Stock Truck, Stock Tires, DEATH WOBBLE!!

[sag2]

Both times you mentioned that you were pulling a trailer. How does the truck sit with the tongue/king pin weight on it? If it is low in the back, chances are the front is high, and you are loosing caster. Not enough positive caster and it just adds to any problems you might have with worn parts.

 

[PGiannetto]

In the last 2 weeks it has happened 4 times. 2 with a trailer & twice without. I will start taking to Dodge this week.

 

[Greg Boardman-RIP]

sag2 brings up a good point.



Has there been any caster changes in the last month? If so, you could always put it back to 2. 5-4. 5 degrees. I would bet that it is a bad tie rod end and a loose steering box. Those are the most common causes on a completely stock vehicle.

Greg DRC

 

[THUREN]

Changing shocks will not fix it. Changing springs will not fix it. Changing tires will not fix it. It Is A series of bad Parts!!! I Guarantee it!



Greg DRC

Hi...



I don't know Greg, I VERY RESPECTFULLY disagree, and see DW in a different light as I have been dealing with this a lot lately also...



Without going into more stuff..... doesn't it seem strange that some DW is STRICTLY speed related, and some will NOT happen till you hit a good bump?



I would have agreed with you about a year ago, on the shocks not having anything to do with DW, but after dealing with this one truck first hand and the shocks fixed the wobble, it made me figure out why... Not saying in any way the every truck with DW needs new shocks, it's just an option if you only get DW when you hit a good bump... .



Don

 

[Greg Boardman-RIP]

Don,

If you remove the steering stabilizer, does it come back? I have seen DW with race shocks on trucks. Most of the time, DW has been speed related in my experience. Anyway, here is my experience:

70-74 mph

Flat ground or road

Straight line of travel

encounter a small "roller" style bump

Truck goes into DW.



I have seen it come in other ways but you are right, speed related is the key. Why do you feel a good shock is the cure? I have a belief that the DW is an occurence of many things happening at once to cause the sensation. You insight could be of great assistance to us all... .

Greg DRC

 

[THUREN]

I'm gonna' try and explain this the best I can w/o getting too long and confusing... I hope it comes across clear... And this is just the "why shocks could be a factor" part of this...





Allright... Since the control arms do not sit level they will travel in a forward arch under compression which would be even more pronounced when a lift is installed. What I think is happening is that the "bump", usually a sharp edged one, will cause the axle to rapidly compress and "bounce" with cheap/worn out shocks. When the axle quickly swings back I feel this "front to back" movement is transmitting into the tire to "swing it" getting the DW started... All it takes is to get it started, however, or for whatever reason... . And with this dead spot there would be no valving taking place to control anything if it happens... .



My reasoning behind the "cheap shock" deal is this. It would be exactly the same as lowering your race shocks nitrogen pressure down to 25psi. Under compression the nitrogen pressure is too low to keep from pulling a vacuum under the piston head causing a "dead spot" in the shock when taking a quick hit. This wouldn't really be noticable, would take an extreme amount of weight and valving to get it to happen, and a CTD sure has that. . If you had Bilsteins, kyb's, or any other "high pressure" shock this obviously doesn't apply... .



It's just the only thing I can come up with as to why "shocks" fixed this truck...



Don

 

[PGiannetto]

Does the DW happen to the gas rigs??

 

[DPKetchum]

I use to see the DW in Datsun/Nissan cars and trucks. Was ALWAYS tire releated on them.

 

[Rockcrawler]

Thatks for replies. the reason I started a new thread is because 95% of trucks with " death wobble" have been lifted trucks with different size tires. Then most of the solutions have been "stay with stock" & " you need load range E tires". My point is I have a stock truck & stock tires. Anybody else having this problem with completey stock trucks? If so what cured it? thanks!

Kind of pokes a hole in the ballon for the "sky is falling cause you put bigger/wrong size/xxx brand/load range d" tire crowd.



There's a bunch of variables involved, wear patterns, cord separation, balance, worn parts, incorrectly adjusted parts. If under warranty and your dealer is not talented enough to fix it, find another dealer. You may end up buying new tires to fix the problem which could be out of warranty, unless it's cord separation.

