Upper control arms on VN Diff aftermarket or factory?

[Bz Kn33z]

Has any1 every seen the upper control arms on a live axel VN V6 diff how they are kinda small and flimsy, i seen a vn at the wreckers that had 2inch squar upper controll arms with new bushes, would this make the handleing better on the old vn?

[Pub247]

You talking about trailing arms i'm guessing? their main purpose is to stop forward and back movement of the diff if I'm correct.

[VT-565]

standard upper control arms are pressed steel and they look like crap, but they're deceptively strong. you could box them along with the lower control arms, i've also seen adjustable one so you can dial in your pinion angle.

[Pub247]

I'd be more worried about where they mount on the chassis breaking than the arms themselves. Be Kneez if your bushes are pretty flogged then itd be worth grabbing these from the wreckers

[Bz Kn33z]

Mine look like they have been replaced they are red and look in good nick. but these ones at the wreckers where different and i havnt seen them on any other cars so its just weird.

[Pimpn1]

yeah same here i think mine have been replaced when the old owner replaced it with lower suspension, mine are red and in good nik too

[Bz Kn33z]

Are the arms different?

[Pimpn1]

i just took a photo for ya, not sure if it the part ur alking about tho haha

[Bz Kn33z]

Nah thats not it lol, its the trailing arms off the diff.

Thats the stabliser bar

[jatsvl]

pimpn1, you have a pet redback spider passenger under your car!

[VrWagz1]

^^LOL, i seen it too but i dont think its a red back. You gotta a awsome diff leak too.

[beefcream]

the boxed ones are a nolathane replacment part, i have the in mine
they look tons stronger lol but dunno on actual improments, i got them for the pressed bushers and because i was running a spool setup

[Calaber]

You talking about trailing arms i'm guessing? their main purpose is to stop forward and back movement of the diff if I'm correct.

The upper control arms serve two functions on the live rear axle Commodores. The first is to prevent the rear axle assembly from attempting to twist forward under accelleration. The second is to prevent lateral (sideways) movement of the axle when under way. That's why the two upper arms are angled outwards and not parallel with the car. It's not a very effective way of locating the axle and when the bushes clap out, the axle can move heaps sideways. That's where the Panhard rod does its job.

Holdens from HQ had rear coils and no panhard rod. Their rear axles could get really loose with age.

[Bz Kn33z]

the boxed ones are a nolathane replacment part, i have the in mine
they look tons stronger lol but dunno on actual improments, i got them for the pressed bushers and because i was running a spool setup

Could you take some pictures if you have some time on your hands

The upper control arms serve two functions on the live rear axle Commodores. The first is to prevent the rear axle assembly from attempting to twist forward under accelleration. The second is to prevent lateral (sideways) movement of the axle when under way. That's why the two upper arms are angled outwards and not parallel with the car. It's not a very effective way of locating the axle and when the bushes clap out, the axle can move heaps sideways. That's where the Panhard rod does its job.

Holdens from HQ had rear coils and no panhard rod. Their rear axles could get really loose with age.

So if the tailshaft was hitting the floor near diff under back seat could this be the course? cause alot of people replace the tailshaft centre bearings i did on my old VN and it still did it.
I just might grab them, i was looking for an adjustable panhard bar but there were none

[VR38]

The upper control arms serve two functions on the live rear axle Commodores. The first is to prevent the rear axle assembly from attempting to twist forward under accelleration.

That would be backwards, top arms are under tension when accelerating, and yes they stop the diff rotating forward when braking.

The second is to prevent lateral (sideways) movement of the axle when under way. That's why the two upper arms are angled outwards and not parallel with the car. It's not a very effective way of locating the axle and when the bushes clap out, the axle can move heaps sideways. That's where the Panhard rod does its job.

Holdens from HQ had rear coils and no panhard rod. Their rear axles could get really loose with age.

Commodore rear end looks pretty parallel to me (thats why they need the panhard bar, for lateral location), think you are thinking of Torana and HQ.

[VT-565]

The upper control arms serve two functions on the live rear axle Commodores. The first is to prevent the rear axle assembly from attempting to twist forward under accelleration.

Don't you mean the pinion will try and rotate upwards on acceleration?
Close, but no cigar.

The second is to prevent lateral (sideways) movement of the axle when under way. That's why the two upper arms are angled outwards and not parallel with the car. It's not a very effective way of locating the axle and when the bushes clap out, the axle can move heaps sideways. That's where the Panhard rod does its job.

Holdens from HQ had rear coils and no panhard rod. Their rear axles could get really loose with age.

WTF?

Did two different people type that?
A panhard rod is an acceptable method of diff housing location, IMO not as good as a watts link or a sliding wishbone, but it does its job.

[Calaber]

Don't you mean the pinion will try and rotate upwards on acceleration?
Close, but no cigar.




WTF?

Did two different people type that?
A panhard rod is an acceptable method of diff housing location, IMO not as good as a watts link or a sliding wishbone, but it does its job.

Yep, I'll admit my thinking was out with the upper arms, but what's your point regarding the panhard rod? I was saying that Commodores have them, HQ's onwards didn't (meaning HQ to WB, not Commodores.) The HQ had the angled upper arms to act as lateral locaters for the rear axle, but it wasn't very effective. The comment I made regarding the angle of those arms doesn't apply to Commies, I realised that after posting, as they are parallel, but the Commie has the panhard rod to do the lateral locating job.

You're right about the Panhard rod not being the best means of locating a live rear axle, but that's all you got with the Commodore.

[POVRTY]

i have the nolathane upper control arms in my commy and ive had no problems with them,
just wondering when drag cars set up there adjustable upper control arms, do the lengthen them or shorten them?