Greetings and some suspension questions :)

[woot]

Hi guys, Long time reader(lurker) of this forum. About two years back I bought a NX Pajero GLX and having gone out for a few four wheel driving trips, I have recognised some limitations of the vehicle, and am ready to start on my upgrade journey

One of the thing I have noticed is the lack of under body clearance of the Pajero - It is very easy to bottom out on tracks, even when I tackle obstacles very slowly. I would like to

I have been reading up on all the suspension threads, and have decided to settle on Oztec following Old Jack's recommendation.
However, I am not quite sure what combination of components I should purchase.

The everyday fit out for the Pajero is(will soon be) as follows:

• 2 front passengers
• Bullbar
• Winch
• Bash plates
• Pioneer Platform
• Basic Awning

However, when on over-landing trips, I see the following being additionally loaded on the car:

• Roof Rear - Extra Spare Tire
• Roof Mid - 2x 20L Jerry
• Cargo Rear- 70L Esky
• Cargo Rear- Canvas Tent, Chairs, tables, Kitchen (and other standard camping equipment)
• Cargo Mid - 40L Water

I would really appreciate the help in choosing the right suspension components, and any recommendation in installers/mechanics in the Brisbane-Slacks Creek area would be a bonus!

[Two Emms]

Welcome to the forum woot

The suspension selection will be an adventure but knowing what you plant to load is a good start.

At first glance, that sounds like lot of weight on the roof

I have King springs and although its only been a week or two, I am very happy so far.

[old Jack]

Gen 4 suspension is very hard to get the coil selection correct so accurate axle weights are better to work with than guesstimates.

OJ.

[willneill]

Better to leave suspension until you fit everything (or close to), then weigh your vehicle. You may find all that gear weighs more than you think or even more than manufacturers spec.

As for for the weight on the roof, 100kg is max on road including the weight of the rack. Off road the allowance goes down to around 67kg I think. Allow 25kg for an alloy rack. So for long off-road touring you're left with 42kg for gear, give or take. I do trips with heavy loads up top, as I combine camping with surfing and carry a bunch of boards. I've done trips with up to 80kg including the weight of my ARB alloy rack, I do go off road with this weight but keep it to gravel roads, I drive slow and have never had any issues. Proper overlanding though, I would be stripping this back.

[Jasonmc73]

My problem with thinking suspension which once i fit bullbar bash plates i'll be doing is as follows,

When you travel about town one is empty,
When you travel to camp site one has trailer hitched, then off with campsite/ trailer

Drive about chosen location, example Fraser Island or wherever you may be once unhitched & campsite set or whatever.

The change in axle weight rear is all over the place, front end is more static, but i'm thinking spring towards no trailer on & airbag helper for heavy loads.

Hurts my head that one

[old Jack]

Hi Jason,

Just to make your head hurt even more, you need to consider the weight transfer off the front axle when you have a trailer, camper trailer or caravan hitched up and you are not using a correctly setup WDH. 150kg of towball load transfers approximately 70kg OFF the front axle and onto the rear axle so the net rear axle load has increased by 220kg!

Quite a few people that tow with significant towball loads and no WDH have been caught out by having the front suspension riding too high and the rear suspension riding too low when loaded and hitched up.

I continue to point out that the coil selection on the IFS and IRS of the Gen 3/4 is tricky and easy to get wrong! Getting it as good as it you can is still a compromise and sometimes airbags are required to supplement the upgraded rear coils when you have large differences between unloaded and loaded rear axle weights.

OJ.

[woot]

Thank you guys for the welcome and information!

I think you guys are right, I am overloading the roof. I'll weight the items individually to make sure I only load up to around 67kg.

I will get all the weighty mods done first, and then head to a weigh bridge

... Come to think of it.... The only place I can think of with a weigh bridge is the tip.....

[nj swb]

Hi woot,

I'll join others in welcoming you to the forum, and congratulate you on asking intelligent questions early.

Very rough numbers, trying to be "realistic" i.e. not over-estimate weights, I got to 600 kg of payload on your Pajero. On paper, about 100 kg inside GVM (good), but only 100 kg margin for error (bad). You'd be amazed how quickly you can add 100kg to your 4wd as you pack for a big trip.

As others have said, 2 jerries + spare tyre (no wheel) + the roof rack is a significant amount of weight. It may be within (just) the factory rating, but if you're travelling rough roads / tracks, dynamic loading could be significantly higher than Mitsubishi considered. Think about getting that lower.

40 litres of water cargo mid

OJ has a rack to carry a number of 10 litre jerries inside the cabin of his Challenger, as & when he needs them. I have an aux tank under the rear, which has good & bad aspects.

Good: I can carry 80 litres of additional fuel, down low and outside the cabin. Using it is as simple as hitting a switch on the dash, to transfer fuel to the factory tank. When I need fuel I can buy around 150 litres, which makes it worthwhile to shop around (I use "gas buddy") and save maybe 10 cents per litre (sometimes more...)

Bad: I'm always carrying the weight of the tank, whether I want it or not. When full, that extra weight is hanging behind the rear axle - so the 70 or so kg of diesel adds more than 70kg to the rear axle, and takes a few kg off the front axle. OJ's jerries are between his axles, a much better spot for extra weight. Because I use my Pajero in serious offroad conditions my tank has copped a hammering, and it's on my mind that the tank could get holed - so I could lose the lot before I get a chance to use it - OJ's jerries are much better protected. If I don't use the tank regularly it can gather condensation and rust, so that creates an incentive to use it - so filling up costs more, but I don't need to do it as often, and (as mentioned above) the extra cost is a great incentive to shop around for a better price.

