1998 Jeep Grand Cherokee experiences occasional " bad? wobble" when I hit a pot hole in the road. How do I fix it?

repair all the worn suspension parts and have a wheel alignment done

wobble of the steering is a wheel alignment problem regardless of having an alignment done
if your vehicle has a "live"front axle ( not independent suspension) the alignment is fixed to toe in toe out settings by the manufacturer
however spring sag and pivot pin(king pin bearings)wear alters that setting
There are devices available on the market that can be fitted by accredited suspension service shops that allow the alteration of the castor and camber settings ( you have a castor wobble) so talk with these shops and get ideas of what you can do
if it has independent suspension these settings can be easily set and should be set to around 1 to 1 1/2 degrees positive with toe in set to around 1/8 ti 1/4 "
a point that most alignment shops don't mention is that the rear end has to be aligned first so that the steering wheels are in the same "track" otherwise the front alignment is a waste if time as the vehicle will tend to run sideways down the road
it is an extra cost but well wort the expense when chasing a problem
next point --if the cv or "U" joints are failing then they will tend to have hard stops when steering and this will set of steering problems
lastly , big wide tyres are hard to align because of the amount of rubber on the road and to get the comprise between correct alignment and reduced tyre wear is hard to achieve

Sounds like 2-4 hi shift fork worn and synchro teeth not lining up to keep 4hi engaged, check fluid and pads on shift fork can be damaged.

take it to an alignment shop and ask them for a list of all the front suspension components which are beyond their service life. most likely it will be all of them, and the price to replace them all will exceed the value of the car. when they get old, they get play in them which rattle and clank when you hit a bump. the fact that you have a wobble and the noise means you are close to a dangerous failure.

Vibration from about 40-60 mph is usually attributed to wheel balancing, but the onset when you hit a bump seems to indicate play in the steering linkages (tie rods etc) or suspension members and stabiliser bar rubbers but you had that all checked out, that brings us back to the wheel balancing.

replace the crank angle sensor and this should cure your problem

Haha the death wobble replace the steering dampner or shock on the lower tortion bar of the suspension with an heavy duty upgraded one. Not a difficult repair check the tortion bar bushing for play. But the death wobble is caused by the steering shock. Seen it a lot fixes it every time. Hope the info helps rate it please.

most of the time, it's the trac bar bushing. if it's worn, you can death wobble over 40 mph. replace it with a polyurethane bushing.

Front shocks/struts may be shot...not dampening the blows from the street.
Also...very important... wheel balancing. Wheels that are out of balance will start bouncing like this too.
Also check alignment if it's only when you hit a chuck hole.

Ok, I figured out what was wrong with my 2005 Wrangler. By installing the coil spring spacers, I reduced the actual Caster angle of my front end. When I hit certain bumps at certain speeds, the front wheels would wobble back and forth violently as if i was pushing a bad shopping cart really fast. Anyhow, the dealer has replacement eccentric bolts to adjust the caster, but they didn’t stock them and they cost over $50.00. So, I opted to make my own off set washers to push the lower portion of the axle forward (gaining positive Caster). If you think this may help you, feel free to contact me at [email protected] .