Launch Shudder and Vibration

[MChilds]

I’ve had a launch shudder and shudder/vibration in my truck since new. It’s worse when I tow a trailer but it is always there. Dodge has effectively stonewalled me suggesting I replace the shocks, balance the trailer tires and align the trailer, balance all the truck tires again and again, install air bags, they claim the trailer is too heavy, (it’s not) they claim it’s the first time we’ve ever heard of this problem, etc. I could almost live with the launch shudder (except when the truck goes ballistic when trying to back up) but the shudder/vibration at normal highway speeds is so bad now, I can’t pull the trailer at all and anything over about 65MPH will just about shake you out of your seat.



I’ve had it to a drive train shop and they removed and balanced the drive shaft and checked the angles and parallels, which they say are off and may be causing the problem and after $300 worth of balancing and Goodyear replacing the tires, it’s not the tires. In any event, I’ve asked for arbitration to see if I can get DC to buy the truck back (since they won’t try to fix it) and was hoping for some advice or anyone else’s experience with this type of problem.



Sorry for the long post, any help would be appreciated.

 

[work2muchplay2little]

Several possibilities - if you have a long bed, might have a bad carrier bearing, might be bad u-joints, out of balance drive shaft, loose or broken motor/transmission mount. All I could think of off the top of my head. I'm sure some other ideas will come along presently. Have you tried a different dealer? Sounds like this would be readily reproducible.

 

[Bill Kondolay]

Is yours a 2 piece driveshaft or a 1 piece driveshaft?



If it is a 1 piece driveshaft usually a 2degree shim between the spacer block and the leaf spring will help .



If it is 2 piece driveshaft putting a 1/2 " spacer or 1 " spacer between the hanger bearing support and the frame does the trick.



One out of every three trucks that go through my shop with a 2 piece driveshaft need some sort of spacer.



A lot of chrysler dealerships know of this problem and have a shim kit available to do the job.



This shuddering thing usually gets mistaken for a clutch problem or a transmission problem on the automatics.

 

[MChilds]

Shudder/Vibration

Thanks for the quick replies. It’s a two-piece driveshaft and if I understand the ‘fix’ correctly, the ½” to 1” spacer would move the CSB lower. I’ve shimmed the CSB down about ¼” and that made it worse but I sure can try the bigger shim. I also tried a 1-1/2 degree shim at the leaf spring.



Do the trucks that come through your shop shudder at speed, or just on launch?

 

[Cobra]

shudder

mcChilds

DC does know of this problem. Mostly it is the carrier bearing I think. My 01 2500 does it at launch only. I originally thought it was the clutch. At the time I had air bags on the truck and when I pulled a trailer or hauled my slidein camper it did it. Took it to the dealer and the mechanic said it was because of the angle due to the air bags. I removed the bags and now it does it when empty but not loaded. Go figure. Anyway the truck still has lots of miles and two more years of warranty and if it gets worse I'll get serious with them and they can't blame my air bags.

 

[Briar Hopper]

I had this same problem, it turned out to be the front u-joint on the rear driveshaft. It only shuddered from 0-19mph, then it would go away, and come back at 60 mph & above.

Two Dodge dealerships and a tire store couldn't find it. It was only found by dropping out the driveshaft and inspecting it.

 

[MChilds]

Shudder/Vibration

Thanks Brian. Actually, you’re the first person I’ve heard or talked to that had my exact problem. DC’s brushed me off because they think I’m complaining about nothing and of course, it’s the first time they’ve ever heard about the problem. Unfortunately, I have already had the drive shaft out, balanced and inspected by a local drive train shop. They also replaced a rear u-joint on the rear shaft but it didn’t help.



I’ve been sure this problem has been drive shaft related for 20,000 miles now. I’ve asked for arbitration and I’m going to show them these posts. Maybe they’ll replace my drive shaft with a new one along with a new carrier bearing. Up to now, the two worst Dodge dealers on the planet; West Loop Dodge and Longhorn Dodge in Fort Worth have done nothing but give me a hard time and refuse to work on the truck. DC's total help with this has been limited to suggesting I arbitrate.

 

[MidwestMotorman]

lower the t-case

Another rammer had a similar problem about a month and a half to two months ago. He made a 1/2" bar stock spacer for the crossmember and lowered the transfer case down. He said "problem solved" and posted a nice pic of the job that he did himself. You will then have to lower the hanger bearing assembly to match.

