finally got to drive the ZJ around today, and I have some bad death wobble over 25 mph. The kingpins were both completely re-done, alighnment looks good, tires arent balanced but seem very good at speeds under 25 mph, pinion angle is turned up perfectly to the drive shaft, not running a steering stablizer yet. tires are bias ply h1's 36x12.50. what should i look at to cure this problem?

castor angle, and or shimming the kingpin

Its the KP shimmed correctly ?

also try tightening the meshload on the steering gear box. i had the same problem and that fixed it.

How can I tell if the KP is shimmed correctly? I am running the HD WFO arms that eliminates the spring and just uses shims. I made sure the knuckles were tight, but I do have some more shims. Should I put them all in? Maybe I'll try that and tightening up that gear box. I think I'll try a steering stabilizer too.

I also have WFO HD arms on my D60, I did NOT need all the shims, but that will depend on the amount of wear in the king pin parts (yers are new, not much wear?) basically drop the tie rod and steer the wheels by hand to see if u have enough preload. Beyond that recheck ur caster angle, if ur less than 6*-8* ur gonna have some issues. A steering stabilizer is a band-ade not a fix, think of the stabilizer and something that keeps the steering wheel from being ripped out of ur hands when u hit a trail obstical, not something to keep ur tires straight on the road

Check your track bar. I thought my kingpins were bad too, bought a steering stabilizer, aligned it several times, blah blah and my damn trackbar was just loose.

There are a lot of things that can cause what you got. I had it bad. So bad that at 30 MPH I thought it would rip my frame apart.

I ended up doing a couple things that helped.
I set the tow in a little more than normal, but with the big tires the drive thrust made it fine.

I think that using washers on my kingpin springs helped the most though. There is a thread about what washers to use and what thickness's to start out with. I think I ended up using a washer that was about 3/16th thick on both sides and I have not had any wabble since.

JOSH

Yea at 25-30mph any little bump in the road and it feels like the PS box is gonna get split.

Everything is brand new. KP's, Hi steer arms, TR, DL, TRE's... I looked again today, and my caster seems to be wayyy off, so I'll try and dial that in tomorrow and see if that helps any. I am betting it will.

As for the SS, I havent run anything bigger than 35" radials before, so I didnt know how it would ride with all that extra tire and heavy ass H1 wheel (welded rebar in the lip) would/should feel at speed. Im sure it would help, but def. wouldnt cure the DW I have now. Thanks for all the help guys.

Scott, when I first got my D60 in my YJ I had the knucklespretty damn tight for preload (took a decent twist to turn them). Went for a drive and boom had the wobble, pulled it back in the shop and checked the knuckle preload and it was pretty damn loose. Added some more shims, and it seems to have gone away. At TDR though my drivers side has seemed to loosen up again. I think some of it is the gasket compressing, and everything "settling". Check the nuts for the arms too or rotating the tires front to rear.

Ok, I'll look into that too Dave. Can shimming it too much cause any real damage, or just wear out the KP and stress the steering box more?

shimming mine w/ one decent size washer completely solved my wobble issues...

I shimmed it with all four shims on each side. It helped a ton, but on certain bumps in the road I can still get it. I checked caster to be between 7-7.5* and toe in to be about 1/4". I set more toe in because at 1/8" the steering wondered and didnt feel like it tracked as well. Oh and I also tightened up the steering box gear, which helped as well. I think I'll try balancing the tires and going to hydro assist to help.

shimming mine w/ one decent size washer completely solved my wobble issues...