Can you get the axle loads recalibrated so the air suspension doesn’t overload itself?
My axle weights are
8500
8500
10500
8500
I’ve got air on the rear and as such I can only see on my dash weigher display what the loads are on those two axles. Quite often when running big (14t) machines it will overload axle 3 up to about 11500 and have axle 4 at about 6500. The machine needs to sit exactly where it does to fit within the foot print of the body so ideally the air suspension should carry a bit more load on 4. Now I think that this is a calibration issue rather than just overloading as I often carry a digger and dumper together, the digger which weighs about 9t sits right at the back of the body with the whole of the machine’s weight being loaded over axle 4 and it will still overload axle 3 and have capacity on 4.
I have a weight transfer switch to load up the drive axle for traction so the vehicle obviously can adjust the loadings, only it seems that it doesn’t want to.
Hi mate, it might be worth a phone call to Scania, we use Stansted and they’re pretty helpful with stuff like that, they adjusted my ride height for me, and my PTO speed.
Also have you ever put it on an Axle weigher type weighbridge ? do you know that what you see on the dash is accurate.
I’ll get them to look at Truck East when it next goes in, but I was wondering if someone could say for definite as sometimes they seem a bit slack at sorting stuff out.
I’ve only ever weighed it on a plate bridge, but I’m fairly sure it’s accurate. All plant is marked with weights on it and the load indicators usually tally quite well given the placing of the item. It’s a shame it’s not got weighers on all 4 axles.
Might be worth getting the tape measure and calculator out, seems the body/chassis setup and/or axle spreads make it impossible to load the 14 tonne machine within the axle limits. Scania have a guide to calculating the placement of loads on different chassis layouts from units through to 4 axle rigids, follow the link below and scroll to the last two pages
I’ve had 4 and six wheelers marked up with lines across the bodywork to indicate where to centre a load and stay within the limits, more axles and split loads make it harder to calculate but it can be done. My current motor is a 3+3 wagon and drag, prime mover is short wheelbase and plated for 26 tonnes, any load that puts gvw above 20tonnes will overload my drive axle but leave the others way under their plated weights. Adjustments to the air suspension won’t make any difference to the weight imposed on the axles, the only way to change the actual weight on the axles is to move the load that’s being carried so I end often end up with half the load on the wagon, half on the drag and cart 10 pallet spaces of fresh air around all day long.