Death wobble bs bump steer
1981cj7
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Can anyone explain to me the difference between death wobble and bump steer? Or are they the same thing?
Death wobble bs bump steer
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Most folks refer to death wobble as driving down the road and the front wheels wiggle back and forth. Can be caused by a number of things...alignment, worn joints, etc
Bump steer is when you hit a pothole in the road, rock in the trail and it jerks your steering one way or the other. It can be caused by the same stuff as above.
Sent via Google translate using braille through Tapatalk
Bump steer is when you hit a pothole in the road, rock in the trail and it jerks your steering one way or the other. It can be caused by the same stuff as above.
Sent via Google translate using braille through Tapatalk
1981cj7
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Re: Death wobble vs bump steer
Thank you. I appreciate your response. I believe that I had both. I installed a new steering shaft and upper bearing, gear box(which had at least an inch of ply!), tie rod and control arms, and steering dampener. I also installed a new BDS 2.5” leaf spring lift kit with the front YJ conversion to 2” springs, and Currie shackles. Then got an alignment at the local tire shop. I’m running on 31” tires. The Death Wobble is gone. On a smooth road, it drives great even at 55mph. As soon as I hit a pot hole, all bets are off! It doesn’t jump nearly as much as it did, but it still sends the Jeep on a different trajectory. Recovery is a b*tch. That’s what makes scares the
out of me. What to me seems like not much movement in the steering wheel, makes me feel like I’m going to flip. It sways back and forth a bit until I can stabilize it, which can take up to 5 to 10 seconds sometimes. Does anyone have any thoughts on how I can address this?
Thank you. I appreciate your response. I believe that I had both. I installed a new steering shaft and upper bearing, gear box(which had at least an inch of ply!), tie rod and control arms, and steering dampener. I also installed a new BDS 2.5” leaf spring lift kit with the front YJ conversion to 2” springs, and Currie shackles. Then got an alignment at the local tire shop. I’m running on 31” tires. The Death Wobble is gone. On a smooth road, it drives great even at 55mph. As soon as I hit a pot hole, all bets are off! It doesn’t jump nearly as much as it did, but it still sends the Jeep on a different trajectory. Recovery is a b*tch. That’s what makes scares the
out of me. What to me seems like not much movement in the steering wheel, makes me feel like I’m going to flip. It sways back and forth a bit until I can stabilize it, which can take up to 5 to 10 seconds sometimes. Does anyone have any thoughts on how I can address this?
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Re: Death wobble vs bump steer
There are a handful of things that can cause it. The good news is that you've eliminated some of them with the replacements you've made, which helps narrow down what's left.
You mentioned tie rod...did you do anything with the drag link/pitman arm? Any significant angle at all to it is a major bumpsteer contributor. Ideally you want it as flat as you can get it (parallel to the ground). At 2.5" of lift it shouldn't be extreme, but I'd start there.
Ball joints would be the other thing I'd check, if you haven't already.
Do you have a sway bar? What air pressure are you running?
Just some things that come to mind...I'm sure other will chime in as well
Thank you. I appreciate your response. I believe that I had both. I installed a new steering shaft and upper bearing, gear box(which had at least an inch of ply!), tie rod and control arms, and steering dampener. I also installed a new BDS 2.5” leaf spring lift kit with the front YJ conversion to 2” springs, and Currie shackles. Then got an alignment at the local tire shop. I’m running on 31” tires. The Death Wobble is gone. On a smooth road, it drives great even at 55mph. As soon as I hit a pot hole, all bets are off! It doesn’t jump nearly as much as it did, but it still sends the Jeep on a different trajectory. Recovery is a b*tch. That’s what makes scares the
There are a handful of things that can cause it. The good news is that you've eliminated some of them with the replacements you've made, which helps narrow down what's left.
You mentioned tie rod...did you do anything with the drag link/pitman arm? Any significant angle at all to it is a major bumpsteer contributor. Ideally you want it as flat as you can get it (parallel to the ground). At 2.5" of lift it shouldn't be extreme, but I'd start there.
Ball joints would be the other thing I'd check, if you haven't already.
Do you have a sway bar? What air pressure are you running?
Just some things that come to mind...I'm sure other will chime in as well
1981cj7
Jeeper
Re: Death wobble vs bump steer
I did replace the drag link, it is brand new. That’s what I meant to say when I wrote control arm. I do have a sway bar and rag links. I did not replace them, but I did install new bushings. The ball joints seemed fine to me, so I have not touched them. I actually have no idea what air pressure the tires have. I’ve had the Jeep since mid June, and never thought of it got around to checking them. I will and let you know. Thanks
I did replace the drag link, it is brand new. That’s what I meant to say when I wrote control arm. I do have a sway bar and rag links. I did not replace them, but I did install new bushings. The ball joints seemed fine to me, so I have not touched them. I actually have no idea what air pressure the tires have. I’ve had the Jeep since mid June, and never thought of it got around to checking them. I will and let you know. Thanks
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Here's a pic showing what he's describing........ this instance is rather bad, but any angle will produce a bump steer - but the greater the angle, the greater the bump steer.....
This one is more better.....
Sent from the basement
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1981cj7
Jeeper
Thank you. Mine definitely looks like the first photo. I ordered a dropped pitman arm. Should be here next week. I did check the tires, and they are at 30psi. They are 31” Kelly Safari tires. The side wall says a max of 50psi. What would you recommend? And why? I am new to this, so I’m just trying to learn as much as I can. Thanks again for all the replies.
P.S. please ignore all the typos. I always forget to proofread :-)
P.S. please ignore all the typos. I always forget to proofread :-)
Belizean
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I run mine around 22-25 psi. Much higher than that and it's a ruff ride on pavement
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I ddon't have much experience with bump steer, but have more than I ever want with death wobble. I can see the left front whel from the cockpit, and when it goes into death wobble the tire edge begins an oscillation like out-of-balance, and in a second progresses to where the entire front of the jeep is shaking almost to destruction.
Three services corrected DW occurrence: new tierod ends, new bearings and ball joints, and the final and most effective was alignment and balance.
Regarding bump steer, I had so little clearance between tierods and underside mechinery that I did a tierod flip, boring parallel holes for tapered inserts. Workd=ed well, and I can finally accelerate past 50MPH without rough vibration of wheels.
The tierod flip should have been designed into our Jeeps, but we got what we god and are happy it is a Jeep, not sumptin else.
Three services corrected DW occurrence: new tierod ends, new bearings and ball joints, and the final and most effective was alignment and balance.
Regarding bump steer, I had so little clearance between tierods and underside mechinery that I did a tierod flip, boring parallel holes for tapered inserts. Workd=ed well, and I can finally accelerate past 50MPH without rough vibration of wheels.
The tierod flip should have been designed into our Jeeps, but we got what we god and are happy it is a Jeep, not sumptin else.
JeeperChris
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That sounds very useful. Did you need any special tools for that? Any videos on YouTube for it...etc?
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Gotta ream the knuckle to taper it on the top. Inserts go in the bottom. The kit I bought came with the reamer, but I'm pretty sure you can buy it separately.
It really helps...made all the difference in mine as opposed to just the dropped pitman alone
https://www.rockcrawler.com/techreports/bigdaddy_cj_tierod/index.asp