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Discussion Starter #1 (Edited)
My 97 4x4 gets death wobble at seemingly random times. Like I don't necessary have to hit a bump any certain way, sometimes it just seems to starts shaking as I accelerate. Almost everything in the front end has been replaced, the only things that I personally haven't replaced is the steering box itself and the ball joints (both of which seem in good shape, hence the reason I haven't replaced them).

Its got 98-99 HD t-type steering (done with moog parts), a synergy track bar, new moog unit bearings, and a cheap steering stabilizer shock. Its been aligned by a local shop, the steering wheel doesn't pull in any direction, and overall it drives pretty good (when its not wobbling)

I don't have a steering box stabilizer bracket, but I do have a front receiver hitch that bolts between the front frame rails.

Would one of the steering box stabilizer brackets (that are available on everyone's website) be worth the $200-ish they cost? I figure there's a reason that everyone seems to sell them, but that logic doesn't always hold true. Thanks
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Have you tried rotating tires? Death wobble is usually because of out of balance, or out of round tires.

The gearbox brace is more to help to keep the sector shaft seal from being twisted when turning larger tires. Some say it does help a little with their steering wander. However, my personal experience is that I noticed no change with that as you shouldn鈥檛 because the sector shaft goes through a bearing, so it should spin as smoothly as before. I bought the box stabilizer because I鈥檓 running 37 inch tires and have already replaced the sector shaft seal once.

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Discussion Starter #3 (Edited)
Guess I should have mentioned that I also run centramatic tire balancers as well. So the tires /hubs / rotors / all the rotating parts really, are balanced by centrifugal force. I've found they're the easiest way to keep bigger tires happy an Texas highway speed limits. (BTW, they work great, I can drive this thing at 85 mph, which is the speed limit in some places, on 37 inch mud tires with no vibration).

The death wobble I get is ALWAYS in the 30- 50 mph range. Sometime if its not to bad ( like injury wobble ,vice death wobble) I'll just push through it by continuing to accelerate and it'll stop shaking.

But to answer your question, no, I haven't tried rotating tires, because I figured the centramatic balancers would take care of any out of balance issue.
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I鈥檝e heard good things about those balancers and want to try a set out myself.

Hmmmm. Have you crawled under and had some one turn the wheel?


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Are you 100% sure its death wobble? Only asking because when I had a UJ going bad on my driveshaft I experienced the same thing, it was a pretty severe shake/wobble that I could feel in the steering wheel. I would have swore it was coming from the front end as well. Just a thought!
 

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Discussion Starter #6
I'm only 100% sure about like maybe three things in life. I replaced all the rear driveshaft u-joints (including the carrier bearing) when I did the clutch 20K-ish miles ago, and I haven't really looked much at them since.
But what I'm calling death wobble definitely pulls on the steering wheel and sure feels to me like it's in the front end. I'll do a visual check on the rear u-joints just to see though.
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I feel you on that one! I've experienced death wobble in quite a few truck but they almost always happened after hitting a slight bump in the road. Its kind of weird that yours happens randomly even without hitting a bump.
 

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What tires .
What castor #

On my 05 i replaced every single component ( except the steering box ) . Still had near DW .... AND IT WAS THE TIRES ,, some cheap azz Falcon or Avon or something . Hated them.
 

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Discussion Starter #9
The tires are BFG mud terrains, 37 x12.50 on 17 inch wheels. No idea on the actual castor number, the shop I took it do didn't give me print out of the before and after that I recall.
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What track bar do you have?
 

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Discussion Starter #11
What track bar do you have?
I have a synergy adjustable that gets rid of the old ball joint, it has a rod end on the axle side and poly bushing on the frame side. Unfortunately it looks like synergy stopped making them because I went to order one for my son's truck and no one seems to have them anymore.
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The tires are BFG mud terrains, 37 x12.50 on 17 inch wheels. No idea on the actual castor number, the shop I took it do didn't give me print out of the before and after that I recall.
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Caster is your most important unknown here. Factory spec is likely not enough because of the tire size.

Are you using stock-type deep backspace wheels by chance? You may find that any setup that moves the tire outboard (wheel spacers, less offset wheels, certain freespin kits) may have a calming effect on the DW because it increases scrub radius.
 

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if suspension components n steering components abs tires are good, look at toe n caster. caster fixed mine. night and day
 

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I ran centramatics on the front of my 06 3500 (33's) and ceramic beads in the rear duals. I run ceramic beads on the (35's) front and rear now in my 2007.5 and i'll tell you why - I love the centramatics - I think they're one of the greatest things since sliced bread. But I have found that the transition from an unbalanced state to a balanced state is much smoother with beads. I had a weird vibration on my 2006 with the centramatics between 20 and 30 mph - I'm not sure what the weight of the balancing beads was inside the centramatics, but it is my understanding that you have to spin them at a certain speed in order for them to work. My 2007.5 has that weird vibration between 25 and 35 mph, and it is my assumption that I have the vibration in that speed range because my beads weigh more than the balancing medium in the centramatics. I'm willing to bet that you don't have enough weight inside the centramatics to effectively balance the tire. When I talked to a guy from centramatics several years back he told me not to run both - he said run beads in the tires or run centramatics, one or the other - that they would fight each other and remain in an unbalanced state all of the time. I'd like to see your tires pulled off of the truck and machine balanced dynamically, then placed back on the truck (without the centramatics first) and what i'm wondering is if you'll still have the same vibration in the same speed range. I'm also wondering how much weight will be required to machine balance your front tires. I probably run an extra ounce or two of weight - maybe a little bit more than I should - but I figure that's better than not having enough.
 

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CASTOR, its the only thing that matters to prevent death wobble. factory spec is waaaay waaay too low and the trucks need 3.5 degrees positive castor minimum (ideally closer to 4). factory spec can be listed as "good" with as little as 1.8 degrees
 

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I like 5 degrees as a starting point for any solid-axle. (y):sneaky:
 

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The tires are BFG mud terrains, 37 x12.50 on 17 inch wheels. No idea on the actual castor number, the shop I took it do didn't give me print out of the before and after that I recall.
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BFG tires are the common denominator in a large percentage of cases where the suspension components are tight.
 
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