Death Wobble Weirdness

[Black & Tan TJ]

The time I was stricken with the DW it turned out to be the pitman arm end of the draglink. It had movement up/down and the right hit in the road there it went. Found it by the old have someone turn the wheel back and forth violently and look for unusual movement. You good at this stuff, you'll find it. Pictures would be cool.

[Mike]

Success! Well, not quite...

Okay, pictures it is!

Round two.

I got the bolt needed (as already posted), but I still needed to get the remaining piece of bolt out of the track bar. Today, I rigged up my come-a-long to align the bolt with the hole. It only took a few clicks after it was tight to get the hole lined up. I used a pry bar to push the bolt as far as I could out of the hole. The problem was that it was not long enough to push out of the hole:



I could push against the inside end with my finger, but I wasn't strong enough to make it move. I needed something that was bent finger shaped, but a little smaller in diameter and a whole lot stronger. I found a scrap of 1/4" share stock and made the appropriate bends:



The makeshift tool worked perfectly!:



ViceGrips do the rest of the work:



Finally, the old bolt is free! Now I need to put a new bolt in. I stripped out the OME nut years ago. But I still kept the mounting in case I wanted to try to reuse it. Well, this seemed like the best time to try.

I searched around and finally found the OME mount:


I started cutting the pinch points with an angle grinder with a cutting blade, but I found that the tool was just too large for the job. After switching to a Dremel tool, I was able to free the stripped nut:



I took the flanged nut that I bought at Ace Hardware and tack welded it onto the OME mount:



Since everything was so nicely lined up with the come-a-long, I slid in the new bolt easily and tightened the whole thing down. I now have a nice shiny bolt in place:



I then went through a list of items that can lead to Death Wobble. I found three bolts slightly loose: Upper control arm, both lower control arms.

Additionally, I checked the toe-in and found that it was significantly off to the in side. This was adjusted to an 1/8 of an inch.

So now I am expecting the problem to be solved. I take Mr. Green for a drive and it is super smooth up to 65 MPH. Then a very fast, constant vibration shakes the Jeep. Unfortunately, it was dark by this time, so I couldn't see if it was shaking the driver's side tire. It feels like it is coming from the passenger side, so tomorrow I will switch out the tire and see if it is just out of balance.

Keep some fingers crossed for me...

[Tumbleweed13]

Great explination. Its good to see that saving old parts actually comes in handy. I have a bunch of orig jeep parts that I swear, I'm gonna need some day.

[aw12345]

Okay, pictures it is!

Round two.

I got the bolt needed (as already posted), but I still needed to get the remaining piece of bolt out of the track bar. Today, I rigged up my come-a-long to align the bolt with the hole. It only took a few clicks after it was tight to get the hole lined up. I used a pry bar to push the bolt as far as I could out of the hole. The problem was that it was not long enough to push out of the hole:



I could push against the inside end with my finger, but I wasn't strong enough to make it move. I needed something that was bent finger shaped, but a little smaller in diameter and a whole lot stronger. I found a scrap of 1/4" share stock and made the appropriate bends:



The makeshift tool worked perfectly!:



ViceGrips do the rest of the work:



Finally, the old bolt is free! Now I need to put a new bolt in. I stripped out the OME nut years ago. But I still kept the mounting in case I wanted to try to reuse it. Well, this seemed like the best time to try.

I searched around and finally found the OME mount:


I started cutting the pinch points with an angle grinder with a cutting blade, but I found that the tool was just too large for the job. After switching to a Dremel tool, I was able to free the stripped nut:



I took the flanged nut that I bought at Ace Hardware and tack welded it onto the OME mount:



Since everything was so nicely lined up with the come-a-long, I slid in the new bolt easily and tightened the whole thing down. I now have a nice shiny bolt in place:



I then went through a list of items that can lead to Death Wobble. I found three bolts slightly loose: Upper control arm, both lower control arms.

Additionally, I checked the toe-in and found that it was significantly off to the in side. This was adjusted to an 1/8 of an inch.

So now I am expecting the problem to be solved. I take Mr. Green for a drive and it is super smooth up to 65 MPH. Then a very fast, constant vibration shakes the Jeep. Unfortunately, it was dark by this time, so I couldn't see if it was shaking the driver's side tire. It feels like it is coming from the passenger side, so tomorrow I will switch out the tire and see if it is just out of balance.

Keep some fingers crossed for me...

If it continues you can borrow the front tires from my yellow one to see if resolves it. They are not balanced at all but the Yellow beastie has absolutely no vibes in the front end. That's one of the things that's good aboutKM 2's they seem to balance with very little weight

[mkjeepers]

Mike another thing to consider with high speed vibration is one or both of the driveshafts being bent or out of balance. My front shaft is a little out of balance and I get a vibration at 62mph and it goes away at 65+mph. I discovered this by rasing the Jeep and putting it in 4wd. The front DS was visably out of round. I disconnected it and drove it on the freway and the vibration was nearly gone. Maybe the rear is out a little also.