[Jasonmc73]

Hi Jason,

Just to make your head hurt even more,

Quite a few people that tow with significant towball loads and no WDH have been caught out by having the front suspension riding too high and the rear suspension riding too low when loaded and hitched up.
Getting it as good as it you can is still a compromise and sometimes airbags are required to supplement the upgraded rear coils when you have large differences between unloaded and loaded rear axle weights.

OJ.

I'm leaning towards the Airbag route in my mind i have little option is reality.
More money
Not as reliable

[Jasonmc73]

Thank you guys for the welcome and information!


... Come to think of it.... The only place I can think of with a weigh bridge is the tip.....

Mate welcome, if you have trouble with the tip there are private weighbridges about.

Charge like wounded bull from memory i used one at Stapylton couple month back & from memory it was $30

If you have troubles finding one or with tip sing out

When i end up weighing my Pajero i'm gunna try tip me self

[Toshmegosh]

Hi Jason,

Just to make your head hurt even more, you need to consider the weight transfer off the front axle when you have a trailer, camper trailer or caravan hitched up and you are not using a correctly setup WDH. 150kg of towball load transfers approximately 70kg OFF the front axle and onto the rear axle so the net rear axle load has increased by 220kg!

Quite a few people that tow with significant towball loads and no WDH have been caught out by having the front suspension riding too high and the rear suspension riding too low when loaded and hitched up.

I continue to point out that the coil selection on the IFS and IRS of the Gen 3/4 is tricky and easy to get wrong! Getting it as good as it you can is still a compromise and sometimes airbags are required to supplement the upgraded rear coils when you have large differences between unloaded and loaded rear axle weights.

OJ.

Hi OJ

As a newbie to towing heavy loads I am very interested in the axle load/EBH change issue. Is the reduced weight on the front axle an issue of proportion, ie front vs rear axle % of total load, or is it the reduced absolute kgs loaded onto the front axle that impacts steering - I am assuming the former?

As per Jason I will address the increased rear load/reduced EBH with the airbags now installed

[old Jack]

Hi OJ

As a newbie to towing heavy loads I am very interested in the axle load/EBH change issue. Is the reduced weight on the front axle an issue of proportion, ie front vs rear axle % of total load, or is it the reduced absolute kgs loaded onto the front axle that impacts steering - I am assuming the former?

As per Jason I will address the increased rear load/reduced EBH with the airbags now installed

When you apply loads to any part of the vehicle that are rearwards of the rear axle there is a weight transfer from the front axle to the rear axle. Think of a seesaw except the pivot point, being the rear axle, is not located centrally. If you look at the Gen 3/4 LWB Pajero wheel base it is 2780mm long and the rear overhang is 1355mm + 200mm to the towball so that makes the rear overhang 1555mm so this combined with the wheelbase is 4330mm. This means that for every 100kg of towball download applied 155kg of weight is added to the rear axle, 55kg being transferred off the front axle. 100kg of weight added evenly to the cargo area means 125kg is added to the rear axle load, 25kg being transferred off the front axle.

So you can see how easy it is to overload the rear axle and take to much weight off the front axle. When you take weight off the front axle the front ride height increases, so the steering will lighten, front braking efficiency will decrease and front suspension droop travel will decrease, this can result is early or unwanted activation of the ABS, TC and ESC systems under certain conditions. Therefore care needs to be taken when increasing the front ride height, if you go too high when unloaded you can have problems when you load and hitch up.

Fitting heavier duty rear coils or rear airbags will only change the rear ride height and not the transfer of weight off the front axle and onto the rear. Only a correctly setup WDH can compensate for the effect of towball loads on the front axle. Careful loading of the vehicle and moving all the heavy items forward towards the rear axle will also assist.

OJ.

[Jasonmc73]

You'll soon feel it if your vehicle has too much weight transfer, in my experience it is quite evident & it is not a very nice feeling at all.

Fortunate for me with my camper trailer, which is only a soft floor Lifestyle built camper Tare 950kg's via compliance not weighed with impressive GVM 1900KG's Aussie built one, at this stage Pajero standard suspension with bum dragging on the ground EBH 480mm rough measure, there is no ill effect to steering. No ground clearance either!!

Feels better than my Triton ute to drive like that with camper attached , although the camper was not fully loaded

The back Pajero cargo area of vehicle clothes & blankets, exactly what i did with ute, also intend on removing 3rd row seat when towing camper for more than a local trip or i wouldn't bother.
Toss toolbag & recovery bag in back at destination when unhitched.

Be very interested to measure the ball weight which i will in time, maybe i don't want to know ingnorance is bliss

[old Jack]

List of Public Weighbridges in Qld.

https://publicweighbridgeaustralia.com.au/weighbridge-locations/queensland/

If you are not going to weigh your vehicle unloaded and loaded then you are taking a gamble on getting the best coil for your application, you are spending $2,000+ on a suspension upgrade on a $30,000 to $60,000 vehicle and all you will save is a bit of time and $50!

No issues with using airbags as a supplement to upgraded rear coils if required but if you are heavily loaded, travelling long distances and off the bitumen then I would not rely on airbags alone.

OJ.

[Toshmegosh]

I have been particularly anal around Pajero and van weights before buying either, and have a very detailed spreadsheet which hopefully will be close to reality (van is being manufactured in Melbourne )

Summary of hopefully worse case attached, and as expected the limit I am coming closest to is rear axle load. Hopefully around 50 kg net load off the front axle will not trigger steering issues?