chunk missing from them?
You can narrow the test down by removing the wheels and drums, does the vibration still exist? Then you want to look at the drive shaft / drive line.
let us know what you find.
Jan 10th, 00, 06:06 AM
I appreciate the feedback. I am going to do all these troubleshooting advice given to me. I will let you know what I find out after I do this.
Keep posting if you all have any more suggestions. I appreciate you alls help.
Oklahom City, OK
Jan 10th, 00, 02:39 PM
BillK is right on with the u-joint description! He just explained it better and in more detail than I did. I work in a driveline shop and do these type of things everyday. A mechanic at a regular auto shop could have done everything correctly, but unless he has access to a driveshaft balancer, he cannot fix your vibration problem by only replacing the joints.
If I was a betting man, my money would be on the driveshaft as the culprit here.
Good job, BillK
70 & 1/2 RS
SB406 & M20 4spd
70 Malibu 350/TH400
Gold member #103
Jan 10th, 00, 03:23 PM
Make it unanimous for the driveshaft. The 4th generation Camaros have a bulletin for high speed vibration, and it is the driveshaft. They can get twisted or bent relatively easy.
Jan 11th, 00, 07:40 AM
When you say twisted od bent fairly easily
are you refering to the driveshaft or the drivers , I belive there was a bulletin
on both subjects...
all kidding aside , I'll cast my vote on the Driveshaft
Jan 12th, 00, 03:55 PM
i had a bad virbration on my '69 around 4000 rpm. did it slightly in 1 and progressively got worst in 4th gear (around 95 mph. i suspected the driveshaft, but it turned out someone had put the needle bearings in backwards. had to replace the u-joint and yolk, but it fixed the problem
To see a pic of my car, click here... pages.prodigy.net/mtbmtb/rf396ss.jpg (http://pages.prodigy.net/mtbmtb/rf396ss.jpg)