Death wobble, KZJ78

[Lomoski]

Here is a couple pics,

This is 2007+ 70-series.

View attachment 1961628

This is a stock 92 Prado.

View attachment 1961629


Just change the panhard bushings out. Go test and see if it is still doing it. If it is we will troubleshoot it some more.

Cheers

Cheers! Panhard bushings are on order. Not the easiest to find here in Alberta so should have them within a week or so. They look pretty cracked so I'm imagining they are cooked. Appreciate your help.

Mostly only does it between 70 and 90 that's why I thought it was a wheel balance issue but a few reputable road force balances and it's still doing it/getting worse

Marc

 

[GTSSportCoupe]

I get some wobble around the same speeds if my tires are out of balance or if I'm running big tires (35"). I've found that basically anything loose in the front end can cause wobble. When I did kingpin bearings it really helped, and definitely the panhard bushing also. Check everything else also: wheel bearing pre-load, balljoints, radius arm bushings. When everything is tight and wheels well balanced, the issue should go away.

 

[Lomoski]

I get some wobble around the same speeds if my tires are out of balance or if I'm running big tires (35"). I've found that basically anything loose in the front end can cause wobble. When I did kingpin bearings it really helped, and definitely the panhard bushing also. Check everything else also: wheel bearing pre-load, balljoints, radius arm bushings. When everything is tight and wheels well balanced, the issue should go away.

Was the kingpin bearing job a big one? Something I should be able to handle? I'm going to check wheel bearing preload again today.

Cheers

 

[GTSSportCoupe]

Was the kingpin bearing job a big one? Something I should be able to handle? I'm going to check wheel bearing preload again today.

Cheers

It's basically part of a front axle/knuckle rebuild. You'll probably want to do wheel bearings, wiper seals, oil seals, all hub gaskets, hub brushes (if you're still electric), inspecting/repacking birfields, etc. all at the same time. Yes, it is a big job, but a necessary one. Probably well overdue if you've never had it done. Follow the factory repair manual carefully (RM183E) on this job. Kingpins are a fair amount of work as you have to replace the bearing races etc. too. Makes a big difference to the smoothness of the steering though. The kingpin bearing races usually are beaten oval and want the wheels to only steer in one direction. Once changed things feel so much better.

 

[Lomoski]

It's basically part of a front axle/knuckle rebuild. You'll probably want to do wheel bearings, wiper seals, oil seals, all hub gaskets, hub brushes (if you're still electric), inspecting/repacking birfields, etc. all at the same time. Yes, it is a big job, but a necessary one. Probably well overdue if you've never had it done. Follow the factory repair manual carefully (RM183E) on this job. Kingpins are a fair amount of work as you have to replace the bearing races etc. too. Makes a big difference to the smoothness of the steering though. The kingpin bearing races usually are beaten oval and want the wheels to only steer in one direction. Once changed things feel so much better.

Thanks,

I can get a knuckle rebuild kit from 4 wheel auto in Edmonton for about 400 including bearings and races. I've already done wheel bearings,braces and seals as well as brushes (still electric unfortunately) I'll add it to the list. I was hoping that bushings will at least take away most of the rattle and then I can deal with the kingpins when it's a bit warmer out. There seems to be an awful lot of SST required in the FSM. Can you do without?

Cheers

 

[GTSSportCoupe]

Thanks,

I can get a knuckle rebuild kit from 4 wheel auto in Edmonton for about 400 including bearings and races. I've already done wheel bearings,braces and seals as well as brushes (still electric unfortunately) I'll add it to the list. I was hoping that bushings will at least take away most of the rattle and then I can deal with the kingpins when it's a bit warmer out. There seems to be an awful lot of SST required in the FSM. Can you do without?

Cheers

I did the job DIY in my shop. Don't remember all the details, but I did have everything I needed. There are lots of videos on youtube of the job. It's basically the same for all the solid front axle cruisers.

 

[Lomoski]

I did the job DIY in my shop. Don't remember all the details, but I did have everything I needed. There are lots of videos on youtube of the job. It's basically the same for all the solid front axle cruisers.

Great, thanks. I'm sure I can do it myself just was wondering about tools. It's got almost 300k km on it and I don't think the PO was very good with greasing the ports.

Cheers

 

[Hugh Heifer]

Lt us know what you discover. Based on what I have read and my own experience, I would do a full knuckle rebuild - there are shims in there that may require the special tool to get the shimming right depending on the damage you may find the in the "king pin" aka trunions. Then go to the the pan hard bars and redo those ends.
Good luck. Should be easy to sort.

 

[Lomoski]

So I have had a chance to get under my truck. The left wheel bearing was just slightly loose, would just barely click side to side when pulled top and bottom. I also looked at my panhard rod and the bushings are definitely shot. The lower one allows the rod to move back and forth about 5 mm. I have ordered new bushings. The castle nut on the lower bushing is seized pretty tight, couldn't get it it break with a very long snipe. Has anyone had luck with heating that nut? Don't want to damage something. I've been spraying kroil on it every couple of days hoping it will loosen up.

Adjusting the wheel bearing definitely helped with the wobble, so hoping the bushings will solve the problem. Still need to do a trunion bearing replacement, but that will happen when money allows.


I'll keep you guys updated

 

[78pradobilly]

You need to add more preload to your knuckle bearings. Stock tires are 6lbs to 12lbs but for anything bigger than stock u need to go to around 15lbs of preload on the knuckles. This is done by subtracting shims