Newbie's Knuckle Question (1 Viewer)

[Robin Hou]

I have my 1996 FZJ80 for a year now, but only have been driving it for the last 6 months for around 5,000 miles. It is still a new to me truck and I am still learning to run and maintain it correctly.

My front end developed a noise last night. When I was driving at parking lot speed and turn, 8 out 10 times, there were faint clunking noise from the right front. This morning I jacked up front wheels, and felt movement when I held wheels/tires at 12 and 6 o'clock positions. There was no movement if I held at 3 and 9 o'clock positions. Both side felt about the same as the right/noisy side did not have significant more movement.

My service records show knuckle service a few years ago but no indication if knuckle bearings were replaced. So I am guessing my knuckle bearings need replacement.

Is my above diagnosis reasonable? Is there other check I should do before I tear my knuckles apart?

Assuming I need to overhaul my knuckles using ready made kit (i.e. Marlin Crawler, ...), what other items/service should I perform while I am in there? Wheel bearings, birfield joints, ...?

Thanks in advance for all comments.

 

[sunrk]

If you get play with the wheel held vertically that is normally indicating play/problems with the wheel bearings. If you get play with the wheel held diagonally that will normally indicate play or problems with the kingpin/knuckle bearings.

If you have maintained the grease in the swivel hubs as much as possible (noting it is almost impossible to grease the top kingpin/knuckle bearing without disassembly of the hubs) jack up and support the front axle and double check the freeplay you feel with both front wheels off the ground.

If you confirm some with either or both wheels wiggled vertically, checking the wheel bearing adjustment is the easiest thing to do next. There is a specific process in the toyota fsm for setting front wheel bearing pre-load but that is really not applicable when just re-adjusting the bearings in-situ without having the hubs off to fully re-grease the bearings and fit new seals or when replacing the wheel bearings.

If you can wiggle either or both front wheels diagonally, then you might have an issue with the kingpin/knuckle bearings. Taking everything apart is a very messy job and takes a fair amount of time if doing it all by yourself but it's better to take the time and do a job properly rather than rush it.

 

[-Spike-]

I have my 1996 FZJ80 for a year now, but only have been driving it for the last 6 months for around 5,000 miles. It is still a new to me truck and I am still learning to run and maintain it correctly.

My front end developed a noise last night. When I was driving at parking lot speed and turn, 8 out 10 times, there were faint clunking noise from the right front. This morning I jacked up front wheels, and felt movement when I held wheels/tires at 12 and 6 o'clock positions. There was no movement if I held at 3 and 9 o'clock positions. Both side felt about the same as the right/noisy side did not have significant more movement.

My service records show knuckle service a few years ago but no indication if knuckle bearings were replaced. So I am guessing my knuckle bearings need replacement.

Is my above diagnosis reasonable? Is there other check I should do before I tear my knuckles apart?

Assuming I need to overhaul my knuckles using ready made kit (i.e. Marlin Crawler, ...), what other items/service should I perform while I am in there? Wheel bearings, birfield joints, ...?

Thanks in advance for all comments.

I hate to argue with anyone but play when pushing at 6 and 12 o'clock can be either trunnion (knuckle) bearings and/or wheel bearings, while play at 3 and 9 can be wheel bearings and/or ball joints (tie rod ends). I've never tried it, but checking diagonally probably brings everything into play. The best way to figure out if your trunnion bearings are shot is to take it apart and look, the second best way is to check and probably tighten your wheel bearings, then do the 6-12 test. If you have movement with tight wheel bearings, that is most likely the trunnion bearings.

In any case, sounds like a front axle overhaul is what you need. I recommend the kit from Cruiser Outfitters, or OEM. A lot of kits come with substandard axle seals. You should check everything, as it will all be apart aside from the differential. Include brakes and related components (pads, calipers, rotors, etc.).