steering wheel shake shimmy

[jcb100]

I posted same concern a few weeks ago and several said my steering wheel shake was tire imbalance. Since then I have put on new tires, had road force balance done by 2 different shops and front end alignment and still have shimmy in wheel? Shimmy seems to depend on road surface and speed as it is not present at 55... but at 65 and over you feel it. If you stop the car during shimmy, then start back the shimmy will sometime stop??? Also, On older roads where pavement is smoother, very little shimmy in wheel, yet on new roads; especially concrete expressways, shimmy is worse. One guy said the steering damper in the pwr. steering assist unit is bad> never heard of this? Is there a way to adjust the steering assist unit?? One guy said it;s just the GFORCE tires "feeling" the road. The car had no problems for the first 15k miles and problem started then. Anybody got a clue? Of course all 3 of my local Merc dealers say nothing is wrong! They don't drive 1,000 miles a week like I do... so I know what the car does and the shimmy is wrong. already wearing inside track of new tires. help!!!!

[Krytin]

You didn't say how many miles on the tires and they are already worn on the inside edges - assume they don't have to many miles and considering the rest of your symptoms - you still have a problem. I've got 26K+ miles on my '03 300A w/original front tires and they have wear on both inside & outside edges - more inside than out. I don't have any vibration or shimmy. Either all or some of the work you've had done on the car was done wrong - or you have a worn component in the front end that nobody has picked up on yet.
Just to look in a different direction - I once had a problem in the winter with snow melting & refreezing on the rim behind the spokes on a rear tire acting like a big wheel weight. This caused a vibration that could be felt in the whole car - including the steering wheel. Have you checked the rear tires for balance? Any rear end linkage/shock damage?
Good luck! I hope you get it fixed!

[merc406]

Sounds like a bad rack, also check tie rod ends, but I'm sure they have.

[jcb100]

Thanks, 25 k on car; 4k on new tires. yes rear tires were balanced as well. Have not considered a suspension part issue you suggest...certainly hope I don't have to go there, but will tyr that route. Thanks for the input!
You didn't say how many miles on the tires and they are already worn on the inside edges - assume they don't have to many miles and considering the rest of your symptoms - you still have a problem. I've got 26K+ miles on my '03 300A w/original front tires and they have wear on both inside & outside edges - more inside than out. I don't have any vibration or shimmy. Either all or some of the work you've had done on the car was done wrong - or you have a worn component in the front end that nobody has picked up on yet.
Just to look in a different direction - I once had a problem in the winter with snow melting & refreezing on the rim behind the spokes on a rear tire acting like a big wheel weight. This caused a vibration that could be felt in the whole car - including the steering wheel. Have you checked the rear tires for balance? Any rear end linkage/shock damage?
Good luck! I hope you get it fixed!

[merc406]

Thanks, 25 k on car; 4k on new tires. yes rear tires were balanced as well. Have not considered a suspension part issue you suggest...certainly hope I don't have to go there, but will tyr that route. Thanks for the input!

Take it to your dealer and tell him you want it fixed now not later!!

[Thomas C Potter]

A couple more wild ideas - is there another MM near you that would be kind enough to try his front tires; what was the toe-in dimension, sometimes tweaking the toe can change things slightly. I assume when you say 'road force', you truly mean road force not just reg balance.

[merc406]

Also check lug nut torque, may have wourped rotors.

[Bad Boy Merc]

MercMan

In July 02 when I got my new MM it had a constant pull to the right and a constant steering wheel tremble, especially at speeds above 56 MPH. It took the dealer three days and a few calls to the factory to get the streering alignment right to correct the pulling problem. They also balanced the wheels. I took the car immediately on a trip to the midwest and the tremble was still there. Since the car was due its second oil change when I got there, I took it to a dealer in Nebraska for the oil change and again reported the steering wheel tremble. They balanced all four wheels again and it improved the condition slightly but the tremble is still there. I suspect that the left front tire may be out-around based upon the fact that the mechanic swapped the front and rear tires then found out that they were different sizes. He told me that the left rear tire balanced out better than the left front when he swapped the tire back to the original positions. I have not taken it back to the dealer but intend to in the near future, while the tires are still like new (6400 miles). The shake comes and goes (gets better and worse) depending on the road surface and I get the shake at various speeds. I also wonder if it is not the rack thats at fault.