 

[MChilds]

Shudder/Vibration

Nathan,



Thanks, there’ve been a couple of posts about lowering the carrier bearing or transmission. I’ve chased this problem with shims and lowering the carrier bearing temporarily. While that helps the launch shudder, it either doesn’t change the highway speed shudder/vibration or makes it worse. I’m stumped and have already spent a lot of money trying to fix this problem on my own because DC and its dealers have refused to work on the truck or honor the warranty. It’s their opinion my trailer is too heavy (it’s not) and the latest reason is that the truck has a Pac Brake. Go figure; a Pac Brake causing a drive shaft vibration. Now that I’ve asked for arbitration, I’m afraid to do anything else they can accuse me of. They can’t fix it so they try to make it my fault.

 

[Briar Hopper]

MChilds, forget about the dealers. And arbitration is a lengthy, drawn-out mess, in my opinion & experience. You need to find a reputable drivetrain/general repair shop near you to help out. Dig up a few copies of the TDR magazine, look at the advertisers in the back of the magazine, theres bound to be one somewhere in Texas who can help.

I know about Jeff Prince in Corpus Christi, TX, he may be able to help. He is at Performance Diesels, (361)985-1673.

Can some of you Texas boys speak up, and help a fellow member find a good garage to go to?

 

[MidwestMotorman]

By any chance, have the tires been trued? Goodyear had/has a terrible problem with tires being out of round. Also, it could be that someone did not use two tapered lugnuts to center the rims before tightening the regular ones (the service manual specifically states this). Any chance it could be a limited slip growling?



I would try jacking the rear completely off of the ground and running it that way. One can see if any tires/rims are out of round or the driveshaft is not true. You should also be able to hear any noise produced by something amiss. There have been lots of problems with Dodge drivetrain and angles. You could also have a harmonic vibration produced from the six speed echoing throughout the drivetrain.

 

[Lsfarm]

Driveshaft shudder

My 2001. 5 truck came from the factory with a 2WD two piece drive shaft. The center carrier bearing was too high, and created too sharp an angle for the Ujoint.



The fix was a new driveshaft with the 4WD carier and bracket.



You might try droping the carrier lower than normal.



I just went out to the garage, and measured the factory bracket, it is 5" from the crossmember to the top of the carrier bearing, 8" from the crossmember to the center of the driveshaft. the drive shaft is essentially a straight line from the trans to the differential.



Hope this helps Greg L

 

[MChilds]

Shudder/Vbration

Thanks again. I agree with BriarHopper, the dealers are useless however; I’ve already had the drive shaft removed and balanced and a u-joint replaced. I guess I’m a little peeved that I bought DC’s best truck and have had to try and fix the problem myself, under warranty, all with no luck. I’ve tried shimming the carrier bearing down as well as shimming the rear springs. The drive shaft shop checked the angles loaded and unloaded and came to the conclusion that the parallels are off, but the angles are OK. I would like to at least have a factory rep look at this truck but all my calls to DC have been ignored and so far, they’ve done nothing except suggest arbitration.



As for the tires, nathanbush is right; Goodyear tires are bad and in this case so is one of the rims. I’ve had the tires trued, balanced and re-balanced and removed the bad rim. Goodyear replaced a tire that was out laterally. There is no harmonic vibration at all any time and the shudder I get is really side-to-side and phases in and out. I sure would like to hear from a shop that has had this problem and fixed it around Fort Worth because if arbitration is as bad as DC has been, I’m going nowhere in a hurry. Except maybe to my local Ford dealer...

 

[MChilds]

Sudder/Vibration

Greg, I’m going to use your measurements and check mine first thing tomorrow morning. That’s real useful information and I really appreciate it.



BTW, the best thing about owning a Dodge is the TDR and its members.

 

[MidwestMotorman]

Has the dealer done an alignment check? I would rule out a spring hanger or bad bushing. Maybe a limited slip problem?Anyone check for loose spring bolts or axle U-bolts? I would even swap the axles and/or drums from side to side to check for one of them being out of round or balance. The key to solving this is persistence and one step elimination.



Perhaps all of our Dodges have vibrations, and whether we notice them or not depends upon our level of sensitivity.



BTW, Ford and their six speeds are not any better than Dodge and its six speeds.

 

[MChilds]

Shudder/Vibration

Nathan, I’ve had the alignment checked and done my own check and double check of loose spring bolts, U-bolts etc. I’ve mounted other wheels from another truck just like mine (that doesn’t shudder) and it didn’t change anything. The axle swap is an interesting suggestion; I once had a Ford truck (old and out of warranty) that had a bent axle. I thought I would never find that vibration. But it was a vibration that was constant and predictable with speed, while my current problem is a shudder/vibration that phases in and out. Over the past 20,000 miles of driving torture, I’ve narrowed it down to drive shaft or something really stupid, like the rear differential pinion out of round or eccentric.



