I bought a &quot;91&quot; W250 w/CTD about a year ago. When I bought the truck I noticed that when I reached about 25mph it would develop a shimmy/vibration in the front end and then it would be gone at about 35-40mph. Then it would return at about 55mph and leave again at around 60mph. The dealer at the truck lot where I bought the truck said he thought the truck had a bent rim. Anyway I bought the truck and bought four new wheels soon after. I have since purchased two sets of tires and I still have the problem. I also tried two wheels and tires (on the front) from a friend of mines truck with no improvement. I have taken the truck to two local auto shops and the local dodge dealer. They all say the front end is solid, motor mounts are fine, drive shaft is balanced and that they believe it is in the wheels and tires. I've rotated the tires around the truck and balanced them several times without any luck. I'm looking for any ideas or suggestions as I'm about to give up.<br><br>Thanks in advance,<br>Barry<br>

 

2 wheel or 4 wheel?

 

Check the run out on the front hubs -- your wheels might run true, but if the hub isn't . . . You could also try getting your wheels balanced on the truck if you can find a shop near you set up to do it. Some times hubs can have significant alignment or balance problems.<br><br>Good luck. The hardest problems to fix are the ones that you can't find, huh?<br><br>Alec

 

Thanks Dan and Alec for your comments thus far. Alec you mentioned checking the &quot;run-out&quot; on the hubs. This is a foriegn term to me. How do I measure this or is it something that I need to have done in a shop? <br>The bearings have been checked at the local Dodge dealership and are supposed to be in good shape. I have wondered if the hub or axle could be bent - if that's possible - the dodge boy's didn't mention that but I was under the impression that they had made up thier minds that it was a bent wheel. That was before I replaced wheels and tires.<br><br>Thanks guys - keep your good opinions coming - I'm making a list of things to check.<br><br>Barry

 

I have experianced similar problems on other make 4x4s. no offence to the mechanics. but a look yourself would help. check the steering box for looseness for one. I have searched up and down to find no problems on my trucks. However the stock steering damper is something that can make a huge improvement when replaced. Im not even sure your truck came with one, its attached to the tie rod on one end and the front axle at the other, its basically a shock absorber for the steering. any 4x4 shop or most auto parts stores can get you one for about $50 or so. If you are running larger tires this will compound the problem. and if nothing else a new damper will help somewhat.
keep us posted. what tires are you running??? what size? how bad is the shimmy? thumb buster if in the spokes of the steering wheel???

 

I'm currently running Firestone Radial A/T's (LT235/35R16). These tires have an &quot;E&quot; rating which means they have a few more cords/plys in the tires. I did notice that the shimmy seems to be dampened slightly when I removed the previous tires which only had a &quot;D&quot; rating and replaced them with the heavier ply (E rated) tires.<br><br>My 91 W250 didn't come with a steering stabilizer/dampener as far as I know. That may be something that I should try - but would I be trying to &quot;band-aid&quot; the real problem - whatever that is.?? <br><br>As far as how severe the shimmy is - it's not the kind of shimmy that makes you feel like your losing total control of the vehicle but it is something that is very annoying and unsettling. It seems to be more severe at times than others. <br>I have noticed that it seems more violent when I'm towing a trailer or the truck has a load on it. It also becomes more violent when I apply the brakes when it is already in it's &quot;shimmy mode&quot;.<br><br>Thanks,<br>Barry

 

[quote author=bcb1962 link=board=9;threadid=15272;start=0#143719 date=1054267029]<br><br> <br>I have noticed that it seems more violent when I'm towing a trailer or the truck has a load on it. It also becomes more violent when I apply the brakes when it is already in it's &quot;shimmy mode&quot;.<br><br>Thanks,<br>Barry<br>[/quote]to me that would me somewhere in the braking system

 

Barry,

FWIW This is straight out of the DC factory manual

Front Wheel Shimmy

loose or worn wheel bearings
tire/wheel out of balance
uneven tire tread wear, or excessivly worn tire tread
worn tie-rod end ball studs
loose or worn susspension arm bushings (2wd)
loose or worn upper suspension arm ball studs
incorrect front wheel alignment (particularly caster)

Other items to consider

loose or worn steering shaft coupler
loose or worn steering box output shaft
Mounting plate between steering box and frame (known to devlope cracks)
loose drag link
loose or worn pitman arn
loose or worn leaf spring bushings
excessivly sagging front leaf springs
Loose front axel u-bolts
Shifted front or rear axel
Bad u-joints

You might start with a good alignment shop (preferably a 4x4 shop that is familiar with the Dana 60 axel) but if they find a problem that prevents them from perforfing the alignment have them show you what it is and rule out any other cause before having any work done. Too many shops will just change parts without really finding the problem.

