Loose Steering After Hitting Bumps at Highway Speeds (sometimes)

[Levi]

Every once in a while (~50% of the time, maybe less) my steering will go loose for just a second or so after hitting a bump at highway speeds, say 55+. No shimmy, shake, etc., just a very brief vague feeling where there is play in the center of the steering wheel. I don't think I would say it is bump steer because it keeps going straight when it happens and I don't have to correct the steering.

I put a new steering box on about a year ago along with new TREs and radius arm bushings. The panhard rod bushings are about three years old but don't look bad. I also adjusted my swivel pin preload around the same time as I did the panhard rod bushings. I've checked the steering shaft joints and rubber and everything appears ok to me. I did notice that when I put the TREs on I had the steering damper a little off of level so I leveled it out and toed in just a bit which seems to have helped but it may just be in my head. At this time, I also pulled the damper off to check it and there were no loose spots in it and the bushings appeared good. However, I should mention that it is a Rancho 5550 damper if it matters (I know, I know but I was in a pinch and it was in stock).

I am going to recheck the steering shaft joints and make sure everything else is tight. Any suggestions or anything to search that I may have missed? I thought about checking my swivel pin preload but there is no shimmy so I don't know if this is the direction for me to go.

TIA

 

[discostew]

Your swivel housings are loose. In 98 they used a needle bearing on top that had a plastic cage instead of the regular old steel caged bearing they used for years. The name for the procedure that you need done is called steering enhancement or something like that. It involves setting the preload on the swivel housing by changing out some shims at the top of the housing. I would really leave that to a pro. expect to pay about 6 hours of labor and maybee a couple hundred in parts.

 

[Levi]

Thanks for the suggestion. I was thinking it might be the swivel pin preload as it has been a few years since I've done it; I will have to check it when the weather clears.

I hope you didn't pay for six hours labor and for parts to have this done. I know it didn't take me six hours the last time and there shouldn't be any parts charges if you don't need new swivel pins as you are just removing shims.

 

[Mike Cox]

Might want to think simple also.. the steering dampener could be gettting old... just saying.

 

[discostew]

For six hours and 200 dollars worth of parts I would reseal the housings complete,replace that plastic caged bearing with the steel caged one and set it all up correctly. When you set the preload did you have the swivel seal out of the housing ? warranty time for this job was over 4 hours if I remember correctly. But for sure if you go back in there get rid og that plastic bearing,it was a huge problem on 98 trucks,then they went back tothe other bearing for the last year 99. so get your high tech fish scale out and get started.

 

[Levi]

When I did it before I adjusted the preload per this guide http://www.fag.hiof.no/~frodehaa/swivelpinpreload.htm so I didn't have the seal out. I see now that what you are referring to is a little more involved. Thanks for letting me know about the plastic caged bearing, I hadn't read about that in any of my searches.

I will have to dig out my scale and check it out when it isn't -1 outside, my garage is quite chilly right now.

 

[lambo]

definetly not the steering dampener, which is only there to recoil backlash from tires hitting stuff while thrashing though the trail. i had same issue you had. ended up being the pitman arm nut was loose

 

[discostew]

I think I should have read your poost a little better before I jumped to that diag. There are a lot more simple possibilities to what your feeling. I think you should look for play in your steering shaft and maybe chk out some of the bushings and links at the rear of the truck also. If the rear is loose it can be kind of hard to pinpoint.

 

[Levi]

Rear bushings were already on my to do list. I plan on rechecking the steering shaft and pitman arm. How much play is acceptable in the steering shaft?

Thanks for all of the help.

 

[Paul Grant]

If you can get the truck up in the air and get under it here is what I would check.
1) Examine all TRE's, all nuts and bolts as they relate to the front steering and suspension.
2) Check the Panhard Rod bushings (frequent culprit) and front radius arm bushings.
3) Check swivel preload. (Most involved but common fault)

 

[capri_auto]

Nevermind, probably damper

 

[Paul Grant]

Oh, and as far as the steering damper is concerned, it doesn't cause problems. It merely conceals them. A properly set up front end does not NEED a steering damper at all. It is a convenience. Series Rovers didn't have luxuries of this sort until the 1970's!