Daves85

I just bought this car and noticed a shake at 60 + mph.wheels and tires have been balanced and the 4 wheel alianment was just done.The tires are 275-40-17 on ZR-1 17 inch wheels..The mechanic who did the alianment says that the FUTURA is a cheap tire and that the 1985 was not designed for 40 series with 17 inch rims.?.Should the car have 50 series and 16 inch rims ? 0 to 60 it rides fine.
Thanks for any imput.


[Modified by Daves85, 6:41 AM 11/25/2001]


[Modified by Daves85, 6:42 AM 11/25/2001]

Mr Mojo

How old are the tires? They could be out af whack due to the alignment.
If they are brand new, that wouldn't be a factor.

But one of our ZO6 buddies had some tires that went bad due to his car being out of alignment, so he put new tires on, but has yet to get it aligned(I advised him to do it ASAP).

Another buddy bought some BFG blems. They were blems because they had excess rubber built up inside and no matter what, you couldn't balance them, his car did exactly what yours did.

I would suggest getting rid of those Pep Boy tires and getting some quality ones instead.

Also, make sure your lug nuts are tight.

Brian

Doesn't every '85 vibrate?

Just kidding! :D :D :D :D :D

Get a better quality tire. That should help.


[Modified by Brian, 8:41 AM 11/25/2001]

89 Bob L

How are the ball joints and tie rod ends? Many times when the ball joints are going, you will have intermittant vibration at 50-60-65 mph..

NotSlo

I don't want to sound like a broken record but here goes:

Find a tire shop with a Hunter 9700 balancer. This machine applies road force when balancing the tire and also measure rim runout. It will tell you in a flash whether your tires are good or not. If it cannot be brought into spec the machine will tell you. I had this problem with a new set of Nittos. My left front tire was simply no good.

Daves85

Hi MR Mojo
Excellant point,,the tires on the front are LESS then half way and do look beat up..2 new front tires were my thoughts also.I just heard a rumor that the 40 series tire on a 17 inch rim was TO much tire for this car.
Thx ,Dave

Daves85

hi 89 bob l,
The mechanic that did the aliagnment knows the cars history and said a lot of the parts are new but he also checked to Ball joints and tie rod ends before he did the aliagnment..He thinks its the cheap FUTURA tires or the 40/17 tires is to much tire for the front end..we will get new tires for starters.
Thx,Dave

rxbdwl

Your problem is not the 17 x 40 size. A lot of us run those on early C4s with no problem

Black85L98

I do not think it is your rims. Lots of folks have moved up to bigger rims and tires, no problem. I had a vibration in the back of my 85. Two alignments and a set of bushings did not help. Replaced two rims that were not perfect and the vibration was gone for good. If the rims look like they have hit anything hard replace the rim. It sucks to have a Vette that you have to keep below 60 or go crazy.

vader86

also check wheel bearings, DO NOT go to smaller rims, stay with the 17"s. AND GET RID OF THAT FUTURA CRAP. Mine caused me to wreck in about a millimeter of standing water. They have no wet traction, period. Get something along the line of Firestone SZ50's, much more expensive, but you get what you pay for when it comes to tires, usually.

AS84

I had the same problem in my 84....I had everything rebalanced ...new tires, and had the suspension checked. After the tires and rebalancing it did get better, but never disappeared. Hope you beat it

GRX

Did the mechanic who's trying to sell you new tires DO the alignment? Sorta' curious..... :blueangel: :reddevil

GRX

Wasn't tire vibration a standard feature on 76s???
Just kidding!! :blueangel:

BBA

Mine did that until I put new tires on it. I had a Sumitomo tires at first, even new they vibrated. Now I have Khumo's.

king off the hill

check your harmonic balancer?

mtnmanut

first off,do you feel the vibration in the steering wheel or your seat? 2nd i have 17s on my 84 no problems. had a vibration in mine,turned out to be the front driveline u joint. couldn't feel any play,driveshaft installed, but after removing the driveshaft could feel a rough spot when rocking the u joint. all other u joints felt fine,but while i'm that far i replaced them all. front rear and half shafts. i figured they were all 25 years young and couldn't hurt . smoooooooth. like every one else were giving you our experiences and cures. no warranties expressed or implied good luck vibrations can be a pita to find.

GREGGPENN

Check your ability to do a search and add appropriate responses to CURRENT threads!

GREGGPENN

This thread is going on 10yrs old!!!

MK 82

He is a slow reader.

GREGGPENN