Front End Vibration

Another thought, don't know if International uses the same type of sliding shaft between the steering box and actual steering wheel shaft. KW uses this, one shaft slids inside the other, and when it is worn, will produce slack, noise, and vibration in the steering.

 

That's been replaced about a year ago with a heavier unit.

It may be in the track bar on the rear-rear axle. It was also replaced about a year ago but the rubber bushing has been pushed out again I see... bad design I guess.

 

Ok... I think I finally found the cause of the shake. A loose lower control rod on the front differential.


The shake has gotten worse lately so I went over everything today with a fine tooth comb. While I was crawling around under the rear end, I noticed a shiny spot in amongst all the grease where the control rod attaches to the spring perch (by the U-bolts). Lo and behold, there was a gap of at least an eighth inch between the nuts and the control rod bracket.

After trying unsuccessfully to tighten them myself, I ended up paying the high dollar to have an air wrench put to it. Unfortunately, one nut is seized and won't tighten... time for a new spring perch I think.

 

Great that you found it, sometimes things like that can be a real pain to root out.

 

Did you have time to wake Leroy up before you took this ride?I know he would'nt want to miss it.LOL

 

YEAH, LOL!
It was a hoot. Center point, not power steering in those days, and the spindle was digging into the asphalt while I was trying to shut it down. Pretty show of sparks too, as it was night.

 

I also have a severe front end shake in my 2003 peterbilt 379 and cannot seem to figure out what is going on without wasting what seems to be thousands of dollars. The Shake comes and goes but is pretty violant around 60mph to 65mph everytime with the ability to drive in and out of the shake. I have put brand new 10 tires all the way around, a new steering gear box, checked tie rod ends, drag link, and king pins and nothing seems to work. I know something has to give sooner or later before my dash comes apart! If anyone has any ideas of which way to go next I sure would appreciate it!!!! Another thing I cant figure out is why my steering wheel shake is minimal for as bad as my dashboard is shaking? Thanks to anyone who can help.

 

It still may be a drive tire. Usually a mis-mount. The shake is bad enough to cause the whole truck to shake and cause a minor steering shimmy. It comes and goes because the other drives and shocks are able to partially cancel it out. Also when you make a turn the tires will will change their orientation in relation to each other which will change the balancing dynamics.

 

Could be a centring bolt