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Vibrations / shaking

4K views 19 replies 10 participants last post by  exracer2 
#1 ·
I've got a 97 3500 dually 4 x 4 that is soon going to get parted out if I can't solve this issue. Since I bought the truck I have had an issue with vibrations at 80 plus kmh (50mph). Problem is it's intermittent. I can drive one day and no issues, the next it starts as soon as I exceed 80kph. I tend to drive under 80 with short Hiway trips of less than 20 mins at a time. So most of the time I forget about it. The vibration is hard to determine the location. Doesn't seem to be front tires. Cant say it is the rear end of the vehicle either. Based on passenger feedback it seems to be more drivers side.

In the last 12 months I have replaced both front hubs, and the bearing for the driveshaft inboard of the CAD. Both output seals for the TC have been replaced. With the front DS removed the pinion will spin while driving. The TC front flange will spin while driving with the DS removed.

Previous problems have included replacement of CAD fork and replacement of CAD motor with a posi-lock. Axle u-joints appear to be ok.

I am suspecting there is an issue with either the TC, front axle carrier /pinion, or rear axle and possibly the transmission (5 speed manual). I don't know what to take apart or start replacing first. Up to now it seems like I am replacing one part at a time only to say nope not that one.

Basically I drive and all seems fine and then i get a vibration as if a tire was badly out of balance but not from the front end as I don't get the steering wheel feeling. As soon as I reduce speed under 80kph the issue disappears. I have tried driving in 4th and 5th to see if the issue is trans related but that us not definitive either. I can drive for an hour and then it just fades away or then gets real bad. Sometimes in the winter it was worse or non existent. I can stop for fuel and all of a sudden it is gone again. I am at a total loss to decipher this one.

At this point I don't drive out of the city and wont drive more than 30 miles if I have to use the highway. I was about to buy a used truck yesterday until i did some research and found out my new old truck may be just as problematic as the current one. I need a reliable truck. This one is not. Short of spending as much as it cost to buy I don't know what to fix or where to start.

Steve
 
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#4 ·
Have you read up on the "death wobble"?

If/when you part out, I want dibs on the engine :D

It does not wobble. It vibrates / shakes. I built my own copy of a steering brace so it is straight when I drive. When it vibrates I can take both hands off the wheel and it goes straight down the road.


But thanks for offering to take my motor off my hands. Glad to see the first response to fixing my issue is to profit on your own. Thats classy. I will be keeping it for one of my own projects so you will have to lurk and find someone else to vulture in on. I think I may just be a bit offended. What do you think? I really hope I can solve this problem with some advice from the forum. Can we keep it on topic and related to FIXING the issue?
 
#7 ·
Have you checked your u joints or slip coupler on the driveshaft if it has one?
Since it"s a dually,; take it for a ride with singles start removing tires on the rear & swapping them around, or just have them balanced. could have one separating? Is the vibration road speed or engine speed ie: if you stay at the same speed & downshift does the vibration change?

liteweight
 
#8 ·
Joints are all good, tires are new. It is road speed not engine speed related. Rims were just balanced. Slight out of round so next step is to attempt new rims or see if existing can be brought closer to spec. Since the problem comes and goes I am not 100% this is rims but what else can I do? Looking at a 2003 so I might go that route.
 
#9 ·
if it is road speed, then try like I said. Remove tires till the shaking is gone. Then you will narrow it down without killing the bank account

liteweight
 
#10 ·
Get 4 good jack stands and put it on them. Have a buddy run it at a steady speed, try im 2 or 4 wheel until it vibrates then jump on yoir creeper and slide under and try to localize it. If you believe its tires then take them all off and try again. The fact that your yokes turn without the driveshaft on in 2wd means nothing, inertia or whatever they call it from the oil slinging will cause that. Most likely you can hold them with your hand if you tried when its on the stands. Oh and btw dont get your knickers in a wad over someone throwing a joke out, thats why most people like this site because we are allowed to have a little fun while we help. Good luck
 
#12 ·
I know you said your tires were balanced so this may be a real longshot. My friend had the same problem until he removed the 9/16s wrench that the installer left in the tire after he installed a new valve stem.

Just sayin...........
 
#13 ·
Truck is getting new (used) shocks a new tie rod end and is off to it's new owner. We determined the rims are not perfectly round ( 3/8) and think this with the worn shocks are the issue. Not going to diagnose this forever. Moving on. Time for something newer that the wife will ride in.

Thanks for the help and I will try to post if this appears to have solved the issue.
 
#14 ·
If your truck has posi it could be the clutch discs in the rear diff starting to go, most likely it's either a ujoint or balancing on one of the driveshafts, I've experienced this on my diesel rams as well as a bad u joint on the rear d shaft on my Tacoma
 
#17 ·
I was having a very similar issue, vibrations at high speed. Balanced tires a few times and no difference. Put the truck up on stands in 4wd and let it roll. Freakn wheels were running out about 3/8". New wheels and now all I feel is how bad the road surfaces are here.
 
#18 ·
I had this on my 2500 when I changed the rear shoes/drums. Cheap whitebox drums were out of balance by 9 oz! I already threw away the receipt so I couldn't return them so I just put weights on the wheels to balance out the drums. The shaking would come and go because when you make a turn one wheel momentarily goes slower and changes its position to the other wheel. Sometimes they counter-balance each other, sometimes not.
 
#20 ·
Truck was sold 18 months ago as is. Problem persisted until day he picked it up.

Problem was not posi clutches, was not... Nor...

Could have been rims, trani bearings, bent front axle etc etc.....


Truck was sold 18 months ago so to be honest I haven't been diagnosing the problem since it left my driveway. I have been thinking about how much I liked the truck and how much I wished it wasn't possessed or at least wishing I could have exercised its demons. But dollar after dollar problem persisted no definitive direction as to its cause so I cut my losses. I am unsubscribing to my own thread because the problem was put to rest a year and a half ago. I can't add anything new nor try any suggestions. Thanks to previous posters and their suggestions.
 
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