Submitted: Sunday, Jun 12, 2005 at 22:11
ThreadID: 23813 Views:3655 Replies:11 FollowUps:13
This Thread has been Archived
Due to an extended remote trip requiring me to carry around 300lt fuel, 100 lt water,etc, etc, the rig was starting to sag a little at the back.I had Polyairs fitted during the week and the result seems pretty good.
I have Lovell springs and Bilstein shocks already fitted,and according the rep, the Bilsteins with thier velocity valving work really well with the Polyairs....so instead of going to heavier springs, the Polyair option and flexability means you can lower the pressure in the bags as the load in the rig progressively is reduced/used
Anyone had good or bad experiences with Polyairs?
Back Expand Un-Read 0 Moderator

Reply By: Steve - Sunday, Jun 12, 2005 at 22:13

Sunday, Jun 12, 2005 at 22:13
Had them on a n 80 series for 5 years and they are the best thing since sliced bread....best money i ever spent on my rig...and that's some !!!
AnswerID: 115493

Reply By: Member - Paul P (Bris) - Sunday, Jun 12, 2005 at 22:25

Sunday, Jun 12, 2005 at 22:25

They work well. Make sure you keep some air in them ( as per the instructions ) even when empty.

I have used a set on a previous vehicle for 9 years without problems. I have only seen one set failed and I suspected a failure to keep them inflated resulted in a puncture. ( a rock gets between the bag and the coil ).

Pump them up before you load. I use a good quality bicycle pump or 12 volt air pump. Let air out to obtain a level vehicle after loading.

They may give you a better ride in the rear.


AnswerID: 115495

Reply By: Member - Jeff M (WA) - Sunday, Jun 12, 2005 at 22:32

Sunday, Jun 12, 2005 at 22:32
I'm running the Firestone Air Spring Helpers (bascially the same as the poly airs) and find them to be fantastic, they really reduced a lot of body roll after I removed my sway bar too.

AnswerID: 115496

Reply By: Crackles - Sunday, Jun 12, 2005 at 22:45

Sunday, Jun 12, 2005 at 22:45
Only issue I've had was a split air line so I now carry a bit of spare hose & a joiner.
Have seen & heard of several bags bursting which I put down to relying too much on the bags to carry the weight or just being unlucky to get a rock caught in the spring. If you have upgraded the springs already it would lessen the chance of damage. My 105 cruiser has the medium Lovells springs together with the polyairs. I have a policy of only pumping them up to 25PSI not the maximum 30psi as recomended thus allowing the springs to carry their share.(Just my idea but has worked well on the most remote of tracks)
The Polyairs seem to work best fitted on coil sprung vehicles while leaf sprung are better matched with the 100 PSI rubber type. Tried them on a Hilux once & they restricted wheel travel too much.
Only down side is they do tend to make the back of the car bounce a little more when empty (even after reducing the preasure) but the Bilteins may control that better on yours. Earlier fitments had trouble with the airline rubbing where it passes through the top of the spring but that seems to be fixed now by drilling alot larger hole.
Where are you heading Joe that requires 300 litres?
Cheers Craig..........
AnswerID: 115499

Follow Up By: Joe - Sunday, Jun 12, 2005 at 23:13

Sunday, Jun 12, 2005 at 23:13
Hi Craig,
Mine have 20psi in them for same reason....but they seem just a little more bouncy with the rig fully loaded for this trip.... than the original setup when it was more moderately loaded for a week long trip.
I so was really hoping that with say 5psi, and usual weekend load they would allow the original suspension setup.... which was excellent... to not be effected.
I'm headed to the Simpson, up the Hay River.
FollowupID: 371163

Follow Up By: Member - Jeff M (WA) - Monday, Jun 13, 2005 at 11:45

Monday, Jun 13, 2005 at 11:45
Hmmm, interesting, obviously more difference in the Firestones that I first though. The maximum for the Firestones is 35psi,not 30 and I reguarly run mine at 35 when we go away. Around down I run mine at about 20psi.
My airlines also run out the bottom of the air bag, not the top... The airlines are polyutheraine type and would be very hard to break, even with some rubbing, but the kit also came with a braided type cover for them.