My level of sensitivity is probably normal to more sensitive but at speeds over about 65MPH, this truck shudders and shakes and thumps so bad it’s scary. My wisecrack about going to Ford is a last ditch effort, I like my Dodge. My 6-speed works as good as any transmission I’ve ever owned, no complaints there.



If DC would just try a little and swap a few parts, I know the problem could be solved. I remain stunned by their stonewalling and absolute unwillingness to address the problem. It’s almost as if they want to chase customers away to teach Daimler a lesson. Reading articles on DC’s massive loss of market share tells me their tactics are working. Just think, the Big Three is about to become GM, Ford and Toyota.

 

[MidwestMotorman]

Some vibration that phases in and out is usually always a balance problem. Being yours is a 2WD, about the only thing suspect is the rear driveshft and rear end assembly. I know dealers do order/warranty whole driveshaft assembly because others here have had it done. Swapping the whole rear axle would be a chore, but you are down to two possibilities. I would not rule out a rear drum being warped or out of balance. Did the dealership even pull the rear drums to check for a bad bearing or to check for play?



When I used to be a GM service manager, we did have persistent problems. But I always tried a different fix and never gave up on something. The words "Sorry, we can't do anything to fix it" were unacceptable in my book.

 

[Lsfarm]

Shudder

MChilds, the shudder that I had on my 4x4 was so bad that I turned around and went back to the dealer, [with the brand new truck] got a mechanic [tech. ] and took him for a ride. My truck growled and shuddered above about 68 mph only under load or climbing a hill. From 70-80 pmh it was terrible.



There was a pronounced bend in the drive shaft aft of the carrier bearing at the middle ujoint. this angle was too much to transmit the power through without 'some' vibration.



Your rig is 2WD, but it is a 3500, so I would check to see if the drive shaft is in a straight line from the trans to the diff. Shim the carrier to make it so. give it a try.



The dimensions I gave you last night are probably no good for your 2WD truck, sorry. But the straight driveshaft observation may help.



Good Luck!! Ps: try some other dealers!! a one or two hour drive may be worth it!!



Greg L

 

[MChilds]

Shudder/Vibration

My drive shaft does angle down to the rear axle but shimming the carrier bearing down to make it visually straight doesn’t fix the problem. I’m sure there is a component problem maybe coupled with an angle problem. My truck has rear discs and I’ve put my own dial indicator on them. Remember, the two dealers here in Fort Worth refuse to work on the truck so I’ve been on my own. The other dealers I’ve called within an hours drive or so only say they’ve never heard of the problem or they probably can’t fix it; hardly worth the drive. They do however tell me to call DC, and DC tells me to arbitrate. I’m caught in a catch-22 situation, stonewalled each step of the way.



I agree with Nathan, it has to be in the rear drive shaft or rear axle, or both, but I don’t think I should go out and buy expensive components to fix a clearly defective truck. Shimming carrier bearings, OK. Not to have to deal with the condescending attitude of my local dealers is worth trying to fix it myself. Heck, the intense cross-examination by the service advisor or service manager looking for a way to wiggle out of warranty repair is enough to make me avoid the dealer…maybe that’s their plan…make the customer feel like a criminal for complaining and they’ll just go away.



Call my crazy, but I thought troubleshooting and repairing defective vehicles was covered under my warranty and I’m still hoping against hope that DC will step in and help by either replacing or fixing my truck. Given the runaround I’ve experienced, my expectations don’t run high but faced with the possibility of spending even more wasted time and money on this problem, I’m giving it a shot.



Thanks

 

[Steve M]

My '95 auto had a bad vibration after lockup in third or O/D at around 1850-2000rpm. It was worse under load. There was a TSB on it that stated the vibration was normal pulses from the Cummins engine being transmitted through the driveline. Seemed reasonable to me. The cure was a damper on the front driveshaft right at the first u-joint. It worked great. Just a thought...

All three of my Dodge/Cummins trucks have had launch shudder. You can change the angle of the pinion and clear it up unloaded but then it'll be worse loaded and vise versa. I don't know if a set of traction bars would help by holding the axle from rotating at launch but theoretically it seems like it would. The long springs that help the ride also let the axle rotate slightly at launch.

I went back to an automatic to get away from the extra driveline vibration and noise of the standard. Most folks don't even notice it but I found it irritating.