Airbags on Std Suspension

[Quinnie]

Hi,

I am looking for some advice on Suspension upgrade on behalf of my father who has a purchased a 2016 Pajero Sport (5 Seater) and plans to tow a caravan with a ball weight around 220kg and a van weight around 2.5t.

I have a Pajero and tow my own van. I have installed Bilstiens and Lovells with HD springs and 40mm lift which for my use works a treat but I’m unsure if Dad will like the feel of constant HD Springs.

I am wondering if airbags could be installed on the standard suspension, and if that doesn’t cut the mustard, can they be transferred to a new suspension set up with upgraded shocks and springs.

I would really appreciate the advice of anyone who has upgraded their suspension for towing but still maintained a good balance between unladen comfort and performance when towing.

Thanks in advance,

Steve

[Jizza]

Hi,

I am looking for some advice on Suspension upgrade on behalf of my father who has a purchased a 2016 Pajero Sport (5 Seater) and plans to tow a caravan with a ball weight around 220kg and a van weight around 2.5t.

I have a Pajero and tow my own van. I have installed Bilstiens and Lovells with HD springs and 40mm lift which for my use works a treat but I’m unsure if Dad will like the feel of constant HD Springs.

I am wondering if airbags could be installed on the standard suspension, and if that doesn’t cut the mustard, can they be transferred to a new suspension set up with upgraded shocks and springs.

I would really appreciate the advice of anyone who has upgraded their suspension for towing but still maintained a good balance between unladen comfort and performance when towing.

Thanks in advance,

Steve

A little out of the scope of your query but also relevant, I installed bags in the rear of my previous car, a 2009 Outlander VRX. I did change the rear springs over to Pedders springs but only because the stockers on those cars would sag by 30mm lower than the front even without towing.

I used to tow a 1.5tonne camper trailer with two full size dirtbikes on the drawbar. Unsure what the ball weight was but it handled it fine, much better with the bags of course.

Hope it helps a little, there is no reason you would have any issues installing them, and then re-using them should he decide to upgrade the shocks and springs later on

[old Jack]

Hi Steve,

The Pajero Sport has much a different rear suspension than a IRS Pajero so what works on IRS Pajero doesn't work on the live axle coil suspension of the Pajero Sport/Challenger.

The Pajero Sport has identical rear suspension to the PB/PC Challenger and I have spent a lot of time working out what works and what doesn't for multiple applications. What suits an on road car with light loads is different to a car towing heavy on road and different again to one that ventures off road at GVM +. Many owners have used my suggestions and all have been happy with the upgrades they have done.

The PS like the Challenger has very soft progressive rate rear coils that do not carry weight that well and there are internal rubber cone helper springs for when the suspension gets some weight applied, but these are too short so their assistance is too late in the suspension travel and they only offer 75kgs of assistance before they compress solid..

So this is for a Pajero Sport that is not going hard off road, towball down load 220kg, using a correctly setup WDH and little weight in the rear seat or cargo area. This is not a full suspension upgrade but a rear only to improve the ride and load caring ability. 220kg on the ball is like 340kg in the back seat or in the forward section of the cargo area directly over the axle.


If you fit airbags then you lose the rubber cone helper spring assistance and this puts extra load and dependency on the airbags, this means if you have a leak and the airbag loses pressure you are worse off than standard suspension without airbags. Airbags will cost you between $300 and $500 + about $150 to $200 in labour fit. Personally I do not like to recommend airbags as a substitute for correctly rated springs and I think they are not good value for money.

l would recommend upgrading the rear coils to King KCRS-23 this is a progressive rate coil that has a ride height about 10mm to 15mm higher than a new factory coils (it does not take much load and time for the standard coils to sag) but has a 25% heavier loaded spring rate and a 10% heavier unloaded spring rate. I would also upgrade the rubber cone helper springs to Peddars PN 5899, these start assisting earlier in the spring travel, are softer initially and more progressive with a greater load assistance (at least double of the factory cone springs) before they become a solid bumpstop.
Coils will cost about $200 a pair, Peddars Cone Springs $125 a pair and $150 to $200 in labour to fit.
The end result will be a slightly firmer but much better controlled rear suspension that will pitch less and will not bottom out hard. You will not need to worry about leaking airbags and you should be able to reduce the tension settings on the WDH which is a good thing.

OJ.

[Quinnie]

Hi Jizza,

Thanks for your advice, is always good to hear about other people's experiences.

