Isuzu D max

hi glenton
there seems to be a misconception that if you upgrade your rear springs that you then need to do a wheel alignment at the front this is not the case maybe if you have a 4inch lift done on rear it would have an effect on the wheel alignment but a moderate lift of upto 2inches wouldnt alter your front geometrics
sax suspension have a rear helper system take a look at their site
they also have new replacement spring sets for rear that seem to have a good reputation with reasonable pricing

saxsuspension.com.au
cheers

G'day Glenton
on a D22 navara i had i went the OME 400kg upgrade, worked well for me.

air bags you can change your ride height to what weight you are dragging around

G'day Glenton

The Isuzu Dmax will sink with a caravan ball weight and replacement with 300kg capability springs is a good idea.
I have a 2011 Dmax LSM ute and find/found it can take a load as it goes down to the load leaf at the bottom. This means you have on most vehicles very little travel left to absorb bigger bumps and this causes sudden stresses on susp and chassis.

I differ from MAZCAN's view. If you are going to add weight in the tub and also 250 kg to the ball then the front WILL raise from it's normal alignment position. This WILL cause some toe out and also negative camber of the wheels. How much depends on how far it rises.

To minimize the ball weight use a tow tongue which has the ball as close to the towbar as is humanly possible. Redrilling of the pin hole and/or a different profile will be better. This will give better sway stability, place less leverage onto the rear axle and suspension and also minimize the raise effect at the front.

Try and load the cvan so it is more balanced, this also helps, not too light though.

For towing I would replace the front and rear shocks for items which are more effective at dampening control because you are dealing with far more mass than before. If you ever have to suddenly brake or avoid you will be thankful you replaced the OE shocks. The OE shocks are appalling at dampening. They allow multiple rebounds instead of 1 to 1 1/2 and when compared to a BT50 they would register as unroadworthy.
Many call the Dmax susp Cadillac suspension for this reason. Very soft and baggy when going over gutters and cornering. Poor instantaneous directional control if required in an emergency.

If your front does raise more than a small amount 10- 15mm then be aware and keep a close eye on any feathering appearing on the outside edges of the tread ribs.
If it, does toe in will have to be adjusted to suit the condition/situation. This can easily be checked by placing two straight edges against the sides of the tyres above the bulge and measuring the distance fore and aft of the front tyres.
Cheers
Ross M

Hi glenton,

I have a 2011 D max, steel b bar, winch, and canopy. I also fitted an Ironman performance suspension with a 50mm lift. My " Dirt road " caravan has a ball weight when in travel mode is 260kgs. I also use an eazy lift WDH. ( would prefer not to. remove it when in rough terrain).
In the tub has aux battery, toolbox, generator and big engel as well as the usual stuff.
when fitted the lift kit got the front end aligned, and for some reason needed to get another done about 25000 K's later must of hit something as was way out on one wheel.
have dragged the van through dry /wet creek beds, strez track, Noccundra road , Odnadatta track, no real problems yet.
would have prefered to have ball weight bit less but the van was ordered for one vechile, that was sold and the Max bought. the weight tends to make Max porpoise a bit we towed a mates van 900k's for him , it had a 200kg ball weight and no WDH needed and no porpoise.
Cheers Warren

One thing everyone forgets is to weigh your 4x4 and if you tow; weigh it with what ever you tow connected.....

Most people would be surprised to find when loaded they are over weight and illegal.

A suspension lift will not give you extra weight carry capacity and the so called 200-400kg constant springs are a joke and mean very little in real world terms.

You can have very heavy spings that will give you standard ride height but the down side is when unloaded the ride will be very firm and uncomfortable.

Don't even thing of using air bags...... properly set up and balanced suspension will out perform a cheap shonky suspension set up any day.

In most cases with factory and most aftermarket suspension it's a balance between ride comfort, handling and weight carrying......

Ross there may be a reason why 4x4 utes including the have Isuzu have "Cadillac suspension"...... if they didn,t you would have 98% of owners complaining.

And as mentioned above dampener upgrades are a must.

Get some professional advice from a suspension manufacture like Lovell who have experience with upgrades and can make suspension for your needs...... don't go to ARB,TJM or any of the other 4x4 places for advise....... they only sell off the shelf "one size fits all" bits.

Every 4x4 we have owned and all the service vehicles at work have all had custom suspension set ups..... not off the shelf.

Do it right the first time.

I have a Mazda BT50 towing a Kimberley Kamper sport rv,springs sagged and when I sought advice from my Mazda dealer he advised strongly against airbag assist for the same chassis stress problems mentioned in an earlier post..instead he recommended IRONMAN helper springs,got on their website ,found what i needed $150 del. to my door in N.Q. in a couple a days .Took me less than an hour to fit and do the job very well..Hope this is of help ....Regards Jack

What great response and most welcome. One thing for sure the shockers are going to get upgraded. Have a set of Iron Man load assist and while they can be adjusted found they tended to distort the back half of rear spring. Ended up with poor tyre wear on rear.