How do the bags effect articulation on a Hilux more than any other rigid axel vehicle?
FollowupID: 371184

Follow Up By: mfewster - Monday, Jun 13, 2005 at 14:00

Monday, Jun 13, 2005 at 14:00
Crackles, I was going to fit airbags on a 60 series, so i'm interested in your comment on 100pSI rubber type being better for leaf sprung vehicles. What are 100 psi rubber type? Brand name and supllier also please. Anyone else have comments re polys on a leafspring setup?
FollowupID: 371195

Follow Up By: Crackles - Monday, Jun 13, 2005 at 18:03

Monday, Jun 13, 2005 at 18:03
O...... you're that lcool Joe :-))

Jeff on my hilux I fitted the Polyairs inside the mini coils as supplied in the kit but the bag size needed to support the rear of the car was then too tall to be compressed in the small distance between the spring & chassis. From memory when the spring had bottomed out on the bump stop there was less than 100mm of room for the bag & was so distorted it wouldn't have lasted a week up the bush.

Mike the rubber air bags I mentioned are from Firestone I believe & alot heavier duty than the Polyairs. Their bellows construction are more suitable for leaf sprung vehicles (IMHO) as they compress more. I have a good friend with a grossly overloaded 78 series with a set that carrys a Trayon camper & they have performed faultlessly on the roughest of tracks. Albury 4x4 centre fitted them from memory but are widely available.
Cheers Craig..........
FollowupID: 371216

Follow Up By: Member - Jeff M (WA) - Tuesday, Jun 14, 2005 at 13:37

Tuesday, Jun 14, 2005 at 13:37
Crackles, In the instructions for my Firestone's it told me to haxsaw off the bump stop so there was more room for articulation and the bag. Perhaps Polyair didn't think of this?
FollowupID: 371310

Reply By: Member - Banjo (SA) - Monday, Jun 13, 2005 at 08:36

Monday, Jun 13, 2005 at 08:36
I use the polyairs too Joe but am mindful of the fact that they are not a cure-all for high load rates. There have been reports on this forum quite some time back re spring mountings being broken off a chassis. The bags are good to a point, but if you pump them up tight and load the vehicle to high levels, you have of course reduced the springing of the car significantly. I'm using a camper trailer which takes me out of a few trip plans, but I prefer that because any load can be spread across 6 wheels - all that fuel, water, people and gear sounds to be a stressful formula for any vehicle. I thought I'd heard travellers suggest that most vehicles get across the Simpson on about 150L of fuel at most. Re the Bilsteins - I'm looking to put them on the front of my TD Jack - only thing is that reports here suggest they might be a bit "hard" for the wishbone, torsion system, transferring lots of harsh ride to the cab. Have you seen any useful info I could tap into ?
AnswerID: 115506

Follow Up By: Joe - Monday, Jun 13, 2005 at 11:32

Monday, Jun 13, 2005 at 11:32
Hi Banjo,
Our Hay River trip is south north across the Simpson and we have over 700 Km between fuel and water. No track in the mddle seaction of the trip, just GPS points.

The Bilsteins with Lovells an my 120 are medium rated and in fact rode smoother than OEM setup...and this is confirmed by back to back comparisions by fellow drivers of standard 120 who I gave a drive on same section of "test track"

I'm not qualified to comment on your Jack, but you could speak to Darren McRae at AFT 4x4 in Geelong.
FollowupID: 371183

Follow Up By: Member - Banjo (SA) - Monday, Jun 13, 2005 at 17:35

Monday, Jun 13, 2005 at 17:35
Understood Joe - that is a different plan indeed...thanks re the 4 X 4 contact .... will give him a buzz.
FollowupID: 371209

Follow Up By: Joe - Monday, Jun 13, 2005 at 17:44

Monday, Jun 13, 2005 at 17:44
Gave you a bum steer....it's ATS 4x4....not AFT....ph 0352216599...good luck
FollowupID: 371210

Follow Up By: Member - Banjo (SA) - Monday, Jun 13, 2005 at 19:14

Monday, Jun 13, 2005 at 19:14
Noted - thanks a lot Joe.
FollowupID: 371226

Reply By: Outnabout David (SA) - Monday, Jun 13, 2005 at 09:22

Monday, Jun 13, 2005 at 09:22
Hi Joe,

I have had two sets in two Prado's and have had two bags go. First one developed a hole at the top and replaced under warranty and the second one rubbed through on the side. I probably didn't keep enough air in them unloaded. For the cost I reckon it is just as easy to have another set of springs for the trip and swap them over when needed. Even a novice can easily fit them to the rear if they know how to. Joe how are you going to carry that extra fuel. You are usually loaded right up to the hilt anyway.........lol

Have a safe trip Wish I was travelling with you guys.
AnswerID: 115519

Follow Up By: Joe - Monday, Jun 13, 2005 at 11:18

Monday, Jun 13, 2005 at 11:18
Hi David,
I'm sure you will be out with us again before long!