Hi old jack,

I really appreciate your detailed and well explained information, from what you have described this sounds like an excellent solution for dad that will give him the load carrying capability without compromising ride quality

having been a long time forum reader having read plenty of your advice helping others, Im looking forward to showing dad this advice.

I'll let you know the end result.

Thanks again,

Steve

[old Jack]

No Problems Steve,

A thread or 2 if you want some more info;

https://www2.pajeroclub.com.au/forum/showthread.php?t=45233

https://www2.pajeroclub.com.au/forum/showthread.php?t=51272

OJ.

[jvelden]

Hi Steve,

The Pajero Sport has much a different rear suspension than a IRS Pajero so what works on IRS Pajero doesn't work on the live axle coil suspension of the Pajero Sport/Challenger.

The Pajero Sport has identical rear suspension to the PB/PC Challenger and I have spent a lot of time working out what works and what doesn't for multiple applications. What suits an on road car with light loads is different to a car towing heavy on road and different again to one that ventures off road at GVM +. Many owners have used my suggestions and all have been happy with the upgrades they have done.

The PS like the Challenger has very soft progressive rate rear coils that do not carry weight that well and there are internal rubber cone helper springs for when the suspension gets some weight applied, but these are too short so their assistance is too late in the suspension travel and they only offer 75kgs of assistance before they compress solid..

So this is for a Pajero Sport that is not going hard off road, towball down load 220kg, using a correctly setup WDH and little weight in the rear seat or cargo area. This is not a full suspension upgrade but a rear only to improve the ride and load caring ability. 220kg on the ball is like 340kg in the back seat or in the forward section of the cargo area directly over the axle.


If you fit airbags then you lose the rubber cone helper spring assistance and this puts extra load and dependency on the airbags, this means if you have a leak and the airbag loses pressure you are worse off than standard suspension without airbags. Airbags will cost you between $300 and $500 + about $150 to $200 in labour fit. Personally I do not like to recommend airbags as a substitute for correctly rated springs and I think they are not good value for money.

l would recommend upgrading the rear coils to King KCRS-23 this is a progressive rate coil that has a ride height about 10mm to 15mm higher than a new factory coils (it does not take much load and time for the standard coils to sag) but has a 25% heavier loaded spring rate and a 10% heavier unloaded spring rate. I would also upgrade the rubber cone helper springs to Peddars PN 5899, these start assisting earlier in the spring travel, are softer initially and more progressive with a greater load assistance (at least double of the factory cone springs) before they become a solid bumpstop.
Coils will cost about $200 a pair, Peddars Cone Springs $125 a pair and $150 to $200 in labour to fit.
The end result will be a slightly firmer but much better controlled rear suspension that will pitch less and will not bottom out hard. You will not need to worry about leaking airbags and you should be able to reduce the tension settings on the WDH which is a good thing.

OJ.

Hi Jack. Thanks for your interesting post. I have a 2017 PS with a 35 kg bullbar, 112litre long range fuel tank (Brown Davis, weighing 45k plus fuel) and am towing a 1200 k caravan (when fully loaded) with a towball down weight of 125k. I have removed the 3rd row seats, which saves about 35k. When we are fully loaded for travel the Pajero weighs about 2600, including the towball downweight. I doubt that I will ever be doing any serious off-roading. I do not have a WDH. Would you give the same suspension upgrade advice to me?

[DID Dash]

Hey jvelden, I put the Kings/Pedders on my Challenger about 12 months ago and could not be happier. Great ride comfort around town unladen, and carry a load plus 120 kg ball load / 1400 camper when we are touring. I don't recollect anyone complaining of this combo on Challenger or Pajero Sport unless they are running very heavy loads where something heavier is required.

[Harry230]

King Springs Pedders Bumpers

Hi OJ and Did Dash,

Any need to upgrade the shocks when upgrading springs and rubber cones. I am looking to upgrade for towing a van with approx. 150 - 180 kg ball down weight.

Realise this is an old thread but would like some advice.

thanks, and regards,
Harry.

[old Jack]

Hi OJ and Did Dash,

Any need to upgrade the shocks when upgrading springs and rubber cones. I am looking to upgrade for towing a van with approx. 150 - 180 kg ball down weight.

Realise this is an old thread but would like some advice.

thanks, and regards,
Harry.

If your shockers are under 60,000kms, in good condition and so are not doing hundreds of kilometres of corrugated dirt roads then then factory shockers should be ok. It really gets down to personal choice, how you use the vehicle and what your expectations are.
Just replacing the rear coils and rubber cones will significantly change the way your PS handles particularly when towing.

OJ.