[TripleTransAm]

I am beginning to think it is steering pump related.

[cyled]

I have had the same thing, however I notice at 65+. It seems to be more noticeable after I have been driving for awhile. If I start to apply the brakes.. (not a panic stop) the wheel really shakes. I am wondering if it is not a warped rotor. I have the car in for 4 new tires, alignment and oil change. I will get it back on Wednesday. Should know by Thursday.

[cyled]

Got my car back last night from the dealership (4 new tires, alignment and oil change). Had them check the shimmy. They ended up turning the front rotors, which under warranty they are "suppose to do". The next step would be to replace the rotors.
I drove about 55 miles this morning and the shimmy is gone. Nice and smooth like new. My car has 32,000 miles on it.

[jcb100]

Yes Raod force at 2 different shops. No other MM I know of but maybe the dealer would do this...good idea thanks!
A couple more wild ideas - is there another MM near you that would be kind enough to try his front tires; what was the toe-in dimension, sometimes tweaking the toe can change things slightly. I assume when you say 'road force', you truly mean road force not just reg balance.

[jcb100]

Thanks, yes the way you describe the intermittent tremble is exactly like I experience. I am thinking of putting some 16" rims/tires on front from a crown vic just for a test and see if problem goes away...tyring to determine if it's tire issue or not.
MercMan

In July 02 when I got my new MM it had a constant pull to the right and a constant steering wheel tremble, especially at speeds above 56 MPH. It took the dealer three days and a few calls to the factory to get the streering alignment right to correct the pulling problem. They also balanced the wheels. I took the car immediately on a trip to the midwest and the tremble was still there. Since the car was due its second oil change when I got there, I took it to a dealer in Nebraska for the oil change and again reported the steering wheel tremble. They balanced all four wheels again and it improved the condition slightly but the tremble is still there. I suspect that the left front tire may be out-around based upon the fact that the mechanic swapped the front and rear tires then found out that they were different sizes. He told me that the left rear tire balanced out better than the left front when he swapped the tire back to the original positions. I have not taken it back to the dealer but intend to in the near future, while the tires are still like new (6400 miles). The shake comes and goes (gets better and worse) depending on the road surface and I get the shake at various speeds. I also wonder if it is not the rack thats at fault.

[jcb100]

Triple...tell me your theroy on why you think it could be the sterring pump? Is there some type of damper inthe sterring pump that mught be going bad and letting something come thru to the steering wheel..please expound on your theory
I am beginning to think it is steering pump related.

[Bradley G]

I have the same intermittant shimmy . first noticed it at 2000mi has 3000 now had the tires balanced yesterday( all four) drove home hit 80 mph to be sure it was fixed. seemed ok , but tonight on my way home on wet pavement over 62 started again:bigcry: I hate when that happens, I'm guessing tires. That was our service mgrs. first response when I brought it up several weeks ago. Probably because I said I notice it more when I first start driving . heck I only have afour mile commute to work!!

[Logan]

I'm taking mine in on Monday for the exact same problem... Me, I think it's the rack personally...

[SergntMac]

I'm taking mine in on Monday for the exact same problem... Me, I think it's the rack personally...
Ditto...After changing tires, balancing, alingment (both OEM and Kenny Brown's settings), and new shocks, the shimmy remains 70-75 MPH.

[TripleTransAm]

Triple...tell me your theroy on why you think it could be the sterring pump? Is there some type of damper inthe sterring pump that mught be going bad and letting something come thru to the steering wheel..please expound on your theory


Process of elimination...

Balancing problems usually come in at a certain speed, usually fairly high and usually circa 55 mph or slightly higher. This is when the imbalance sets up a resonance within the whole car as a system... you've got weights distributed at various places, with various 'springy' connections (tire sidewall 'squish', suspension springs, bushing tolerances, etc.), and several damping items (shock absorbers, soft bushings,...). One of my engineering courses in University involved modelling physical systems like this, using electrical components (weight/mass = capacitance, springs = inductance, damping = resistance). You can work out the resulting big-azz equations to determine how your overall system will behave under different excitations (harsh impact, simple displacement, varying inputs, etc...).

