Suspension 1998 GLS wide body

[motorazr]

My paj is currently running the stock coils in the rear from the day it was born, recently i took out the cargo seats and installed 2 drawers and a 65 litre fridge, along with an 80ah agm battery.
The drawers are full.
I have noticed when going over some bumps that the rear bounces around a little so have decided to put some new springs in it.
I was able to source some OME910 springs, and intend to team this with some foam shocks eventually.
The springs have a 15mm lift and are rated medium to GVM by old man emu specs, i also occassionally tow a van which has a ball weight of around 135kg.
Do i need higher rated springs or will i be able to get away with the 910’s.

[old Jack]

The rear suspension on the Gen 2 Pajero carried over to the PA Challenger then The PB/PC Challenger and now the Pajero Sport so there are lots of coil options to choose from, which could give you a better outcome for a lower cost.


I have a lot of spring data and calculations for the PB/PC Challenger and some for the Pajero Sport so I can convert these over to suit the Gen 2 but I need 3 measurements and 1 additional piece of information.


1. When the car is parked on level ground what is the measurement between the centre of the rear wheel hub and the underside if the wheel arch in a vertical line?


2. What is the gross rear axle weight, you just need to fins a weigh bridge and drive on to it so the front wheels are just off the weighing platform and the rear wheels are as close the the centre of the weighing platform as possible.


3. Jack a rear wheel up off the ground using a jack under the axle, remove the wheel and measure the distance between the top of the axle articulation bump stop and the underside of the chassis where the bump stop contacts.


4.Whilst the rear wheel is removed, please check if there is a rubber cone spring inside the coil, if there is it will be attached to the top spring pad.


OJ.

[tomwithannl]

My paj is currently running the stock coils in the rear from the day it was born, recently i took out the cargo seats and installed 2 drawers and a 65 litre fridge, along with an 80ah agm battery.
The drawers are full.
I have noticed when going over some bumps that the rear bounces around a little so have decided to put some new springs in it.
I was able to source some OME910 springs, and intend to team this with some foam shocks eventually.
The springs have a 15mm lift and are rated medium to GVM by old man emu specs, i also occassionally tow a van which has a ball weight of around 135kg.
Do i need higher rated springs or will i be able to get away with the 910’s.

Hi. You don't actually say if your ride height is a problem only that it "bounces around a little".
If you are happy with your ride height I would just be renewing/upgrading the shocks as they are likely to be original.
Just my opinion
PS The rear most seats are Bloo*y heavy, would not surpise me if you are actually lighter now!

Tom

[nj swb]

I have noticed when going over some bumps that the rear bounces around a little so have decided to put some new springs in it.

A classic concept in physics is the mass-spring-damper system. A mass on a spring (if disturbed) will oscillate endlessly - unless it is damped. Your rear bouncing around a little is a classic symptom of an underdamped system, so it is most likely that your dampers (shock absorbers) are the problem, not the springs.

I was able to source some OME910 springs,

I have some of those for Shorty.

Do i need higher rated springs or will i be able to get away with the 910’s.

You're going about this the right way. A mass-spring-damper system needs to be "tuned", to ensure that all three components work together.

You've increased the mass, and noticed the performance has suffered. Next step is to decide on the right springs to suit the mass, then look at dampers.

From what you've posted, the 910s may be adequate, but you may need something heavier. Work with OJ on that, but don't expect new springs (if you change them) to magically cure your damper issues.

Once you are comfortable with your chosen springs, then you can start talking to suppliers about damper options.

Keep us updated with your progress.

[motorazr]

Thanks guys will keep you updated.

[Quinno]

If it's any use to you I have 2 spring options for you that I have taken off my Gen II Pajero. Option 1 is a 420mm long variable rate spring 165-200lb/in by Tough Dog. Option 2 is a 400mm free length by lovells that is heavy duty 175-235lb/in. Also got Tough Dog big bore shocks. Done about 30,000km. My Pajero crapped the gearbox so I am stripping it for parts now.

[motorazr]

Have had the ome 910’s installed along with the pedders foam shocks. The mechanic reported that the new springs although the same height as the old springs, were substantially thicker and a bugger to compress and get in.
Foam shocks were put in the front and new superpro bushes put in the front end also.
Will test it over the next week or so and perhaps get a load test done by pedders.
Will report back in a few weeks.

[motorazr]

The back end no longer floats and bounces over speed humps, it seems to have solidified the vehicle into something that no longer leans around corners at speed. Most impressed by the new suspension and worth the money spent.

[nj swb]

The back end no longer floats and bounces over speed humps, it seems to have solidified the vehicle into something that no longer leans around corners at speed.

Somewhere along the line, I removed Shorty's rear sway bar, and didn't notice a difference in on-road handling - but I definitely noticed an improvement in stability in chassis-twisting rough stuff.

When I had Shorty engineered in SA, Shorty passed the race-track swerved tests with flying colours - with the wanna-be free-loader sway bar on the ground beside me.

Most after-market heavy duty springs will provide more roll-stiffness (without rear sway bar) than the factory setup with sway bar. I expect that you could now remove your rear sway bar, and still lean less around corners.

[BruceandBobbi]

Somewhere along the line, I removed Shorty's rear sway bar, and didn't notice a difference in on-road handling - but I definitely noticed an improvement in stability in chassis-twisting rough stuff.

When I had Shorty engineered in SA, Shorty passed the race-track swerved tests with flying colours - with the wanna-be free-loader sway bar on the ground beside me.

Most after-market heavy duty springs will provide more roll-stiffness (without rear sway bar) than the factory setup with sway bar. I expect that you could now remove your rear sway bar, and still lean less around corners.

Would that apply to Gen 4 shorties as well?

[stumagoo]

Would that apply to Gen 4 shorties as well?

I very much doubt it, I suspect the independent suspension is much more likely to sway and I also would imagine your suspension is designed with more comfort in mind than the gen 2 - so softer

[motorazr]

Was told that my torsion bars are getting old as now after the new gear has been installed they are wound up about as far as they will go. I have been able to source a pair of heavy duty bars for a couple of hundred for the pair so will probably grab them and hang on to them.

[stumagoo]

Was told that my torsion bars are getting old as now after the new gear has been installed they are wound up about as far as they will go. I have been able to source a pair of heavy duty bars for a couple of hundred for the pair so will probably grab them and hang on to them.

what have you installed.... remember a winch and steel bull bar can add nearly 100kg's to the front end and old or not the stock torsion bars are not really designed to carry that extra weight.

[motorazr]

Have added a light alloy bar and a couple of spotlights, so not a great deal of extra weight in the front. Most of it is in the rear and mid section.

[aussieguy]

what have you installed.... remember a winch and steel bull bar can add nearly 100kg's to the front end and old or not the stock torsion bars are not really designed to carry that extra weight.

So what is the diameter of stock vs "heavy duty" options?



I ask because I have been told by a suspension guy that is happy to sell me an upgrade that after market torsion bars are same diameteras the stock bars, and that stock are plenty good enough to do a steel bar + winch when wound up.