 

[PGiannetto]

I only have 12,000 miles on truck & tires.

I was wondering if the Third Generation Gas rigs (4x4 2500) were having the same problem?

 

[NVR FNSH]

Does the DW happen to the gas rigs??

Yes. Search on my user name for the saga of my '96 2500 4wd CC SWB 360 V8/auto. I installed the stock tires from my '00 2500 4wd on it and the dealer threw a new track bar, second steering stabilizer, new ball joints, new upper/lower control arms and new wheel bearings at it. None of these solved the problem. Truck already had Edelbrock IAS shocks on it - made a huge diff comprared to stock.



What's missing from the above shotgun approach? An alignment. When the dealer installed the new control arms they marked the eccentrics on the lower control arms and installed the new arms to the same location/same caster. I increased the caster in my driveway and the DW was gone... ...



My '79 CJ-7 and '85 Toyota 4wd get DW. My friends '79 Ford F-350 4wd also gets it. It's not a Dodge Cummins specific problem.



Brian

 

[PGiannetto]

months ago I installed Ranch 9000 shocks set at 5. I have not had the death wobble since. I now have 28,000 miles on my rig. thanks for all the help!

 

[JSitarski]

I had DW with Bilstines 5100's on the front and did not make any difference what so ever just made the ride stiffer. I hade the 4 ball joints replaced, all tie rod ends, steering shock all under warenty. Dealer told me since I had a 3" front lift to try replacing my controll arms at my expence' so I did, and i got a track bar relocation bracket, I also installed 2 lukes links on the pitman and the drag link, set caster to as much as it will allow. And still DW. I orderd a set of front dual shock kits and put them on. And It is gone. Thank god!!!!

 

[Big Sur]

I can't believe DC hasn't been sued into Bankruptcy with this front end design. It could seriously take lives.



I run 5100s and had DW; it cleared up with new tires ("D" rating Liberators replacing "E" rated Mastercrafts). Luke's Link in place, everything tight. So far, so good. Thuren bar on order ...

 

[ToddYoung]

You know that I just drove cross country and never had a problem. I hit many bumps on the high speed interstate system that we have in our country (ya right!) going ever speed from 0 - 100. With 35" and a lot of weight in the bed not a one hint at DW.

 

[horned Toad]

I would agree with having the alignment checked, the front of my stock 05 2500 started bouncing at 15000. It was an up and down not a side to side. They put shock on it and it helped, but was still there. I took it back and they checked the alignment. The truck was towed way out from the factory with the front right being way out. They fixed that and it is a lot better but it still does not feel planted like my 03 work truck.

 

[horned Toad]

Does the DW happen to the gas rigs??

I put 50k had miles on an 03 2500 4x4 quad short box that was daily carrying about 800 pounds and has had up to 3000 pounds in the bed, I had one issue with wheel bounce and it was from worn out stock shocks, they were replaced with a generic HD gas shock and that fixed the problem. Being that this thing had lights and sirens on top it spent a large amount of time with the speedometer sitting at 105 and was rock solid.

 

[SCarli]

Hey guys,

Thought I would share my experiences with the DW. Have had many trucks come through the shop with the problem. First I have to start by agreeing with Greg and Don, there is no one fix. I have changed out tires on a truck and solved the problem. I have replaced worn out wheel bearings and solved the problem. I have also added dual stabilizers and solved the problem. My take on the reason behind this is front end steering "y" design combined with the short control arms. As the axle goes through it's cycle it moves down and to the left extending, and up to the right compressing, meanwhile the toe is changing in a rapid fashion at the same time. This creates alot of movement at one time. If there is any loose components in the steering, blown shocks, soft side wall tire, or worn track bar it will allow the axle to move at will with little resistance. If the pivot points on the control arms were moved further back, then the movements of the axle wouldnt be so sudden. Take the new Ford F250 for example. They are a three link system with long raius arms that are almost parallel to the ground. The only death wobble I have ever seen on one of those was when a shop had done a lift and left the pan rod loose at the frame end. DW is annoying and sometimes just scary, but can be cured. Everything that connects to the axle must be tight and good working condition along with the proper tires and alignment.