Appears I need complete lift kit, although rear spring upgraded and shockers may do. Will take into suspension specialist, which one is another matter, depending who is in the local area. Noted that I need to be aware of off the shelf one size fits all as it appears what works for one does not work for another.

Been reading up on weight issue regarding vehicle etc and will have to make sure keep inside the design specs. Think I need to get all weighed when loaded etc.

Comments all appreciated and appears everyone has dealt with this problem at sometime. Just my turn.
Cheers Glen

Why ? Would you need to touch rear suspension with a moderate 400kilo load I am on my third Isuzu (previous two were 2.8 td 4wd doing Heavy farm work) has 100ks on clock usually has 600kilo in rear and then add 23' van, rear sits approx 20mm from bump stops and doesn't bottom out , take load of and springs rebound to original height only need to replace shackle rubbers, which I will do in next month or so (rubbers arn't worn out but like to run nylothan rubbers due continual heavy loads.
Isuzu suspension very is very strong and resilient.

No Mexican look, the suspension will bottom out when van not attached (weight distribution hitch also) if you attach humps etc square on at speed but that's just operator error if it happens.
Maybe the Isuzu suspension is a tad heavier than some others mine has just done 17,000. Around NSW and SA including Simpson

Wow suspension doesn't regularly hit bump stops in fact hardly at all once or twice in last two weeks when partner loaded Xmas plus shopping and even filled rear seat.(don't normally have anything other than coat, hat in rear seat for safety sake)
Been in transport of livestock local and interstate doing approx 170k/ annum for too long to not have safety and drivability at forefront of mind.
Not a farmer do not overload, ran ute and van over way bridge before trip GCM 5100.
Ute Alone 2450. Without roof load 60 and partner (shouldn't say will get killed) 63. Van 23' ATM 2556. Haven't weighed it on its own.

Setup drives, stops doesn't bottom out very nicely no need for suspension mods.
Did contract doing farm work with staff driving vehicles and delivering f/wood (hardwood) in evenings those two utes worked! Sold both at approx 380/400klm on clock one to farmer five hours away who lit stubble paddock and had to replace the ute he forgot in paddock

Hi Glenton

You may like to check the thread-: 96748- re the Super Springs I fitted to my 2011 Colorado.

I have had no problems with them and they are easy to fit yourself.

cheers
Ed

The manufacturers of our twin cab utes supply us with suspensions that will carry the designed loads. However they expect us to mount the load a bit further forward than the great loading on a tow ball.

What most people do not realise when it comes to the loading of out tugs is the effect of the weight on the ball. Measure the distance of the ball from the rear axle centre line. Compare that with the wheelbase. You will find that the overhang is approaching 50% of the wheelbase. So what is the effect of this? If you have a 50% overhang it will mean that for every 100 kg you load on the ball the weight on the front suspension will become 50 kg lighter. So where does this 50 kg go? If you remember back to our physics lessons on levers at high school you will realise that putting 100 kg on one end of a lever and 50 kg on the other end you will have 150 kg on the fulcrum. With our utes the fulcrum is our back axles. To put it another way, when you put some weight on a tow ball you add a load equal to 150% (or close to) on your rear axle.

Many of us know of the load de-rating that Nissan apply to their vehicles when we are towing. Nissan do not recommend that weight distribution hitches (WDH) be used on their tow bars. They thus supply the figures for the load reductions we should apply to our vehicles. Other vehicles are not exempt from the lever effects when you are towing. It is up to you to work out the de-rating for your own vehicles if you are not employing WDH.

If your vehicle is down at the heel and up at the front it is a sign that your rear axle is carrying a large weight. This weight is in all probability an overload on the axle.. Beefing up the rear suspension does not remove this overload, it just makes it look like you have done so. There are only two ways you can restore the over loading on your rear axle to be within the limits set by the manufacturer. One is to leave some of your load at home. The other is to fit a WDH. Beefing up your rear suspension just makes things look good, it does not make your vehicle operate within safe limits. If you use air-bags to beef up the suspension then there is a high possibility you will be another casualty with a bent chassis.

The following JPG is an actual demonstration of the effect of WDH that was given at a Melbourne caravan show

Thank you Peter D,
Great info wish I could have expressed it as we'll .
So why do people modify a vehicle when it is so simple stay within design limits or leave the load at home or buy a more suitable vehicle.
Use the vehicle hard but don't abuse it and it will go and go safely/economically