Help with Death Shake/Wobble

[Keith_J]

Sway bars are lateral differential springs, plain and simple.

 

[rickf]

Why do I even reply to threads here?

If you are going to reply just do so from experience and not guess at it or post what you find elsewhere on the internet. Nobody slammed you, just pointed out that you were wrong in your description. You would not want to ask a question and receive bad info would you?

Rick

 

[wayne pick]

If you are going to reply just do so from experience and not guess at it or post what you find elsewhere on the internet. Nobody slammed you, just pointed out that you were wrong in your description. You would not want to ask a question and receive bad info would you?

Rick

Well Rick, if this is not a slam, I don't know what is.
I do not guess at anything, or lookup answers to members questions on the internet. Don't ever question my experience or acuse me of giving out bad info. I have helped many members here, and if that means looking up a part number for a fellow member or directing them to another website that will provide them with better info, so be it. You are like a cross between Albert Einstein, Spock from Star Trek and Sheldon from Big bang theory. Ya got all the answers.

 

[rickf]

Well sir, you are entitled to your opinion. I have never had anyone else complain about my advise in the past ten years. I guess I can see where the one negative rep I got came from. I am sorry you do not agree with me. You will notice there are others that said the same as I. I will say no more. I am here to help, not fight.

On Edit: Thank you for the comparisons, I consider being compared to Einstein an honor and Spock personified a very knowledgeable person so I will also take that as a compliment.
Sheldon.............I don't have a freakin' clue who he is. See, I don't know it all.

 

[swinters]

Hi all.

I've had my m1028 for a couple years and it has always had the occasional death wobble - and just so there isn't any confusion - when I would hit a bump just right I would get VIOLENT shaking of the truck with the steering wheel pulling side to side until I slowed down enough for it to stop.

In the past it would only happen occasionally.

I replaced the steering stabilizer and the Tie rod (garage said it was bent). And that seemed to really help it - but would still occasionally do it.
I purchased the king bin spring/bushing kit - but didn't get around to putting them in as the death shake was still pretty sporadic.

Then, this weekend, I was driving a load of wood to my dads house and not long after I pulled of the highway and onto a secondary road, I got a bad Death Shake - and then after that - the problem became chronic!! It would go into a violent spasm on practically any bump I hit - I had to keep the truck at 25mph or less and avoid bumps or it would happen every time.

So I unloaded the truck and rotated the tires and then we replaced the king pin springs and bushings with the kit I bought a year ago, and that seemed to make it feel a little tighter, but I got less than a mile down the road - and then Bam - Violent shaking again.

So, what is next???? Something clearly has happened which made the problem go from occasional to an almost constant condition.

With the front end jacked up the wheels feel pretty tight - no side to side or up and down motion noticed.

Any suggestions would be greatly appreciated - as my truck is now stuck at my dads house and I have more wood to haul soon.

Thanks!!!!

Any luck with your truck? Don't be distracted by the sway bar/torsion bar discussion since it doesn't apply to a stock M1028.

 

[Keith_J]

My 1986 M1031 has developed the death wobble. It only has 13,000 miles on it now, 9000 when we recovered it in June. All was fine until two weeks ago when it went into severe wheel hop at 35 MPH indicated, about 32 MPH actual.

It only does it going down hill coasting, the slightest bump sets it off BUT it isn't predictable. I've replaced the shock absorbers and will do the steering damper as it too is leaking. The shocks were shot. No visible cracks on the frame where the steering box mounts. No play or wear in the tie rod ends. Guess the kingpin rebuild is in the future as steering seems less precise. Off to the -34 to see what that entails.

 

[Anubis8472]

Might I suggest .....

If the death wobble can be related to the track bar on such equiped vehicles.
The Chevies not having said track bar.
Perhaps try looking at the component that performs the function of the track bar.
That being the leaf springs.

It might be a good idea to check leaf spring perches/U-bolts, bushings, shackles.
It may be gaps from wear in these areas allowing the axle to 'shimy' side to side the way a loose track bar would.

...just sayin

 

[cliffyp]

I get them at around 35 mph if I hit a bump at an angle. If I go head on it doesn't happen. I replaced the steering dampener and it made a huge difference. The wobbles try and come on sometimes but I can tell the dampener is holding it back. I have the stuff to do the kingpins so hopefully that ends it for good.

 

[rickf]

8472 beat me to it, it is not real common with Chevies but with the weight on the ground, preferably concrete or pavement have someone rock the steering back and forth. Put enough input into the turning to just start to turn the tires. Have them keep this up while you go over every part of the front suspension including spring bushings and shackles. There will be a small amount of movement in the shackles but you will know if it is too much. The problem with a lot of these trucks is that they sat forever and the grease dried out in all of the parts so just because they have low mileage does not mean they were well greased. The fact that you say any bump will set it off tells me something is loose, you just have to find it. And do not let anyone tell you it is the stabilizer! It is not. The job of the stabilizer is to isolate the steering from pothole shocks and the such like that. It's job is not to mask a loose front end part. If you do not find anything loose then it is time to do the king pins. Something that sudden will not be the king pins though. Are you running with your hubs locked? If so then check the outer u-joints for stiffness.

