stx D40 rear suspension

[Beergutz]

G'day,
I have an ST-X D40 with black widow camping drawers and snug top original canopy. It is my work truck and im constantly towing a 2200kg scissor lift all around NSW. While it tows like a champion im noticing the rear end sagging and would like some advice on which is the best option. Airbags?extended shackles? or complete lift kit? I occasionally get on the beach too. Have just got jayco expanda caravan and will be soon towing that all over the country side soon as well.
I have been doing reasearch but am a little confused as im reading some fixes affect handling and performance ect. Any help here would be greatly appreciated.

 

[rescue]

Not sure where you are located but given you're in NSW I'd be heading down to The Ultimate Suspension at Ingleburn. They did the suspension on my D40 and I' sure Ken or Brendan would be able to come up with the ideal solution for you.

 

[Matt76]

Hmmm, Id be considering airbags, but thats just me,

 

[Old.Tony]

I'm a mad tower as well, and have also been considering airbags in the rear. They should give me the flexibility to have a light load in the tub around town, or a heavy load (caravan, fifth wheeler) when I need it, with a simple adjustment.

2200Kg behind you should mean about 220Kg on the back (10%). That's over the 150Kg that the factory rear suspension is rated for. I think a visit to a good suspension place might be worthwhile.

 

[ants_oz]

I would not be relying on airbags alone, as in my opinion they don't provide the necessary load share - the only lift in the centre of the assembly, not on the ends of the spring pack.

I would be looking at good quality spring upgrade, and if you need airbags to supplement, then all good.

FYI - extended shackles are illegal. Full stop. They can't be engineered.

 

[jayk]

ive got airbags and new suspension in mine.

 

[4.8GU]

problem with airbags is as Ants mentioned and in these new utes the chassis is quite weak. We have probably all seen the pics of broken chassis due to overloading with airbags.

Also airbags on a factory suspension is a compromise because as the factory stuff sags more and more (and it will) you will be relying more and more on increasing air pressure in the bags just to stay at normal ride height and therefore increasing the harshness of the ride.

I can see the benefit of airbags but only on a suspension that is capable of at least holding the constant load of the car and accessories in the first place.

So imo get a suspension upgrade first. A good one will not compromise handling or be illegal and will in fact make the car more enjoyable to drive especially when loaded.

 

[coley350]

Gents, I a electricial contractor, i carry around 1tonne of gear on the tray of my king cab d40 all day every day. Its a big jack off ute tray setup fully inclosed with lift up doors, ladder racks, the works. I have 40mm longer shocks and springs in the front which lift the front 90mm from standard, as mine sagged when i put the steel bar and winch in, While the rear is stock springs with BOSS AIR BAG SUSPENSION with onboard compressor, tank and gauges.

With that load on the back the wheels nearly scrub on the underside of my tray, it will not carry the rated 1 tonne without an upgrade.

I run 100psi in the airbags all the time when loaded, The ride hight is spot on, and is a very smooth ride, not bouncy. But i must say it does track a bit in the steering, ie, you have to constently steer it, it will not sit on the road and track straight, you have to drive the thing which can get tiring on a trip. I have 60psi in BFG at's in the rear, 45psi in the front. Have to run these pressures or they chop out.

I will be getting some longer shackles next week to try and stop the tracking, I opted for this option after a mate with another d40, and another mate with a hilux got new springs in the rear and they were back jarring stiff.

 

[Beergutz]

I too am an electrician and can relate your weight issue. I carry all of my gear in the back as well which adds to the weight of the camping drawers. From responses i think i will go the new springs and maybe the airbags in conjuction. Great to have all kinds of feedback to help....awsome website. Thanks fella's

 

[Beergutz]

Just checked towing capacity and its 3000kg and 300kg over the ball, so that bit is all good.

 

[Old.Tony]

Don't forget - if you're towing 3,000kg and have 300kg on the ball, to subtract that from what you can shove in the tub. Normally about 810Kg for an auto dual cab, you're down to 510Kg while you're towing. I picked the auto Dual Cab because it has the lowest carrying capacity (the RX Single Cab manual has the highest tub capacity at 1,230kg).

If you guys are towing, you need to add 10% of your towed mass to what you're carrying in your tub and make sure you don't exceed your vehicle's limits. Apart from overstressing the vehicle, if you have an accident - even if it's not your fault - some investigator might spot that and give you grief over it in relation to your insurance, or even liability for the event.

Playing it safe won't hurt!

 

[banga]

I three am an electrician and carry about 600 kgs day to day. I looked around at all the options, and in the end took the cheaper way out and went to pedders and got three leaves added in each side and new shocks for $1350, which lifted the rear an inch above standard, front was left stock. Though this solution is working for me during the week, when the weight is taken out its a stiff ride and the kids hate it.

Now i am looking at putting a steele bullbar on the front which opens up a possible can of worms, cause if it sags and the coils have to be upgraded, they typically lift the front by at least 40mm which then makes the front higher than the rear, and the rear leaves apparently can't be reset to give more lift because the standard leaves are too short and run the risk of the shackle inverting.

So after all this i am now looking at going a tough dog 2 inch lift with 300kg to GVM springs which they reckon will give a decent ride when unloaded and also cope when loaded and if not i may add air bags later.

My advice is don't go the cheap option.

 

[jayk]

ive got both lift/new springs and airbags. im towing big loads ... up to 300kg ball weight. the springs are rated to about 150kg so i can hopefully use offroad too when not towing. done 10k sofar and all good. run the bellows at about 40psi.

 

[snowman]

I have had an extra leaf inserted into the rear leaf springs. I tow a Jayco 16ft caravan cost was only $330.00 works fine.

 

[debalan]

just got d40 so dont know how it tows just traded d22 which i towed 2 ton van sagged in rear so got h/r load distribution device cost $700.00 fixed problem towed great and sat flat

 

[Leprechaun]

just got d40 so dont know how it tows just traded d22 which i towed 2 ton van sagged in rear so got h/r load distribution device cost $700.00 fixed problem towed great and sat flat

The D40 does have fairly weak springs for Xtra comfort.
I found like most of the other guy's with upgraded springs that it's too uncomfortable when unloaded. I've removed the second stage load carrying springs and I'll fit 3" raised airbags in the next few weeks, so hopefully will give me the best of both worlds.

 

[Aussie Frontier]

Im trying to find a second set of stock springs so I can add some leaves from that to my current set. Shouldnt stiffen the ride too much but I have been warned its a pain in the neck to do.