That being said, it's rare (not impossible) to have similar reactions like this shimmy at more than one range of speeds.

What's even MORE disturbing is that I have felt something like this shimmy through my steering wheel at speeds as low 25-35 mph... not as noticeable as what I feel at 60 mph, but enough to say "Hey, I swear that vibration is similar to what I feel at higher speeds!". Also, at speed, I can somewhat control the intensity of the shimmy by nudging the wheel against the steering resistance... it either becomes more noticeable or sometimes completely disappears.

Now, do keep in mind that this 'shimmy' I get is not the type that is liable to get Marge Simpson's hairdo to come crashing about her. It's a subtle something... slightly noticeable through the steering, slight enough to have me wondering if it isn't just the road surface that is irregular (it sometimes is). But I know some roads like the back of my hand, and at those points I am sure it's something in my car, not the road.

I gotta add that my '98 WS6 seems more apt to react adversely to high frequency irregular pavement in a similar manner (ie. I start wondering if my balance is off, or my tires flat-spotted). The common item here is a Rack-and-pinion steering system. Say what you want, but I've always liked the feel of a recirculating ball type (I have this on my GTA and '78 T/A, and had it on my Parisienne and ever other American car I've ever driven).

But I do think there is something up with the MM's power steering system... it's the only car I've ever experienced that low speed *distant* shimmy.

(one more thing... the low speed thing I barely feel, is at the SAME frequency as what I feel at highway speeds... another giveaway that it might not be wheel-related).

(yet another thing... my MM's steering system is, in my opinion, noisy. At speed, if I nudge the wheel left or right, I can hear the low hiss of the system under load. Starting from a complete stop while turning, it's downright hellacious raspy... I used to think my diff was faulty!).

[frdwrnch]

I think what we are experiencing is in fact tire runout/balance issues. The rack and pinion system is more sensitive to these issues than the recirculating ball steering system due to less mass and less component connections. The G-force tires will develope a "flat spot memory" when sitting overnight and may require up to ten miles of driving at highway speed to round them out. The Hunter GSP9700 wheel balancer w/road force measurement is a great tool to sort out these type of issues BUT it can only pick up radial runout (up and down). Lateral runout (side to side) will still cause the steering nibble and Hunter is just releasing a new machine that will help diagnose these issues. A TIRE CAN BALANCE OUT PERFECTLY BUT STILL VIBRATE DUE TO RUNOUT. A skilled technician can watch the tire on the balancer and usually tell if runout is excessive but too many techs put the tire on the balancer and walk away, returning to pound on the weights where the machine tells him to. These vibrations set up frequencies which are measured in cycles. Cycles run in phases so it is not unusual to feel the shimmy in two different speed ranges as the vibrations go in and out of phase. I recommend using a qualified shop with a tech that's experienced w/tire issues using a balancer capable of measuring road force. Try to have this work done after a little "at speed" cruising to round out the tires before balancing. May have to index the tire on the rim to minimize radial runout and the perform a dynamic balance where weights are applied to the inside and outside of the rim (behind the spokes on the MM). In extreme cases I've had to have the tires shaved by a specialist to eliminate radial runout. Bottom line is some tires are better than others and these cars are very sensitive to runout and balance.

[TAF]

I feel Russell is correct ^^^.


I just had mine re-done yesterday at Butler Tire www.butlertire.com (http://www.butlertire.com) with their high-speed (130 MPH) on-car equipment. As well...they used the Hunter, Road-Forced balancing machines with each of the fronts off the car. My problem had been trying to be "aesthetically pleasing" keeping the weights out of site/behind the spokes. I was even willing before to accomodate some "shimmy" as long as my wheels looked "clean" with no weights. To heck with that...I wanted them balanced to the inth-degree. I have that now.

[frdwrnch]

Todd, did you have trouble with the stick on weights hitting the Baer brake calipers? I had to stick the weights on the back of the spokes due to this and it took me two times to get it right.

