Leyland P76 Owners 2007

Technical

Discussion on rear shocks

This information is the views of private contributers and is only here as a guide !!!!

Certain stores continue to list HQ Holden shocks for the P76

Reply "John Ernst"

Despite assurances from people on this site who have been dealing with a certain store, This store still list (and sell) Rear HQ Holden Shocks for the P76.
As I said in earlier posts these shocks do not compress enough and will damage your car. The only rear Holden Shock they no longer list for the P76 is their Air Shocks.
The culprate part numbers are:
3303 3303 Touring Black Gas Shock
8003 8003 Comfort Gas Shock
9034 GSR9034 Gas Sports Ryder
All of the above are Holden HQ Rear Shocks NOT P76 and simply should
not be fitted to a P76!

Photos of shockers and Certain Store Part number for correct shocks

Reply "John Ernst"

Please find photos of the 8003 8003 Comfort Gas compared to a standard P76 you will see it doesn't compress enough by several centimeters it also expands beyond the normal P76 range meaning that it will not act as a King Pin when required.
The correct shock which also has enough capacity to cope with the angle of the Leyland is Pedders GSR 9192 D-0900023 these are fair dinkum shocks while it still does not compress completely to the right depth is will allow you to shim the bump stop far enough to take up the compression of the suspension.
Put these on the car and you will loose all the axle tramp associated with corrugations and cornering.

Reply "myp768"

Thanks for the advice John.
I am just about to replace the rear shocks on my V8 Super.
Can anyone give me advice on what might be suitable if I don't go to Pedders.
Are there any other makes of car which have similar rear shock absorbers.
I have heard people mention VY Commodores and even F Series Fords. Is there a definite answer?

Reply "John Ernst"

I heard the Hal Moloney used a pair of "Rancho" brand shocks on his rally car don't have any details of part numbers but I know he initially had problems with lack of compression punching holes and ripping bottom brackets..

Reply "Fleur and David Waters"

Adjustable rancho to suit a 4 runner.
The only real problem is that they have a knob on the outside when they rotate it fowls the body.
The problem is not the travel.
The original shocks are single action hydrolics.
Uprating shocks of the correct length without strengthen mounts is silly.
Uprating shocks not matched to the springs is silly.
The original shocks don't dampen on extention so dual action shocks damage the floor cracking the box section arond the weld nuts.
The stress on the small 4 bolts are excesive.
Bump stops are not part of the suspension.
They are travel limiters.
Other than the strange driveways, the axle should rarely come close.
Large rubber cones assist as used in utes and 1 tonners.
For the suspension to work properly the shock should be relocated mounted near vertical behind the axle.
This does not asist with sidways movement or tramping.

Reply "John Ernst"

While I know you Dave have rallied these things can't agree that the travel of the shockers won't have a impact on the lower mounts, as the stress fracture is always consistent with a downward tearing, again at the top of the mount my experience has been of the shockers punching through the top not tearing down.
All this is consistent with the weight of the rear of the car concentrating on these points probably over those driveways you talk about.
My point in relation to the bump stop is that they do in fact allow extreme forces of a completely compressed suspension to be taken up at the bump stop as apposed to the shock mounts as happens with the HQ Holden shocks.
In relation to matching spring rates to shockers it not an exact science, and as you know seat of pants is the best tester, just look at recent Wheels stories about the suspension "tuning" that occurred around the Toyota Aurion and Mitsubishi 380 where after all the computer matching the engineers still needed to change shockers on the run to find the best combo, not having the luxury of several million dollars worth of development we can only go by other people's experience and having a limited range to choose from you can either opt for what other people have found works (which is the reason for my post as silly as that may be) or have custom adjustables made by Koni at $650 per corner and experiment for yourself.
I'm just trying to give others the benefit of my research and experience; they can take it or leave it, I haven't had to reinforce mounts as I haven't changed the shock rating just the capacity.
The problem with angle of the mount is what I had mentioned earlier and is one reason the Armstrong Shockers have a bigger piston and greater oil capacity compared to the standard HQ Holden's of the time.
This is not to say the Leyland design was in any way flawed, Leyland where in fact very very clever in the design because by angling the shocks as they have it also picked up and controlled some of the twist forces that cause tramp, and some of the lateral forces that cause left right movement something you quite correctly point out a more
ideal up down shock would not be able to do.
When the XF Falcon came out it tried to control the lateral forces with the panhard bar but still had problems with tramp, this was able to be fixed by owners by fitting steering dampers to the lower control arms (steering dampers are designed to work on the horizontal plain).
The trade-off was the capacity of shock would be compromised on a P for this very reason the Pedder Shock we have found is ideal if people are to maintain the standard mount points as the additional reserve of the shock will more
than adequately compensate for a less than an ideal angle for efficient shock work which as working a shocker as a P76 does induces a lot more heat.
In relation to the original Armstrong shocks they most certainly were a dual action shock with both rebound and compression strokes controlled by blow off and leak valving I will post a cross-section diagram of a Armstong Shock of the time so people can see how they work and if you want I'll drop into to Pedders to have them rated for you, many of the "air shocks" of the time however weren't.
If you want to read more about the forces and science of Car Suspension and Handling, get Donald Barstow's book of this title.
Anyway now we need to know from you how you fixed the problem of the adjustment knob fowling the body, this forum is about solutions.
Last updated
Dec, 2005
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