KingPin Preload

[AndriesS]

This weekend I had a look at the kingpin bearings, They were all fitted with 0.5mm shims. I took them out, undid the tie rods etc and the hub was tighter, not close to the silly 1.5kg but not un turnable. I took the car for a test drive , no more wobble/shimmy at 100km/h,
I felt that removing 1 mm in total is a bit heavy and made some shims from 0.3mm gasket material . Even if it compresses slightly say to .25mm it should be fine. Could some of the real techs out there give me advise if this could be a problem?

I must say driving a Patrol without a wobble/shimmy at a key speeds is so much nicer!

[JG Shields]

Andries,

I am slightly worried. I am not aware of the "wobble" on my vehicle that you refer to. Di I only miss it or does the phenomenon only occur in some vehicles?

JG

[Herrie]

I know on the Safari/Patrol the problem normaly comes from loose nuts on the front wheelbearings.

[AndriesS]

The wobble I'm referring is very much like a wheel unbalance , I think most of the time we let it go as it is sort of acceptable - convince ourselves it is difficult to balance because of bigger wheels, wear patterns etc. Mine was at a very unfortunate speed to me annoying so I went through the death wobble list. As Herrie indicated sometimes the wheel bearings need to be tightened , some times the bushes are worn etc. I had mine rotated and balanced twice to zero , first time round made a huge difference, 2nd time round not at all.

Getting back to mine, it was speed dependent , I never felt that a road imperfection caused it , or made it worse. It never felt that I list control of it. I have never experienced a death wobble but they say you will know when you get it. There is a Jeep video and it is scary to see how the wheels shake form the outside.

In any case, the consensus is that the preload on the Patrol front end is very small and that the Toyota is almost twice . I'm still waiting for confirmation of it.

As a matter of interest, I started on the left wheel and with bot the tie rods disconnected and the top shim removed (0.5mm) the hub would still turn/slide to the left if left under it's on weight which in my opinion still means it is very "loose" . taking out 1mm(top and bottom shim) is a bit too much. The spec also indicates should be done without seals and driveshafts.

I think just like wheel bearings needing a check we should also check these bearings. They are normally last on the list , after damper, bushes etc. It's actually very easy even with th later big brakes you don't need to remove the brakes. )14mm socket and spanner is all you need) Checking the bearing is 4 bolt for each cap and one extra(12mm) to remove the bracket for the ABS sensor and 6 for the wheels. If you want to check the kingpin fro binding / looseness it's 2 more for the tie rods and a decent balljoint splitter.