[TAF]

Todd, did you have trouble with the stick on weights hitting the Baer brake calipers? I had to stick the weights on the back of the spokes due to this and it took me two times to get it right.
Actually...the guy was GREAT. We used the lowest profile weights that they had...then he grinded off the tops of even those to make sure they cleared the calipers. Then back to the machine to see if there were any adjustments needed with the weights due to the grinding. I told him I wanted them "spot-on" and he worked back/forth several times. And she is steady as could be, now.:up:

[frdwrnch]

Cool! Sounds like you found somebody w/ability and initiative which is the key to addressing these types of concerns.

[Donny Carlson]

Actually...the guy was GREAT. We used the lowest profile weights that they had...then he grinded off the tops of even those to make sure they cleared the calipers. Then back to the machine to see if there were any adjustments needed with the weights due to the grinding. I told him I wanted them "spot-on" and he worked back/forth several times. And she is steady as could be, now.:up:
Which Butler Tire do you take your car to?

[Bradley G]

Yeah!! What Triple T/T said,"I get the same Thing, notice it more under hard accel." I'm still trying to figure best way to duplicate this, so I can get SM to help me rectify this issue.":baaa:

[Bradley G]

I think what we are experiencing is in fact tire runout/balance issues. The rack and pinion system is more sensitive to these issues than the recirculating ball steering system due to less mass and less component connections. The G-force tires will develope a "flat spot memory" when sitting overnight and may require up to ten miles of driving at highway speed to round them out. The Hunter GSP9700 wheel balancer w/road force measurement is a great tool to sort out these type of issues BUT it can only pick up radial runout (up and down). Lateral runout (side to side) will still cause the steering nibble and Hunter is just releasing a new machine that will help diagnose these issues. A TIRE CAN BALANCE OUT PERFECTLY BUT STILL VIBRATE DUE TO RUNOUT. A skilled technician can watch the tire on the balancer and usually tell if runout is excessive but too many techs put the tire on the balancer and walk away, returning to pound on the weights where the machine tells him to. These vibrations set up frequencies which are measured in cycles. Cycles run in phases so it is not unusual to feel the shimmy in two different speed ranges as the vibrations go in and out of phase. I recommend using a qualified shop with a tech that's experienced w/tire issues using a balancer capable of measuring road force. Try to have this work done after a little "at speed" cruising to round out the tires before balancing. May have to index the tire on the rim to minimize radial runout and the perform a dynamic balance where weights are applied to the inside and outside of the rim (behind the spokes on the MM). In extreme cases I've had to have the tires shaved by a specialist to eliminate radial runout. Bottom line is some tires are better than others and these cars are very sensitive to runout and balance.If my wheel shake is due to the runout ,and goes away after they warmup 10mi or so .this can still be fixed by shaving?:help:

[frdwrnch]

If the shimmy goes away after ten minutes of driving then this is a normal characteristic of the tire and no repair is necessary. Basicaly the tire flat spots from sitting overnight and then the heat and pressure increase from driving round it back out.

[Bradley G]

If the shimmy goes away after ten minutes of driving then this is a normal characteristic of the tire and no repair is necessary. Basicaly the tire flat spots from sitting overnight and then the heat and pressure increase from driving round it back out.Had a chance to drive the car more yesterday wheel shake develops running consistanly over bumpy road conditions:cry:

[merc406]

Had a chance to drive the car more yesterday wheel shake develops running consistanly over bumpy road conditions:cry:



Doesn't surprize me none. :lol:

[cyled]

I am going on almost two weeks after having mine into Ford. I believe it was a combination of tire and rotor. Some of you stated that you have had tires rebalanced and/or alignments and still have it. I did as well. It wasn't until the turned the rotors did mine go away.

Mine was really noticeable when cruising around the 70 mph and really showed up if I got on the brakes. Not a panic stop, but one where you are have came up on a slower car and need to shave some speed off quickly. That is what made me have them check the rotors. Everything is nice and smooth for me now, clear up and over.... :nono: well let's just say more then 70 mph... a lot more.... ;)

[TripleTransAm]

I noticed this morning that I get a small shimmy through the steering wheel at idle with the brakes held. It seems to shimmy a slight amount more when turning left than right. I'm still thinking my pump is at fault here.

[Logan]

FYI, I ended up getting my tires rebalanced on a Road-Force Balancing machine. The shimmy is completely gone now.

