Suspension WDH and Airbags

[mrhappi]

Hi guys,

We're off to Tassie on Saturday (yes super exciting for The Happi's) to pick up our "new to us" Journey from @taz
We've been fortunate enough to also have a Hayman Reece WDH included as part of the sale but I've never used one before.
Our Paj has aftermarket springs and airbags.

My question for those with both airbags and WDH is... do you deflate the airbags when using a WDH? The Google's not helping so I was hoping some advice from the horse's mouth might help

 

[achjimmy]

@mrhappi I would just leave 5 psi in the airbags if your going to run the WDH . You don't need both. But unless you load up the drawbar a 16:49-1 would be okay behind a upgraded Paj without WDH too.

 

[Bushman]

The sort answer is no don't deflate the airbags, as they actually both do very different jobs. However the bags and WDH work well together, the bags should be used for the load already in the vehicle so should be inflated before the vans in on, then use the WDH to correct the added weight to the rear imposed by the van.

 

[mrhappi]

Cheers @achjimmy we currently drag around a 16.49-1 without WDH with no probs but the Journey's a little bigger (17.55.5SH) so think we definitely need that extra stability.

@Bushman I've read the bags inflated can work against the WDH. But like you've said I've also read they can complement each other. I'm interested to know if you're talking from experience.

 

[yabbietol]

Use the air bags and the WDH they work well together.
The airbags will reduce excessive up and down movement of your tow (they stiffen your suspension) and should be inflated to about 15 to 20 psi when hooked up. However, the air bag pressure is best determined by loading the tow, pump up air bags to about 15 psi and then putting on your caravan and checking if level, if not level then adjust air bag pressure up or down as required, once level then add WDH. You may find the WDH not really necessary, but unfortunately over 1.5 tonne AGM Mitsubishi recommend a WDH.
Air bags adjust your tows rear suspension (under load) and also act as dampers (in addition to the shockies), they are well worth having. I also note you are driving a Pajero, make sure you engage 4WD high range (4H) when towing, this will prevent excessive rear tyre wear (and as a bonus give better control).

PS the Air bags set up as above is also very useful when you unhook the WDH for off road or manoeuvring into a tight caravan park.

 

[Bushman]

Cheers @achjimmy we currently drag around a 16.49-1 without WDH with no probs but the Journey's a little bigger (17.55.5SH) so think we definitely need that extra stability.

@Bushman I've read the bags inflated can work against the WDH. But like you've said I've also read they can complement each other. I'm interested to know if you're talking from experience.

Yep I run airbags and the WDH on the Pajero, it can be a bit of a balancing act between the two, non towing the bags run around 10 psi as I have a storage unit with fridge slide in the rear, towing usually run 20 to 25 psi, the Pajero also have upgrade suspension (Old Man Emu).

Before the Expanda and the current van I had a Swan camper it was around 1650kg, the Pajero's standard springs would bottom out, the upgrade solved this, no WDH with Swan, had the same set up when I towed the Swan and Eagle prior to that with a R50 Pathfinder. both vehicle had the same drawer system in them.

 

[Axl]

The sort answer is no don't deflate the airbags, as they actually both do very different jobs. However the bags and WDH work well together, the bags should be used for the load already in the vehicle so should be inflated before the vans in on, then use the WDH to correct the added weight to the rear imposed by the van.

Totally agree with @Bushman I leave around 15-20psi in the airbags when using a WDH, the pressure I put/leave in the air bags is dependent on what weight I have in/on the Pajero and what extra weight I add to the draw bar of the Expanda.

 

[Bluey]

I agree with all above 20 psi in mine plus a hitch if you measure my car before van then after its hitched same measurement I love them prado and 1756-2outback

 

[mrhappi]

Thanks guys, some personal experience, thats what i was looking for!