1990 Thomas front end popping and vibration

[comtb]

Hey there, I'm new here and in the process of my first conversion. I just recently bought a 1990 Thomas saf-t liner with the 5.9 paired with the at545.. (Definitely wishing it was a manual..) But anyways, it's non 4wd, so that makes a little less complication trying to diagnose this. When driving it on the highway right after I bought it, I had, and still have, a strong vibration as soon as I hit anything above 55mph, and the vibration now swaps sides. At first I thought out of balance wheel or blow hub oil, maybe a separated tread. Checked all of that out to no avail. Recently I've noticed a thunk and some shudder if I hit a bump, or if I turn fairly sharp. Thinking a dry or loose tie rod end, but it feels like those are tight. Maybe the pitman/steering linkage? I need to crawl under and hit all the grease zerks and torque all the bolts, but a preliminary visual inspection doesn't show anything obviously worn, broken, or loose. Any input would be greatly appreciated!

[charles_m]

Id check the kingpins, too

[cowlitzcoach]

It sounds like a broken frame rail to me.

Check between the spring hangers alongside the engine.

[comtb]

I gave the underside by the engine a look, didn't see any evidence of a broken frame rail, especially since I have a rear engine and vibrations are up front. Acting on some advice a friend gave me, I'll jack up the front end and have someone turn the wheel lock to lock while running to see if there's any play, binding or noises in anything

[EastCoastCB]

Originally Posted by charles_m

Id check the kingpins, too

THIS^ is a good idea

[comtb]

Originally Posted by EastCoastCB

THIS^ is a good idea

I've never checked kingpins, just ball joints... Same process? Will do an in detail visual inspection later today too.

[comtb]

Problemhas been resolved... Seems the original wheel weights were doing more harm than good, and the popping was cured by hitting the grease ports, which looked like they hadn't been hit in years.

[nat_ster]

Glad to hear it all worked out.

Nat