[Krytin]

That sounds like good news as mine just started doing this shimmy thing - it starts anywhere from 65 to 75 mph. Not real bad - just enough to be annoying! It also might be time for new front tires as the originals are @ 26k now - changed the rears @ 21k.

I think I might be having a problem w/ the rear. Anyone know how much end play there should be on the axel hub? I just replaced rotors & pads all around and noticed considerable end play on both hubs - no radial movement but the hubs slide in & out almost 1/8" total travel! All my experience is on 9" rears and they don't do this!

[Bradley G]

I posted same concern a few weeks ago and several said my steering wheel shake was tire imbalance. Since then I have put on new tires, had road force balance done by 2 different shops and front end alignment and still have shimmy in wheel? Shimmy seems to depend on road surface and speed as it is not present at 55... but at 65 and over you feel it. If you stop the car during shimmy, then start back the shimmy will sometime stop??? Also, On older roads where pavement is smoother, very little shimmy in wheel, yet on new roads; especially concrete expressways, shimmy is worse. One guy said the steering damper in the pwr. steering assist unit is bad> never heard of this? Is there a way to adjust the steering assist unit?? One guy said it;s just the GFORCE tires "feeling" the road. The car had no problems for the first 15k miles and problem started then. Anybody got a clue? Of course all 3 of my local Merc dealers say nothing is wrong! They don't drive 1,000 miles a week like I do... so I know what the car does and the shimmy is wrong. already wearing inside track of new tires. help!!!!THERE IS A TSB FACTORY CALLS IT A "NIBBLE" I LEFT IT AT WORK . If I knew how to start a thread I would do so . SM where I work suggested I drive a new one to compare. The symptom was caused by body mounts too tight.

[jrzygrl]

Son of a gun...at 15,000 I just started to notice this exact same thing. Thought it was just the car feeling the road more, just didn't know why? Always at 65+ (which is most of the time for me)..more noticeable since we just rotated the tires from side to side. Inside tire wear very heavy on the fronts. So, off to the dealer I guess..

[Bad Boy Merc]

THERE IS A TSB FACTORY CALLS IT A "NIBBLE" I LEFT IT AT WORK . If I knew how to start a thread I would do so . SM where I work suggested I drive a new one to compare. The symptom was caused by body mounts too tight.

Can you post the TSB so we can enlighten our service managers?

Thanks,
Bob

[Bradley G]

I will try to remember to bring it back from work. The two fixes were check body mounts too tight . the other is what logan posted "road force balance " tsb claimed this is more sensitive than electrostatic type wheel balance .

[jcb100]

Iwould really like to see the bulletin too... I started this thread a few weeks ago and it seems more and more MM owners are now seeing the same thing and jumping in as this is a real problem. The problem does not seem to get worse, just hangs on and makes highway cruising annoying with that stupid little shake in the wheel. In short, I have been through all the fixes listed by everybody: 1) Front end re-align; 2) new tires (even tried Michelin tires off of a BMW X5 and the shimmy was still there).. just put new BFG's on with road force balance and yep, same shimmy; 3) Not the flat spot problem either as I have same shimmy when tires are good and warm after cruising hwy. speeds for well over an hour. SO, if it's something to do with body mounts too tight we all need to know! Please pass along any data you have here Bradley, Thanks MercMan4life!
I will try to remember to bring it back from work. The two fixes were check body mounts too tight . the other is what logan posted "road force balance " tsb claimed this is more sensitive than electrostatic type wheel balance .

[Krytin]

You know, I feel the vibration in the floor and the seat of the pants. The front end isn't pulling or doing anything else wrong except the mild vibration. I wonder if it could be coming from the rear or some part of the drivetrain?

[Bradley G]

couldn't find TSB at work will look it up at work and try to post this "wheel shake" Ford calls a "nibble" a technician looked for me Sat. while at work he claimed he could only see two mounts an he claimed there are eight mounts total. the two he could see looked OK. he claimed the others would have to be checked taking body off chassis. He didn't know the MM was full frame . I guess I'm still checking into this deeper. Did ford pay for Road Force balance under warranty? I noticed I have about 9 oz. wheel weights on one of the rear wheels. some ones thread I read this is excess to be able to road force balance wheel tire combo.