OK you have had some drama with them, overall the balance from the feed back is postive....nothing is ever perfect....they are on now, but I do have option of having them removed and going with heavier springs, before leaving if I'm not happy....but I'm inclined to stick with them. Keeping 5psi in them when not loaded seems very important.
I have the 120 roof rack set up with 4 marine fuel tanks(92lt) and fuel line fittings that snap on and deliver the fuel into the rig without hasstle.
Took out the rear seats and other stuff that totalled 100kg.
100lt of water is behind the front seats.Once we have done the Hay River with Darren and Guy's Marion and I are heading off on our own from Alice Sprigs, Tannimi, Balgo Hills, Halls Creek, Kananara, Kakadu and anywhere else we feel safe travelling alone...told everyone back in around 2 months.
Look forward to being together on a trip again.
FollowupID: 371182

Reply By: Member - Cocka - Monday, Jun 13, 2005 at 09:54

Monday, Jun 13, 2005 at 09:54
Joe ther're the best thing since sliced bread. Especially the Firestones but like you I have the PA's.
In standard road use unloaded and with low pressure in the PA's I make a point of measuring the level of my rig (from the wheel archs to the lower edge wheel rims) and at night time go out and adjust the spotties to make sure they shine where I want them to.

As per the instructions, inflat the PA's and load the vehicle up & then reduce the presure until the vehicles square again & so are your lights. Your right, it's easy to reduce pressure in the PA's as the load is lessened. If you happen to have to do any night driving which is usually most unlikely the spotties will soon tell you if your vehicles level or not, provided you havn't smacked a roo or two.

I've never heard of anyone having a problem if used as per instructions. Mine are well protected set in behind the axel housing but I'm conscious of short sharp stakes in the middle little used tracks that may rear up and cause damage to the PA or hoses.

Good luck up the Hay it's on my agenda in a couple of years.
AnswerID: 115523

Reply By: Joe - Monday, Jun 13, 2005 at 11:34

Monday, Jun 13, 2005 at 11:34
Hi everyone,
And Crackles from Lcool I suspect?...hi mate

Thank's for all that feed back extremely valuable
AnswerID: 115530

Reply By: Outnabout David (SA) - Monday, Jun 13, 2005 at 12:24

Monday, Jun 13, 2005 at 12:24
Hey Joe,

Hope Darren doesn't have a supersized bottle of stone's green ginger. That would make a big whooska with all your fuel.........lol

Sounds like you will have a trip to remember you lucky bugga's. I want to see plenty of photo's
AnswerID: 115535

Reply By: Bob of KAOS - Monday, Jun 13, 2005 at 18:31

Monday, Jun 13, 2005 at 18:31
I have the polyairs and they seem to work a treat but as someone said above nothing is magic, and everything is a compromise. Ultimately, the extra load is borne by the tyres and the chassis and something is going to give sooner rather than later. I'd work on the weight carried. 300 L sounds a lot for 700 km. What are you driving? At 20 L per 100 km you will need 140 L for your 700 km. Is it possible to burn fuel at twice that rate? How many people? 100 L of water may be fine for midsummer, but if you aren't having a shower every day you will need less.