 

Run-out is a bent hub. You would ideally attach a dial indicator to some non moving axle part, and let it run on the surface of the hub lange to see if the flange runs true around the spindle when it is rotated.<br><br>On further reflection, after reviewing the other posts, it is quite possible that your king pins don't have enough pre-load.<br><br>There is a tapered roller bearing in the bottom of the steering knuckle, and a spring loaded bushing in the top. This spring loaded bushing is supposed to provide enough pre-load (resistance to turning) to act as a dampener on the steering. I can't remember what the spec is, but you can measure how hard each knuckle is to turn by disconnecting the tie-rod (and drag link on the driver's side) and putting a spring scale on the arm, and seeing how many lbs it takes to pull the nuckle around. It couls be that this is too loose. The fact that it is worse with a trailer leads me to believe that this (or something similar) is the problem, NOT run out in the hub or something bent.<br><br>Alec

 

Well I know what you are talking about with your front end shimmy, as I have had it for some time. I have been trying to avoid throwing large amounts of money at it till I can figure out what is going on. If I have worn tires it will get much worse. I have put on a stabilizer shock on and it helped. In fact with new tires it does not exist. I have come to believe that it is my front springs sagging and rotating the axle. What I want to do is raise my front end back up and see where that leaves me. Check and see how much room you have between the spring and bumpstop. I only have about an inch. I cant remember but I think it should be more like two or two and a half.

 

I dont remember which pile I had that shook like your explaning but I recall it would momentarily get worse when i hit the brakes. It sounds like when you tow the tounge weight is in effect lightening the front end and causing it to get worse. I see you have been through a few sets of tires with no change, but it sounds like a tire belt problem. I finally made the dealer take back the 33x12.50x 16.5s I put on my Cheby, I had them balanced 4 times in 1k by different shops and was told every time they were way off. These were a major brand build. they put 4 new of a different brand and problem is solved............... so far??

 

Thanks for the advice thus far guys. I'm in the process of trying a few things. I've ordered a steering stabilizer and will be putting it on in the next day or two. Also, when I said that the shimmy seems to be a little worse when I'm pulling a load - that's when I'm pulling my gooseneck trailer - so the weight shouldn't be on the bumper, it is actually being placed a couple of inches in front of the rear axle.<br><br>Thanks,<br>Barry

 

Hey Guys - I have a positive update! <br><br>This weekend I installed a &quot;Rancho&quot; Steering Stabilizer on my truck. I have since driven approx. 50 miles at various speeds with and without a load on the truck. There has been a drastic improvement. The shimmy is practically gone. I now have to really pay attention to my steering wheel in order to feel anything. There is still a very small irregular feel in the front end that is noticable at around 60 mph. It's what I would expect to feel if I had a belt/cord about to break in one of my front tires - but again, it's hardly noticable.<br><br>I'm beginning to think that I have something loose in my steering and that once I reach 25mph or 55mph something sets the shimmy in motion and the looseness in my steering system makes it almost uncontrollable. The steering stabilizer definitely has &quot;band-aided&quot; the problem but I'm wondering where I should go next in an effort to nail down the real cause of the problem.?.? Any ideas out there???<br><br>Thanks for all your help thus far guys,<br><br>Barry

 

Barry,<br>Have you checked your front end U - joints yet? A tight u joint could easily cause some of the symptoms you are describing. When I had one of my u joints go bad, it was more of a binding and then a release on the steering, but I think they could and should still be considered a culprit until they are checked. The easiest way I can think to do this would be to pull off the tie rod end on one side of the truck and spin the wheel. See if it wobbles at all, and if it does, your best bet is to replace the u joint. Good luck, and I hope this helps

 

Im not sure on this ,but it seems dodge has had problems with the steering shaft going south. The coupler rubber wears out, and I am not sure if this would effect this. Ive seen ads for the Borgleson, ( I think) shafts in 4x4 mags. Also hows the play in the steering box?? You can adjust this yourself. Glad the steering damper helped. I realize its a bandaid of sorts ,but most trucks come with them anymore and I have found if they are shot or removed it starts to shimmy.