Help Please (bad shimmy) - Toyota Nation Forum : Toyota Car and Truck Forums

dag8501 · 03-20-2010, 07:32 PM

Hi everyone, I am new to this forum and could really use some help. About 2 months ago my 08 highlander started to have a shimmy at around 40 mph and continue until 50 mph and then go away. I figured since the car still had the foctory tires with 43,000 miles on them it was time for a new set anyway. Went today and put a new set of michelins (mounted and balanced) all the way around hoped to put this problem to rest. With no success my car still has a bad shimmy from 40 to 50 mphs but only when accelerating. Cruising at 45 or decelerating will not cause the problem. Can anyone shed some light on this problem, not wanting to drop a boat load of money at the dealership. Thanks!

***TrailDust*** · 03-20-2010, 08:15 PM

to Toyota Nation!

You mentioned having the new tires mounted and balanced, but nothing about an alignment. Did you have an alignment performed on both axles?

dag8501 · 03-20-2010, 08:20 PM

I did not have an alignment done, but from my research an off alignment will not cause a vehicle to shimmy. Is this assumption wrong? Though I do thing there was some uneven wear on the front drivers side of my old tires, but nothing major. Would a front end alignment clear up a shimmy between 40 and 50 mphs? Thanks

***TrailDust*** · 03-20-2010, 08:35 PM

Quote:

Originally Posted by dag8501

I did not have an alignment done, but from my research an off alignment will not cause a vehicle to shimmy. Is this assumption wrong? Though I do thing there was some uneven wear on the front drivers side of my old tires, but nothing major. Would a front end alignment clear up a shimmy between 40 and 50 mphs? Thanks

As a rule that's true, but I've seen exceptional cases where a small shimmy has been induced. What's odd is it's happening even after the new set of tires. Maybe it's a chance situation where one of the tires is out-of-round on your new set? Also, is the same business that mounted and balanced your earlier set of tires also the same business that did the same with the newest set? Again, I've seen situations where faulty equipment and or operators were to blame with recurring problems.

nov0798 · 03-20-2010, 08:46 PM

Could be a multitude of things. Since you say it only happens on acceleration, I would suspect a possible transmission issue! Maybe a valve or something is not shifting the tranny properly? Maybe you have a bad set of clutch plates or bands in the tranny. Use the sportshift and accelerate in each gear through that range. If the problem goes away then it sounds like the tranny computer issue where the computer cant figure out if it wants gear x or gear y and is trying to send fluid to both sets. if the problem is still there, then is it in one gear and not the other? My best bet would be to go to Toyota and get them to scan the codes. it may have a code stored that doesnt throw a light. you could also check and make sure your ground connection to your battery is tight. If it is an electrical issue, then most likely its a bad ground, but that could be anywhere! As I said earlier, your best bet is to take it to Toyota and let them deal with it.

dag8501 · 03-20-2010, 09:12 PM

The tires that were originally on the car were purchased with it about 10 months ago. As far a the transmission goes I have tried it in manual mode in 3rd, 4th, and 5th gears and it all does the same thing shimmy from 40 to 50 but only under acceleration. I just don't know, but tomorrw going back to the place that installed the tires and having them look at the situation again (very doubtful any good will come of that visit).

***TrailDust*** · 03-20-2010, 10:30 PM

Quote:

Originally Posted by dag8501

The tires that were originally on the car were purchased with it about 10 months ago. As far a the transmission goes I have tried it in manual mode in 3rd, 4th, and 5th gears and it all does the same thing shimmy from 40 to 50 but only under acceleration. I just don't know, but tomorrw going back to the place that installed the tires and having them look at the situation again (very doubtful any good will come of that visit).

Well, if the shop you're talking about did any balancing work, etc., on the tires that came with your HL I'd be wary of that. Again, it could be faulty equipment or incompetent mechanics. Very peculiar to have a shimmy on two different sets of tires. Reminds me of the time I was in high school and working at a local gas station. All day long I was filling up people's tires because they were all coming in with low tires.

Next day a gentleman drove in screaming bloody murder that some idiot had filled his tires to 50 PSI.

Yes, my tire gauge was faulty. I got a new one and, guess what, very few customers had low tire pressure anymore....

dag8501 · 03-20-2010, 10:47 PM

The previous tires were factory form toyota i believe and were never rebalanced under my ownership. Any other thoughts or solutions on the problem?

konde.koma · 03-21-2010, 12:27 PM

Quote:

Originally Posted by dag8501

Hi everyone, I am new to this forum and could really use some help. About 2 months ago my 08 highlander started to have a shimmy at around 40 mph and continue until 50 mph and then go away. I figured since the car still had the foctory tires with 43,000 miles on them it was time for a new set anyway. Went today and put a new set of michelins (mounted and balanced) all the way around hoped to put this problem to rest. With no success my car still has a bad shimmy from 40 to 50 mphs but only when accelerating. Cruising at 45 or decelerating will not cause the problem. Can anyone shed some light on this problem, not wanting to drop a boat load of money at the dealership. Thanks!

The problem you are describing is more than likely caused by either the drive shaft or a control arm bushing/ball joint. Wheel imbalances get worse the faster you go. Driveline and suspension component issues occur between 40-60mph and may dissappear AND usually only happens under acceleration or cruise.

If it is in the driveshaft here are the main causes. There is a center support bearing suspended by a rubber bushing. When the bushing cracks it causes radial and axial movement of the bearing assembly which causes the driveshaft to vibrate under load. There are also rubber flex disc that aid in absorbing driveline shock upon accelerating. Those will also crack and cause the same problem. You usually notice clunking first before it ever starts to vibrate with flex discs. There are typically 2 flex disc on the car. One mates the driveshaft to the tranny and the other to the differential. You may feel the front/center or rear of the car vibrate/shimmy but usually not the steering wheel. The center support bearing mount cracked is usually the number one cause and requires a center support bearing assembly in most cases.

If you feel the shimmy in the stearing wheel it is more than likely caused by either the upper or lower control arm bushing. Every now and then the ball joint will cause it but you usually hear a clunking sound before you ever complain about the shimmy. Finally, it may but rarely be caused by 1-2 bad shock absorbers. THESE SHOCKS HAVE TO BE HORRIFICALLY BAD. It would have to be so bad that when you press down on the car and bounce it it looks like it dances before getting back to the original height due to the inability to dampen spring oscillations. The typical cause in the front end, non wheel, related shimmy are the control arm bushings for your type of steering system.

So remember if the shimmy causes the steering wheel to shake left to right, it is from the front end more than likely. If the front, center or rear of the car shakes with no affect to the steering wheel it is more than likely in the driveshaft area. Your typical mechanic with a brain should be able to figure this one out fairly easily or you may check youself if you have a lift. It is not as difficult to figure out vs trying to figure out why your car won't stop accelerating or why the brakes suck every now and then. "Guide" your mechanic to it by what I have told you and see what comes up. You just might have to guide him in an indirect way or else he might feel offended and tell you to go find it yourself since you are so smart. Tell him/her that a lot of people on the forums have had this issue and this was their fix. Hopefully you don't need to say anything because this is a real simple one.

Good luck!

Bobby