Shimmy at 35 mph & 60mph

[mackdaddytruckfixer]

New to this form but an old hand. I have a 90 RD 688 and the front end like it is jumping up and down at 35. I inspected the front end everything looks good. Put new rubber on no change. I hate throwing parts at it without a good idea what I'm looking at. Really I think I should replace rims next. It is a 20k front on 385 floats. Any help would be great.  Vibration in steering wheel at 60 +

[JerryB]

I had the same prob.  Installed new kingpins didn't help.  3 point alignment didn't help.  Rotated tires no help.

 

 

[mackdaddytruckfixer]

I have spokes on the back inside rim was bent 90% of it is gone I will keep you informed what I find. 

[mackdaddytruckfixer]

Had a new drive shaft made old one had a decent sized dent and one of the ujoints was locked up. Wow what a difference that made. I have always shook my drive line down everytime I greased it and no movement at all. Seen the small dent took it off to a trusted drive line company and he did all repairs but that one cost a G.