Rick

 

[Keith_J]

The steering stabilizer is dripping oil, it needs swapping. Also, the shaft is corroded. I tried to induce DW this morning while going to get the part, it never happened. All other times, the weather has been in the low 60s, this morning it was 38 F. Thicker oil made the damper work? Don't know, will report back once the new one is in.

 

[o1951]

I helped tow in the results of a Chevy 3500 getting the shakes at about 45 MPH after a pothole. The right front tie rod busted as the driver was slowing down. Right front wheel went sharply to the right, truck went right, over curb, through some signs, across sidewalk, even though driver turned steering wheel to left. Close call, no injuries, bunch of tickets from police. As I remember, only had about 60,000 miles.

That was over 20 years ago, but I can still picture it. I will not drive a vehicle with death wobble - do not want the risk of killing someone.

 

[o1951]

Rick is right! A new stabilizer can mask loose front end parts. The damping may stop shakes, but has not corrected the loose parts.

 

[Keith_J]

Got the old stabilizer out and new one in. The old one had a dead spot in it where there was no damping at all. At the very least, there won't be an oil drip on my driveway now. Just letting it sit for an hour made a 3" oil spot on the driveway. The damper was shot.

While under, I noticed the spring bushings are rotted and cracked, this will cause issues so I have those on order. Also will look at king pin bushing and spring, ORD has these for $28 which is a good deal.

 

[o1951]

While under, I noticed the spring bushings are rotted and cracked, .

I think you found problem!

 

[Keith_J]

I pulled the wheels and using a jack under the hub, felt for any play in the upper and lower king pin joints, none found. Lubed every zerk fitting and slapped it back together. Naturally, no spring bushings can be found locally. So off to my go-to source, Rock Auto. $35 for all 4.

 

[FLINT]

Hey guys, thanks for all the help/suggestions.

I haven't been able to do anything with the truck yet - its at my parents house which is 3 hours away and i don't get down there very frequently - and when I have lately, its not been for long enough to work on the truck. I did check the frame for cracks around the steering box and didn't see any at all. we also checked the tie rod fittings and they all seemed fine - and like I said before - we already replaced the kiing pin springs and bushings.

What I'm thinking of trying is to replace the front shocks and the spring bushings. although, I was wondering if I should replace the front springs while I'm at it ??? I hate to if I don't have to because they are not cheap.

Who makes a decent shock for the CUCV that isn't crazy expensive? any good reasonable heavy duty ones that are well liked ??

Thanks again guys, I really need to get working on this - we got 4" of snow today and its not convenient to not have the truck.

 

[rickf]

The stabilizer will mask the problem, a new one might even make it go away, until the problem beats the stabilizer to dearth. A properly set up front end will not need a stabilizer at all. I have not had one on my 1008 since I got it 12 years ago. The original was bashed in so I took it off and never replaced it. I started to feel the shakes a few years later but before it got bad I started looking and a quick tape measure alignment check showed I was 1/16 towed out. Reset it to 1/16 heavy towed in and have had no problems since. By the way, I set the toe with the tape measure even though I have access to a laser alignment rack. Just as accurate and quicker. Running rocky trails in Virginia this year I wish I had the stabilizer but that is exactly what it is for.

 

[Keith_J]

But when the stabilizer has a Class III leak and is staining the driveway, replacing it isn't a bad idea. And it had a dead spot with no damping, right at the critical range of travel. I've found the problem with the rotten front spring bushings and will replace ASAP. I've also pulled the wheels and checked king pin play, using a second jack on the hubs. And I adjusted the alignment, centering the wheel and getting 1/16" toe in.

 

[rickf]

I agree that the stabilizer had to be replaced. The bushings will always look bad on the outer edges, that is why I said to have someone turn the wheels and see if they actually are bad. The part hanging out of the side of the spring really does nothing, it is the inner part that counts. With the stiff spring that is in the king pins it is tough to get a read like you do with ball joints or two wheel drive pins. Unless the spring is broken you will not feel enough play to notice even if they are bad.

 

[tstone]

I have had this issue with 2 of my 1008's and have found the issue was with the kingpin bushings and springs. When the spring wears, losing it's factory compression, the spring will not hold the bushing in place tight enough to keep the kingpin from oscillating off center when hiting a bump, pot hole, etc. I have corrected this problem by replacing both the bushings and springs but have even found that some of the new springs don't have the same compresion strength as the OEM's. I have been able to completely eliminate the issue by adding large plate washers between the spring to help increase compression on the bushing; add washers incrementally until the problem stops. Generally 3 or 4 washers will work. Balancing tires, fixing other loose steering issues, etc. will add to the elimination of the overall problem. All of my trucks including the shop body trucks all had low mileage on them but the spring compression was greatly reduced due to age, after making the retrofit I have not had any reoccurance of the problem. Good Luck!