front end wobble when braking into corners

[giddyup_fatboy]

I have read all the forums on front end shimmy & death wobble in the Bible (BTW Love the bible.Bloody good job Wendle & good on ya to the fella who suggested it !) but none as yet have described the same symptoms as the GQ has developed.

I get a mean front end wobble when braking into corners & about a inch movement of the steering wheel from left to right while applying pressure to the peddle.It seems to be getting worse over the last 2-3 months .
The 80km a hour wobble that everyone else seems to refer to is only very minor in my GQ & appears to be less that the inlaws stock bogger GQ with full road trim.

The car is a 92 GQ LWB TD 4.2 Modified September 2003
Big balls 4inch kit ,heavy spring ,Racho 5000’s front set to 3-4 & 9000’s rear set from 6-8
5 degree castor correction plates
Return to centre 4way steering dampener
33 BFG mtrs on sunraisure
2inch body lift
no rear sway bar

The car has been modified now for about 10 months so everything is fairly new & the car so far has been great . Trip up the Cape & no damage or problems apart from the usual squeeks that have developed after all the F#&king corrigations.

A recent trip to Tassie for the nav run high lighted how bad the problem really is. With a 99% increase in corners (farkin Tasmanians) it wasn’t hard to see how bad the problem is breaking in the corner / mid corner was inevitable . At home its is the commuter so the majority of roads are the suburban norm. I don’t need to use the brakes leading into or mid corner so much so it isn’t high lighted at home .

The car gets regular wheel alignment & balance & has done about 25k since I purchased it .

Things I have checked

Panhard rods, tightened retaining nuts
Wheel bearings, checked & retightened
Tyre rotation front to back & x
Brake Rotors ( 1 small hot spot on 1 disk) ???
Slop in bushes ,none evident
Slop in ball joints ,none evident


I assume it is going to be slop in a bush or a loose joint & as yet nothing has been replaced until a defective item can be found..
Still cant find the problem & shimmy is still evident ..

After all that ………….anyone got any ideas on what the fark is causing it ??????????

Neil
VAT team 1

[bazzle]

My guess is hard spot on a rotor.
If it is that replace with slotted DBAs.
Fairly priced., improve overall performance.

Bazzle

[Dirty Dave]

My guess is hard spot on a rotor.
If it is that replace with slotted DBAs.
Fairly priced., improve overall performance.

Bazzle

I wit bazzle and done the same myself....

Dirty D

[giddyup_fatboy]

Thanks guys for the advice.
I did notice on the way home from work this morning i could place small bit of input into the steering wheel just to take it past the mid point slop on a straigh bit of road you got a minor but similar sensation of feedback on the steering wheel .... WTF??? hhmmmm

Baz
Your local to my area .. who did you get the rotors from ??

[awill4x4]

Another thing to check is the brake caliper slides. I had similar problem and it turned out to be a seized slide bolt so when the brakes were applied it was trying to push the brake rotor from one side of the disc only. Another symptom of this is a spongy brake pedal which goes hard if the brake line on the offending side is clamped off with vice grips.
One thing to be aware of if it is the GQ Patrol twin piston caliper and you need a new slide bolt. That in Nissans own schematic diagram the dealers use to order them, the diagram is actually upside down and if you order the top slide bolt you get sent the lower one instead. It took us nearly 3 days of of contacting Nissan till someone actually realised what the problem was.
Regards Andrew.

[bazzle]

Bursons.

Ensure wheel bearings tight too. Even though when fitting new disks bearings will be inspected etc.

Bazzle

[embryo]

i have a mate who encountered the same problem and after replacing a lot of things discovered that his steering box bolts were loose. and as for the sloted rotors i dont think the price justifys the little improvement in braking

[bazzle]

Quote:
and as for the sloted rotors i dont think the price justifys the little improvement in braking

The little improvement in braking can be the difference between being 2 metres into someons boot or stopping at their bumper!!

Also made 35s pass brake test at engineers.
Have you tried slotted?

Bazzle

[BIG GQ]

I'm with Bazzle.

If you hadn't said it was only under brakes and into a corner I would have said front pan hard rod nuts (IWOULD DEFINATELY CHECK THESE though as you said they have not been checked) but yes I agree check wheel bearings FOR SURE but DO NOT put excessive pre load on em and check rotors.

As for Wood duck (embryo) and "sloted rotors i dont think the price justifys the little improvement in braking" - WTF Are you aware of what you just typed Have you driven with them

Cheers
Linc

[embryo]

i am a mechanic, and so have driven on them, fitted them and not replaced some of them again for the customer because they thought the cost didnt justify the improvement and reduced life of the rotor, however each to their own and if that is whats needed 4 an engineers then so be it, if you really want to stop better as well as the slotted and drilled rotors a caliper upgrade would be well worth it. this is just my opinion and what i found works for me and my driving style.