Death Wobble Woes

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swampy
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Death Wobble Woes

Post by swampy »

Fellas my M38A1 had incessant death wobble that starts
at 45-50m mph. New center link New wheel alignment, still no change. Tie rod ends are good too. Whats a man to do next? ~ Swampy~ :cry:
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Hawkshadow
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Post by Hawkshadow »

Do you have play in your steering wheel? Have you checked the king pin preload?
Jordan

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swampy
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Post by swampy »

Kingpin?..... hub swivel bearings?
Scott
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Hawkshadow
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Post by Hawkshadow »

Correct. If you remove your tie rod end from the hub and attach a luggage scale, it should take approximately 22-25 lbs (if I remember correctly) to move from side to side. If it's below that, you remove shims from that king pin to increase the preload which would reduce your shimmy (wobble).

Also, if you have excess slack at the wheel crawl under and inspect each link in the system while someone else turns back and forth through the slack at the wheel. It's possible that other worn parts, such as drag link and bellcrank, are giving you that slack and need a rebuild. This open space slack permits the wobble as the wheels can freely travel side to side without restriction.
Jordan

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scoutpilot
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Post by scoutpilot »

All good info. Also check that the tires/wheels are properly inflated and balanced.
Old fashioned service never goes out of style.
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oilleaker1
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Post by oilleaker1 »

Kunckle bearings and races with correct pre-load , bellcrank movement on the bearing, loose draglink adjustment, worn out sector and worm gear. Turn the steering wheel back and forth and look at all the movement. Check toe in adjustment. Sometimes the springs go flat and change the camber or castor (never can remember which it is) and that affects it also. The knuckle bearings are # 1 to check. They have a bad habit of wearing in a spot that allows them to be loose while all else is good. No way to fix it but replace. Drives you nuts. Jack up the front wheels and feel them by rocking top and bottom. John
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Post by skyjeep50 »

All good info above. One more thing to check and replace would be the steering knuckle seals - the strips of rubber that seal the axle ball. When you check king pin bearing preload the seals should not be installed but if the old seals are worn out, new seals will add even more resistance force reducing the tendency for death wobble. With the drag link disconnected and correct king pin bearing preload and new seals, turning the knuckles by hand is quite a push. Stops the slop before it wobbles.
1951 M38
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wesk
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Post by wesk »

This has been discussed many, many times on this site. Be sure to do a google search for: " Willysmjeeps death wobble ".

Lot of good points above but not all the things needed to check. Service manual with it's troubleshooting guide needs to be opened up and used.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

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timjuhl
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Death Wobble

Post by timjuhl »

I used to experience the occasional death wobble when I'd hit a bump the wrong way. After checking that everything was the way it was supposed to be I installed a "Steering Stabilizer" and haven't had a wiggle since. I painted it OD and fabricated a OD Fabric sleeve to fit over the boot so to the average person it looks like it belongs. If you plan to have your Jeep judged I'm sure the Jeep Police would take issue with it but for the person that just enjoys driving their Jeep it is a good choice.

Tim


https://www.summitracing.com/parts/ran- ... /model/cj5
Tim Juhl
1952 M38A1
1946 Aeronca L16A Army Liaison Aircraft
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