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death wobble

4K views 23 replies 12 participants last post by  Flanman55 
#1 ·
2013 ram 2500 CCSB g56 4x4 with 111xxx miles. I have a carli commuter with all the options, new steering box, synergy tierod and sttering, new ball joints installed just the other week. I am running 285/70/17 tires. on my trip home from vacation today i had death wobble 3 times when hitting the transition from highway to bridges in West Virginia at 75 mph. Everything is new upfront and I have had 2 different shops look at it. what could still be causing this. the tires are an off brand, could they be the cause of it just not being a good tire? i want new wheels and Toyo tires but that requires some saving.
 
#3 ·
yes its just a single. but what is causing the death wobble? I'm not looking for a bandaid. I want to fix the issue
 
#4 ·
There was another thread very recently, and the off brand tires were the culprit to the surprise of a number of members. Inadequate sidewall stiffness. Some of us having experienced other totally crazy instabilities in off brand tires were less surprised.

Check your caster settings. Make sure your cams are symmetrical side to side and that you're running spec or more positive caster. Set in near zero toe. Make sure your tires are pressurized properly.

The single biggest thing you can do to increase the stiffness of your steering linkage -- assuming there are no real problems -- is to mount up a steering box stabilizer. The mechanical slack that allows DW has to come from somewhere, and our steering boxes aren't very rigidly mounted. With your Carli torsion anti-sway, your choices are more limited. A Synergy works. Others too... but I can't remember which ones. A Rough Country won't work with the torsion anti-sway.

Make sure your tie rod and drag link rod ends are solid. The aftermarket parts are robust but they can go bad.

Make sure you don't have a lot of slop in your steering box.

Make sure your steering box mounting bolts are tight.

Bearings bad enough to allow DW should cause other symptoms. Your ball joints are new.

Steering tie rod stabilizers -- the viscous shocks between axle and tie rod or drag link -- will damp and mitigate a tendency towards DW, but can't eliminate it if you've got it and won't cause it by failing if you don't. Bad steering stabilizers will not be a failure mode or cause of DW; they can only help to hide it if something else is causing it.

The instability is caused by bad geometry -- bad toe, bad caster, asymmetries, misalignments from damage. The instability is allowed by mechanical looseness -- weak tires, weak ball joints and rod ends, weak or sloppy steering box. The instability is excited by external inputs -- hitting a bump, pothole, or step, or bad tire balance or wheel runout.
 
#5 ·
I put a new Redhead steering box on a year ago, with steering box brace, the tie rod ends were just replaced, truck realigned, I dont know what else to look at all these parts are either brand new or 1 year old. What pressures should I be running?
 
#7 ·
I don't know what your truck's tire pressures are, sorry. A 3500 can run 80 psi all around and needs it rather badly in the fronts all the time, especially a dually on stock skinnies, although the rears might be aired down to 40 unloaded. I would start by checking to make sure you're running maximum rated cold pressure in your tires and then drive like that and see if it gets better. More pressure = more sidewall stiffness = less tendency for DW. It's not a fix... it's a mitigating factor.

Since you just installed or had ball joints installed, alignment is suspect. A 2" lift will throw off any basic shop's ability to correctly align your truck because the computer doesn't know about your altered geometry. The result is usually asymmetrically adjusted caster cams, which will cause instability... bla bla bla. If I were in your shoes, I would air up the tires to max pressure, dial in as much positive caster as I could, and get toe-in as close to zero -- but not with any toe-out -- as I could. See what happens. You're not going to hurt anything by running too much positive caster... you'll just have a lot of on-center feel. Near zero toe is recommended for these trucks.

If you still see DW, the next step is to borrow a set of wheels and tires from another truck with premium tires, provided everything is tight.
 
#8 ·
Yeah.. like B.Lee says, verify load range. Too low a load range = too low a pressure = weak sidewalls... etc. I quoted pressures assuming correct Load Range E1 tires.
 
#9 ·
#10 ·
thanks for all the help and input guys!

The tires are Sailun TerraMax A/T and they are a 10 ply. I know when i finally get new wheels and tires that Carli says to run 37's at 40psi up and 35psi in the rear and they use Toyo tires. That is the route i want to go I found a fuel wheel and i want to pair it with Toyo Open Country R/T 37 x12.5 18
 
#11 ·
If they're Sailun Light Truck size tires with the size preceded by an LT, they're nominally load range E. That having been said, based on my experience with import truck tires -- never, ever, ever again -- I wouldn't trust 'em. That's just me.