[aw12345]

Mike another thing to consider with high speed vibration is one or both of the driveshafts being bent or out of balance. My front shaft is a little out of balance and I get a vibration at 62mph and it goes away at 65+mph. I discovered this by rasing the Jeep and putting it in 4wd. The front DS was visably out of round. I disconnected it and drove it on the freway and the vibration was nearly gone. Maybe the rear is out a little also.

It would be vibration but you would not feel it in the steering wheel. still the way to find out is to eliminate one thing after the other till the problem is resolved

[Mike]

If it continues you can borrow the front tires from my yellow one to see if resolves it. They are not balanced at all but the Yellow beastie has absolutely no vibes in the front end. That's one of the things that's good aboutKM 2's they seem to balance with very little weight

I've heard that before about the KM2s. I am leaning towards getting a set when the MTRs die. The Kevlar MTRs that I have take a lot of weight to balance.

Mike another thing to consider with high speed vibration is one or both of the driveshafts being bent or out of balance. My front shaft is a little out of balance and I get a vibration at 62mph and it goes away at 65+mph. I discovered this by rasing the Jeep and putting it in 4wd. The front DS was visably out of round. I disconnected it and drove it on the freway and the vibration was nearly gone. Maybe the rear is out a little also.

You know, there was a point on Mottino that I thought that I might have gotten close to the front driveshaft. I will check it out tonight. But like Art said, it doesn't come from all over like a driveshaft tends to vibrate. I mainly feel it in the wheel and seat.

[aw12345]

Still think the MTR is a better tire than THE km2'S, other that not needing a lot of balancing, they are loud as hell on the street, aren't a very good rock tire. I loved my little old whitewall retro MTR's, they took a lot of abuse a lot more so then the MTZ's I had which were a lot quieter than the KM2's.

[Mike]

Still think the MTR is a better tire than THE km2'S, other that not needing a lot of balancing, they are loud as hell on the street, aren't a very good rock tire. I loved my little old whitewall retro MTR's, they took a lot of abuse a lot more so then the MTZ's I had which were a lot quieter than the KM2's.

I do have to say that the new MTRs are a quieter tire than most of it's breed.

Well, after driving it in the daylight, I still have the wobble. It just happens at a higher speed now.

[Black & Tan TJ]

It just happens at a higher speed now.

Cool but the speed limit is 65 ish

Yeah those newer MTR are pretty quiet even after many heat cycles and wear there still not too bad

[Mike]

Today I started by checking the toe-in again. It was toe-out by 1/4 inch! What changed? The last time that I had a wandering toe, a unit bearing was bad. So I pulled both of the unit bearings today and they both seem solid. Just for kicks, I swapped the sides to see if anything changed.

I took a pry bar to all of the bushings, ball joints, and all contacts to the steering and axles. Everything seems in good order.

While it was up on the jack stands, I re-set the toe in. Maybe the fact that I originally set the toe-in on a sloped concrete driveway caused the shift once it was on level ground. I also disconnected the stabilizer and tested it and it is still strong.

I took it for a drive and no change. Still starts wobbling at about 55. I did notice that the steering wheel does NOT shake. Almost like it is not steering related. More weirdness!

I noticed a repetitive 'ticking' sound that comes and goes at slow speed. Almost like it is related to the turn of the tire. It doesn't hang around for very long at a time, so it has been tough to locate a source.

I think that next step is to attach the GoPro under the Jeep and see what is happening while driving.

[DanPartsman]

I'm not sure if you have looked into this but I thought I would throw this in since I had a similar problem with my '78 CJ. After 2 years of forum searching, replacing all the front end components, wheels, tires, brakes, drive shafts and axle components I ran across a forum post that had the answer.

Smart people say that theoretically the angle of the tie rod (connection between the pitman arm and steering knuckle) should aproximate the angle of the drag link (they should be parallel). But this one post I found said that the more important issue is that the lowered pitman arm used with Jeep lift kits creates instability in the steering geometry. I had a lowered pitman arm from my 4" lift install, so I thought - what the heck, might as well try. I just replace the pitman arm from the lift kit with the stock one and presto - no more DW and finally a fun driving experience!

[aw12345]

Seems to me tire balance would be a good thing to rule out. Driving without the front drive shaft not a bad idea either.
Checking u joints in the axle shafts is an option clicking could be as simple as a brake pad kinda bouncing around in the caliper, easy to diagnose, when it clicks slightly apply the brakes if it goes away, you found the culprit of that.

[Mike]

I appreciate the ideas. I have been testing all of them, but still no luck. Russ Chung suggested something that I thought was going to be the trick. Check the frame and track bar mount for cracks. Checked it and it is solid.

I took video and put together this video. Check it out, the steering and track seem to be solid, but the tires are going crazy. Could a bent axle housing be doing this?

http://www.youtube.com/watch?v=0WYCbmaw_q0

[aw12345]

Tire inbalance, bend rim or axle U joint. Start with swapping tires is easiest and go from there. Or put the the Jeep on 4 jackstands under the axles, stick it in 4 hi, have Sharon drive it to where it start misbehaving and see if you can get a better idea of what is going on