200 L of fuel and 40 L of water and we've saved you 160 kg already (equivalent to two adult passengers)

In my experience, carrying more weight than necessary is a far greater risk than not carrying enough fuel or water. On a Simpson Desert crossing I carried the recommended 200L of fuel but only used 90.
AnswerID: 115565

Follow Up By: Member - Banjo (SA) - Monday, Jun 13, 2005 at 19:19

Monday, Jun 13, 2005 at 19:19
Spot on Bob - after the foregoing posts, Joe will probably be ready for you sage advice on the "excessive weight" factor ...........he might already know that, but it is a biggy in my books - causes more trouble than commonly known I think.
FollowupID: 371227

Follow Up By: Joe - Monday, Jun 13, 2005 at 19:34

Monday, Jun 13, 2005 at 19:34
Hi Bob,
Here's my calculations for fuel...V6 petrol, and I know I have a safety margin....and I'm happy with it...I have detailed my reasons due to distance and remoteness of this trip...this information may help people make thier own decisions.
Given fuel will be used as we go the weight issue rapidly reduces...On first part of the trip we can accurately check consumption when we do the Warbuton, Popoels; Corner Birsdville section and restock at Birdsville...I have an empty 20lt Jerry can which I'm taking empty but really do not expect to fill at Birdsville.We also have to allow that we may have turn back beyond the half way point if we can't get through further up the Hay River.

As to water I have 90 lt drinking water, for 8 days which is also generous but provides margin should any radiator problems surface.plus 5lt in the porta potty and 5lt in drink bottles....also not planning to shower.

Fuel test...done locally
Completed 779.km in the 120....add 5% further for the larger tyres ...actual
distance travelled 818km.
Fuel used 143.8lt....regular unleaded

That's 5.68km to each lt.
or 17.6lt per 100 km

55% driving was very short city trips into/out of Geelong(loaded to around 70% of camping goods)
45% driving was good gravel tracks and sealed country roads...to Glen Aire and back ( loaded for weekend camping including roof rack load)
All driven in high range tyre pressure @36psi

For The Hay River...
On board the main tanks hold 180..... 165 usable, plus 92 lt in the marine tanks ....total of 257lt.
For the desert trip...
Fully loaded and travelling on sand constantly...... say estimated consumtion of 22lt per 100.(25% increase on my test done above of 17.6lt per 100)
Therefore to cover 772 km of the desert section 170lt req.
Leaves 87lt margin...seems very generous,however with another 150/200 kg on board the base calculation of 22lt per 100 may end up higher.

Did another run last week around Mt Cole close to fully loaded and got 17.9lt per 100...no sand, no low range and 36psi (pressures will be lower on the actual trip which has no track....so 22.5 lt per hundred good starting point.

That's fair bit of detail ...cheers joe

FollowupID: 371228

Follow Up By: GO_OFFROAD - Monday, Jun 13, 2005 at 22:44

Monday, Jun 13, 2005 at 22:44
Something the "doomsdayers" here havent considered is that the vehicle was pretty much carrying the weight on its medium spring rate already, just sitting down slightly in the rear, so the polyairs have helped with this, and will be able to be adjusted, to less pressure as fuel, water food, and beer are used out of the vehicle, meaning the car wont be stuck with the heavier spring rate.

The Bilstiens certainly help with the polyairs, as I wouldnt suggest them to anyone with anything but the velocity controlled Bilstiens, as they do help prevent the bounce bounce bounce of the expedential spring rate air bags provide, better than other shocks IMHO.

I have seen the nipples break off polyairs, and seen a set burst in the rear of a rangie, jumping a dune at beachport, but not in recent years.
FollowupID: 371246

Reply By: old-plodder - Tuesday, Jun 14, 2005 at 08:26

Tuesday, Jun 14, 2005 at 08:26
I have a 96 Pajero, with King medium variable rear springs and air bags.

Originally put the springs in first, then the air bags about 2 years ago.

Have found the following:
1. The springs were because of heavier load when travelling, i.e. long range tank and carrying 100l plus of water when required. They took most of this load well, and being variable still gave a soft ride around town, well almost stock soft when empty.

2. Fully loaded run the air bags on 12 to 20 psi, depending on load. I would be concerned I had under rated spirngs if I had the air bags on full pressure alot of the time. Run 6 to 8 psi empty.

3. I always try and run as light as I can for fuel consumption, and just trying not to overload the vehicle.

4. Did find more bounce in the rear with the air bags, and stiffer on the bump. So when I replaced the shocks last time, went for some with less bump resistance, but more rebound stiffness to control the suspension. Gone to konis which I find are more of a rebound shock than some. I know, most shocks are stronger on rebound. I have also turned the adjustable konis up one notch. Evidently konis only adjust rebound, not bump. Found the previous ranchos RS9000 not so good as they adjust both bump and rebound in turning the one knob.
AnswerID: 115648

Sponsored Links