If they don't say "LT", they're SUV load rated only.... and it looks like two on the front end could be overloaded on an empty truck.

Check your alignment before you do anything. Crawl under, check the caster adjuster cam-slots. If you have original radius arms your caster adjustment in the positive direction is limited now, unless you have drop brackets. Nasty things, drop brackets... JMHO. If you don't have drop brackets and you do have original radius arms... I'd twist the axle all the way back.

Check your tow. You can do that at home with plumb bobs, duct tape, a long straightedge, and measuring tape.

https://www.cumminsforum.com/forum/...-diy-toe-adjustment-plumb-bobs-duct-tape.html

If your tires are an LT size, you should be able to pump them up to 80 psi. Check the sidewall. If not... I'd bet we found your problem.
 
#14 ·
I'm not sure what it was aligned to but the shop that did it is well known around my area for being the shop to go to. That was the first time it has happened since the bolts loosened up on my track bar. I am home now and will be crawling under the truck to check those again but the alignment was 2 weeks ago.

The tires are a LT285 but apparently they barley qualify for a 10 ply. I was running 70 lbs but they were wearing out quickly so I reduced the air pressure. I will add some air and see what happens for daily driving. I will be needing tires within a few months so hopefully Santa drops off the new wheels for me haha.

Thanks for all the quick and informative replys guys!
 
#15 ·
1. caster, may need to add some.
2. check the track bar, do you have the newest version? I am pretty sure there was a recall for the earlier versions.
3. check the synergy parts, I have seen posts about bad joints on drag links (not sure if you have their link)
 
#16 ·
#17 ·
checked the track bar all is good there. The tire pressure was a little low so i bumped it up to 65-68 somehere in there. I havent checked caster nor do i really know what to look for. Everything looked good and tight and I am really thinking the tires are just garbage and the fronts may have been slightly low. It felt better today.

Now the damn fan clutch is shot....if its not one thing its another! have a wonderful day guys.
 
#18 ·
Slightly out of caster can cause these issues. If you were slightly out of caster prior to the 2” leveling kit, and then added the level, it could be right there on the line where the proper set of circumstances could cause the death wobble. Look up thurens specs on alignment and set to that. Not factory specs , especially with a leveling kit
 
#19 ·
while changing my fan clutch I looked up the Thuren specs and checked mine and that is where they are set. I'm thinking these tires really are a substandard tire and combining that with the low pressures and I believe that is what caused my issue. It only happened at 70-75 mph. I would slow down before every bridge after it happened and the truck was fine. I have since increased the front air pressures and we will see how that goes until i get a set of wheels and Toyo 37's!
 
#23 ·
while changing my fan clutch I looked up the Thuren specs and checked mine and that is where they are set.
...
Thuren recommends lowering the caster to ~4 degrees for the diesel RAM, after setting the toe to 0. That 0 toe really helped me with tire wear.

But have heard here (like posts #4,#15,#16 above), and from my alignment guy, that such a low caster can lead to death wobble. So we didn't follow Thuren on that. IIRC I'm now at 0 toe and ~5 degree caster.
 
#20 ·
Not sure if you have had your tires balanced recently. I had tires balanced at a very reputable 4x4 shop. After I had them balanced, and they were road force balanced, I had a wobble above 70mph. Took to dealer of all places to have a few recalls done, and the 2 rear wheels were mad off balance. Something like 8 and 12 (oz or whatever they are weighted in). They rebalanced them and wobble is gone. I have a 2015 2500 with Cummins and 35s BF on 20s.
 
#21 ·
Man, I have been through this, and I finally fixed it. HD Bilstein Shocks all around, including for the steering dampner, 80psi in all the tires, front end alignment, I never had another problem. I had a 2006 2500 and the Death Wobble would go off with the slightest bump at around 55mph. It was BAD!!! Before this I was replacing Ball Joints etc etc etc and nothing fix the problem!!!!

HD Bilstein Shocks all around, including for the steering dampner, 80psi in all the tires, front end alignment.
 
#22 ·
i don't think tire pressure really has anything to do with it. I run mine at 50/45, no issues.
crappy tires maybe.
there are only a few things that cause death wobble.
 
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