DEATH WOBBLE WHEN BRAKING

[KOOS BEST]

Hi , I have just returned from a trip to the Drakensberg.
I have picked up a little trouble, I see the Ozzies call it death wobble.

As soon as I brake (lightly) down a mountainpass or incline my wheels start to wobble, between about 85 -110km/h.It only goes away if I reduce speed or brake very hard.
On the Oz site it seems to be common with solid front suspension vehicles.

They (different chaps)recommend the following.
Balance wheels
Check Alignment
Skim brake disc
Fit New panhard bushes ???(ANY MORE INFO )
Replace steering shock
Adjust and shim king pin bearings ???? (ANY MORE INFO)

Anybody out there with the same problem, and how did you sort it out?

PSE PSE PSE HELP I AM DESPERATE!!!

[G-MAN]

Hi Koos. Have a look at your panhard rod bushes first, then king pins.Also check the obvious first, tie rods etc. Lets hope it's something silly...

[Herrie]

Also check the nuts on the front wheel bearings!

[KOOS BEST]

Thx , guys will try and do it this weekend.
Koos

[tour de frans]

HI Koos
I had the same problem on a friend's 4.8.The steering shock's bushes were out.Also Did you correct the caster after the suspention lift.
Rdgs Frans

[Ratau]

Koos

Also check the brake disk; it could develop a glazed spot. These spots are extremely hard and that result in uneven wear with high spots.
When worked hard and got very hot it could pull skew or bend.

My Isuzu got the glazed spot problem, I had the disks skimmed, it’s better now but I think it’s time to replace the disks.
It feels like manual ABS.

[KOOS BEST]

Once again thx to all the contributions. I have just read through the workshop manual and will do all that.
ie. Panhard rod bushes , wheel bearings, king pins and brake disc.
Will try and post pics.
Koos

[Ross]

Ja, have also been struggling with this...

On my van its most pronounced when running the A/T Geolanders that came with the vehicle (at speeds between 95 - 110), and more or less goes away when I run the 33" MT`s, so I take it that even though the A/T`s have been balanced twice, that they are part of the problem. I guess one obvious response is "don`t run the geolanders", but since I do a fair amount of commuting with the Patrol, it seems a shame to chew up the MT`s on tar, so I`m trying to keep them for playing and overlanding only.

So far I have replaced tie rod ends, replaced the drag link, fitted the castor correction kit, and had the pre-load on the front bearings adjusted (there was slight play).

The panhard rod bushes feel okay, but I was going to replace them anyway just to be sure. Surprise surprise.....Nissan SA don`t sell the panhard bushes, only a complete new panhard rod for some crazy price Anyone know of a local source of aftermarket panhard bushes????

I have also read about the adjustment/shimming of the kingpins, but have never been able to fully understand how this is done, or how one would determine whether it needs to be done. Can anyone shed any light on this???

[KOOS BEST]

Hi , today with the help of two mechanics we checked my Troll on a hoist.
1) Panhard rod and other bushes(tie rods etc.), they checked with a pinch bar, no play at all was found on the rod bushes, they seem to be in good (excellent)state.The one guy owes a Cruiser and his panhard rod bushes are stuffed.Keeping in mind have I have only done 20 000km since I acquired this vehicle, I can say that the previous owners never even went off the tar, according to the state of the under carriage.
I have found a bussiness in R/Bay that said I can take it off , and he cast new poly bushes in the Panhardrod or makes it up to size. So if anybody have bush problems there is Linsay Casting in R/Bay that can help.
2)Steering, found excessive play , so took up play and adjusted.
2) Wheel bearings, lot of play on left, had to tighten and adjust.
3) Wheel balancing and alignment, got it done today in Empangeni by TWT

Driving back the wobble was gone , but as soon as I apply light brakes with left foot and keep power I can a feel a slight wobble in steering, so according to Oz site that indicates I need to skim my disc as well. This I wil do this week coming.Other wise she's much smoother and above 140 km/h she feels stable.

So if I look at my case it was the play on bearings, steering and the wheel balancing .
Ross, so you dont have to replace the Panhard rod, I can source you bushes locally, or look for a Polyurethane and rubber casting bussiness in Cpt, they will be able to help you out.
Koos

[Patrol4.8]

Driving back the wobble was gone , but as soon as I apply light brakes with left foot and keep power I can a feel a slight wobble in steering, so according to Oz site that indicates I need to skim my disc as well. This I wil do this week coming.

Het jy al jou discs laat skim Koos? Indien wel het dit gewerk?
Ek het myne verlede jaar laat skim en die wobble was vir 'n rukkie weg, maar dit het na 5000km weer begin agv slytasie tussen die glazed gedeeltes op die disc net soos Ratau dit beskryf. Ek dink Nissan se discs is swak want meeste Nissans insluitend my 2 plaas bakkies het hierdie probleem.
Pierre(Freakazoid) het genoem dat ek DBA(Disc Brake Australia) moet kontak vir goeie discs. Hulle voorsien die gewone sowel as slotted en cross drilled discs.
Wat se julle slim manne, dit lyk of die slotted weergawe vinnig afkoel vir die van ons wat swaar waens teen berge afsleep. Lyk ook baie cool Ek wag nou vir pryse vanaf DBA dan laat weet ek vir julle.

Hier kies jy jou voertuig
http://www.dba.com.au/product_search_dev.php

Slotting vs cross drilling
http://www.dba.com.au/2006/QnA/DBA_QnA_9.asp