Severe Tire hopping!
Thread Starter
2nd Gear Member
Joined: Mar 2006
Posts: 350
From:
RE: Severe Tire hopping!
i took the car to my buddies suspension shop again today, and we jacked up the back of the car and let the car run. The drivers tire spins straight, but the passenger doesnt. We checked the rim and axle and they are both straight and fine. He seems to think that the tire was installed on the rim wrong, or it is defective. This doesnt seem to make sence because if this were the case, wouldnt it vibrate all the time. It is weird because sometimes the car will ride smooth as can be, then others times it is a ride from hell! The shock mounts are in pretty poor shape, becasue of the air shocks that were on the car. How ever since the wheel doesnt spin straight when the car is off the ground that leads me to believe that that isnt completly the problem.
Thanks a lot
Matt
Thanks a lot
Matt
5th Gear Member
Joined: Jan 2006
Posts: 2,645
From: So-Cal
RE: Severe Tire hopping!
ORIGINAL: Soaring
Keep remembering that it only happens at a certain (25MPH) speed. If the driveshaft was out of balance, it would cause vibration at all speeds, but especially at the higher speeds, which he reports it smooths out. If the U joints were shot, it would cause vibration at all speeds.
ORIGINAL: Silver Ponys
You metion a radical stance is it possible the drive shaft angle has changed enough to cause a vibration
You metion a radical stance is it possible the drive shaft angle has changed enough to cause a vibration
this is a weird one...is it on one side?
5th Gear Member
Joined: May 2005
Posts: 2,445
From:
RE: Severe Tire hopping!
Moparmatt89,
Did you check the rear axle to make sure you do not have any toe in, and did you go back through the front suspension that you just had replaced to make sure there is nothing loose, like I suggested in another thread you started on this problem?
ebluekeys,
Make sure you have not overtightened your rear shackles, otherwise you either have too much spring or too much high speed (shock shaft speed) damping.
If your old shocks are worn out or light duty, toss them back on and see how the car reacts to bumps. If it doesn't hop, by a set of shocks with softer damping. If it still hops, find fatter friends or go to lighter springs.
Good luck,
Did you check the rear axle to make sure you do not have any toe in, and did you go back through the front suspension that you just had replaced to make sure there is nothing loose, like I suggested in another thread you started on this problem?
ebluekeys,
Make sure you have not overtightened your rear shackles, otherwise you either have too much spring or too much high speed (shock shaft speed) damping.
If your old shocks are worn out or light duty, toss them back on and see how the car reacts to bumps. If it doesn't hop, by a set of shocks with softer damping. If it still hops, find fatter friends or go to lighter springs.
Good luck,
Thread Starter
2nd Gear Member
Joined: Mar 2006
Posts: 350
From:
RE: Severe Tire hopping!
thanks for the reply Scott!
My friend i am checked the whole suspension and cant seem to find anything that would cause this sever of a hop. the only reason that i am now leaning away from the suspension being the problem for right now is because we took the wheels off and put them on a balancer. All of them spun fine exsept the passenger side rear tire, which was way off balance, and was all over the place. The tire deonst spin staright and wobbles, the rim checks out to be straight as an arrow. I am thinknig that the gas station that i had the tires put on the rims, might have messed up. If not it could be a defective tire. in which i hope i can get my money back. They are mickey thompson tires so it isnt like i bought it from some cheap tire place behind walmart. It is just weird becasue i would htink that a defective tire would casue problems at all speeds.
My friend i am checked the whole suspension and cant seem to find anything that would cause this sever of a hop. the only reason that i am now leaning away from the suspension being the problem for right now is because we took the wheels off and put them on a balancer. All of them spun fine exsept the passenger side rear tire, which was way off balance, and was all over the place. The tire deonst spin staright and wobbles, the rim checks out to be straight as an arrow. I am thinknig that the gas station that i had the tires put on the rims, might have messed up. If not it could be a defective tire. in which i hope i can get my money back. They are mickey thompson tires so it isnt like i bought it from some cheap tire place behind walmart. It is just weird becasue i would htink that a defective tire would casue problems at all speeds.