[DID Dash]

I put the cones on my Challenger at 60000 kms with the original shocks still there. Traded the Challenger at 80000 kms for the Pajero Sport , shocks still ok but suppose getting tired. Cones went on the Pajero Sport from new with OE shocks. Done about 9000 kms. No regrets.

[Harry230]

Thanks both for reply.

I notice on the King Springs site the KCRS-23 is listed as raised and standard heights. I am assuming you both have fitted the raised height version. Seems to make sense for improving load and attitude under load. Looking back over similar postings for Challenger and PS seems the springs used raise back end 20-30mm so again assuming the raised version for Challenger listed on the KS site is the correct one to use. https://kingsprings.com.au/catalogue...ct/992/kcrs-23


thanks, Harry

[old Jack]

Hi Harry,

The KCRS-23 is a standard height coil, which increases the unladen ride height slightly but gives a much higher spring rate, see this post.

https://www2.pajeroclub.com.au/forum/showpost.php?p=539401&postcount=3

K= King
C = Coil
R = Rear
S= Standard height.

This is the upgrade coil to use if you have little or no fixed extra weight in the rear of the vehicle all the time. However if you have a drawer system, auxiliary battery, recovery gear and lots of tools that collectively weighs several hundred kgs or 150-200kg of rear passenger weight then the KCRS-23 are likely to be too light a coil for your application.

If you can either weigh your rear axle or list and weigh the individual items that are in the rear of the car all the time then I can look to see if the KCRS-23 is the best fit or if another coil would carry your loads better.

OJ.

[Harry230]

Thanks for the offer OJ and will probably take you up on your offer of matching a springset.

I will be picking up a new caravan in Adelaide (driving from Perth) in March and I will update the suspension to suit upon return (plan to take 3 - 4 weeks). I am not a fan of the WDH and suspect the rear of the PS will be a little light on for around a 180 kg ball download. I will be travelling reasonably lightly when returning and if any short term problems I plan to overcome temporarily by diligent balancing of the caravan. It comes with ESC so should be manageable.

Will most likely prompt you for assistance in a month or two. I was going to upgrade early but it makes sense to understand the basic load to be carried by the vehicle and also ball weight first. The PS is only 7 months old so hopefully all good.

The KS site is a bit confusing as they list both a standard height and raised height under the KCRS-23, or is it the same spring that is standard height for Pajero and slightly raised for Challenger/PS

Appreciate the help.

regards Harry..

[old Jack]

Thanks for the offer OJ and will probably take you up on your offer of matching a springset.

I will be picking up a new caravan in Adelaide (driving from Perth) in March and I will update the suspension to suit upon return (plan to take 3 - 4 weeks). I am not a fan of the WDH and suspect the rear of the PS will be a little light on for around a 180 kg ball download. I will be travelling reasonably lightly when returning and if any short term problems I plan to overcome temporarily by diligent balancing of the caravan. It comes with ESC so should be manageable.

Will most likely prompt you for assistance in a month or two. I was going to upgrade early but it makes sense to understand the basic load to be carried by the vehicle and also ball weight first. The PS is only 7 months old so hopefully all good.

The KS site is a bit confusing as they list both a standard height and raised height under the KCRS-23, or is it the same spring that is standard height for Pajero and slightly raised for Challenger/PS

Appreciate the help.

regards Harry..

Hi Harry,


I have done a KCRS-23 + 5899 rubber cone upgrade to "2slow" PS about a year or so ago so best to send him a PM and get his thoughts and ride heights as I seem to recall he does tow heavy with his PS but I cannot remember the ball weight.

I would strongly recommend you do the rear coils and cone upgrade before you pick up the new caravan particularly since you are not intending to use a WDH. The stock rear coils on the PS are the same as the Challenger and these do not carry weight well, your 180kg ball load will also result in another 40kg-60kg of weight transfer off the front axle if you are not using a WDH so that make the extra load on the rear coils at 220kg to 240kg.

I do not tow heavy or regularly but if I did then from my research the Anderson WDH is the WDH I would look closely at using.

Side winds and passing truck gust across the Nullarbor is a real concern and relying on the vehicle's ESC and Trailer Sway Control to counteract an issue after it has happened rather than preventing it from happening in the first place is fraught with danger and a case of "shutting the gate after the horse has bolted".


OJ.

[dragonjon]

I have done a KCRS-23 + 5899 rubber cone upgrade
Iwas towing a 2100kg new age bilby with old school shepherd hook WDH but not needed
Now towing 1600kg new age gecko poptop no WDH sits level
I highly recommend you take OLD JACKS advice as did I