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NEKAF M38A1
Occasionally when i hit a bump in the road with the front wheels, the front wheels start to oscilate in a sideways motion which also shakes the steering wheel. Disappears after I slow down. Everything seems tight underneath. Jeep cruises fine at all speeds otherwise.
Any ideas?

Check your wheel bearings, I had the same problem... I would go over 30 MPH and the whole front end would shake and shimmy...

Found the fron wheel bearings loose, the PO had not locked the lock nut washer and they had worked loose about a half to 3/4 of a turn...

Hope this helps...

Check and adjust the king pin bearings.

Thanks, will do.

The primary cause is the King pin bearings are probably loose. They may be worn out or just need adjustment. When set properly, the front wheels are rather stiff to move side to side. This stiffness is actually measured. Check the Maintenance manuals or other sources for the proceedure. One description I like is on Novak's website.

http://www.novak-adapt.com/knowledge/st ... repair.htm

It's probably time to check all the steerning linkages as well.

Will look at the bearings first, then the king pins. Thanks again.

do a search on "death wobble" on the various jeep sites. You will find plenty of reading material to help you nail down the problem.

Tom

I had this exact death wobble for a couple years. I tightened almost everything up, bearings, rods, joints. Got new tires, needed them anyway. Got them professionally balanced. Stil the death wobble!

One day I was under the vehicle and felt the steering gear box was loose. I could not see or get to it unless I took off the fender, which I did. I found the bolts mangled and the nuts mushroomed, replaced them with lock washers and the death wobble was totally gone. I would call it one of the top... twenty happy events of my life, as my M38 became a total pleasure, my wife would ride in it again, or let the kids, and I never had to worry about shaking apart 50 miles from nowhere in a rainstorm. = )

GOOD LUCK and I hope you resolve this nightmare!

Leo wrote:
Occasionally when i hit a bump in the road with the front wheels, the front wheels start to oscilate in a sideways motion which also shakes the steering wheel. Disappears after I slow down.

I've experienced this years ago on a '53 Ford pickup with too much toe-in. The error didn't seem like much just looking at the numbers, but correcting it to the spec value completely eliminated the problem.

On the ground have someone rock the steering wheel side to side & check for wear on all steering components for movement related to security or wear.

Jack both front wheels off the floor & place vehicle on stands.
Grab the top & bottom of each wheel in turn & try to rock in & out top & bottom.

You will probably find movement....but what is this movement indicating?

Loose wheel bearings or king pin bearings.

How do establish which?

1. Have someone apply the brakes & if the movement is gone the wheel bearings are loose.
If ONLY part of the movement is gone or the movement is unaltered that remaining movement indicates:
2. the king pin bearings are worn or loose needing service.

While in the air you can again check for other component issues by rocking the wheels to the front & rear rather than top & bottom.
Any wear or slop is quite noticeable & needs correction.

Very helpful John, I'm going over to a friend tomorrow who has all the gear, and will test everything out.
Hope its not the King Pins, i have to import all the parts from the US since I'm in the UK and finding someone locally who knows jeeps is difficult. The nearest is in Kent a two hours drive away.

No biggie king pin bearings from any bearing supply place as are hub bearings & seals