Thread Starter
2nd Gear Member
Joined: Mar 2006
Posts: 350
From:
RE: Severe Tire hopping!
oh, and i forgot to mention that my friend has owned a suspension shop for over 30 years so he knows what he is doing. I didnt want you to think that when i said friend, i was talking about someone who doesnt know anyhting about car, so he is a reliable source.
I ♥ Acer
Joined: Oct 2004
Posts: 17,565
From:
RE: Severe Tire hopping!
ORIGINAL: moparmatt89
thanks for the reply Scott!
My friend i am checked the whole suspension and cant seem to find anything that would cause this sever of a hop. the only reason that i am now leaning away from the suspension being the problem for right now is because we took the wheels off and put them on a balancer. All of them spun fine exsept the passenger side rear tire, which was way off balance, and was all over the place. The tire deonst spin staright and wobbles, the rim checks out to be straight as an arrow. I am thinknig that the gas station that i had the tires put on the rims, might have messed up. If not it could be a defective tire. in which i hope i can get my money back. They are mickey thompson tires so it isnt like i bought it from some cheap tire place behind walmart. It is just weird becasue i would htink that a defective tire would casue problems at all speeds.
thanks for the reply Scott!
My friend i am checked the whole suspension and cant seem to find anything that would cause this sever of a hop. the only reason that i am now leaning away from the suspension being the problem for right now is because we took the wheels off and put them on a balancer. All of them spun fine exsept the passenger side rear tire, which was way off balance, and was all over the place. The tire deonst spin staright and wobbles, the rim checks out to be straight as an arrow. I am thinknig that the gas station that i had the tires put on the rims, might have messed up. If not it could be a defective tire. in which i hope i can get my money back. They are mickey thompson tires so it isnt like i bought it from some cheap tire place behind walmart. It is just weird becasue i would htink that a defective tire would casue problems at all speeds.
1st Gear Member
Joined: Nov 2005
Posts: 54
From:
RE: Severe Tire hopping!
This sounds a lot like what happens when a unilug wheel is mounted off centered on the studs. It's usually pretty noticeable at low speeds and disappears at higher speeds. It's especially noticeable when slowing down and braking.
If your wheels are spinning perfectly centered when mounted on the car but the tire is not, I would think this would mimic what you would experience with an uncentered unilug tire.
Sounds like you definitely found the cause of the problem.
If your wheels are spinning perfectly centered when mounted on the car but the tire is not, I would think this would mimic what you would experience with an uncentered unilug tire.
Sounds like you definitely found the cause of the problem.
Thread Starter
2nd Gear Member
Joined: Mar 2006
Posts: 350
From:
RE: Severe Tire hopping!
Thanks for the reply KStang65!
Believe it or not that was one of the first things that we thought it was. We took off the wheels to check and see, but it turns out that they arent unilug. The wheel has a hole for each lug that fits onto each stud with no movement, its not like the cragars i have that actually do have slots for different lugs measurements. We also thought that it could be the lug nuts, because with some of these aluminum racing wheels you need the step down lugs with washers i think they are also called shanks. That turned out negative because the lugs that are on the car were made to fit the wheel perfectly, they are tappered to the design on the inside of the wheel, so once they are tightnend down there is no way they can move.
Thanks for the info!
Matt
Believe it or not that was one of the first things that we thought it was. We took off the wheels to check and see, but it turns out that they arent unilug. The wheel has a hole for each lug that fits onto each stud with no movement, its not like the cragars i have that actually do have slots for different lugs measurements. We also thought that it could be the lug nuts, because with some of these aluminum racing wheels you need the step down lugs with washers i think they are also called shanks. That turned out negative because the lugs that are on the car were made to fit the wheel perfectly, they are tappered to the design on the inside of the wheel, so once they are tightnend down there is no way they can move.
Thanks for the info!
Matt