Calculating axle weights

UK PROFESSIONAL DRIVERS FORUMS THE UK PROFESSIONAL DRIVERS FORUM (INTERACTIVE)
1

I know how to work out the axle weights for 2 axle lorry but how does the formula change regarding 3&4 axle lorries and measuring the wheel base ? Is it only possible to work out on a 3 axle lorry the combined weight of the rear 2 axles by takeing the wheelbase measurement from between the 2 ? Any ideas ?

2

I think without test loading a vehicle it’d be pretty difficult to have any accuracy especially with air sprung axles due to differing bag pressures between the 2nd and 3rd axles in the case of a 6x2 midlift type set up. Probably easier if steel sprung or both rear axles running the same bag pressure.

3

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Is this any use to you Dan? There is a rake of info and different set ups.

4

Thanks for the info I will have a look on there ,Dan.

5

This below from MAN gives the formulae for calculating axle weights including the all important theoretical wheelbase, which is necessary when dealing with multi-axle vehicles and particularly those which have bogies of unequal plated weights. … see page 28.

overlanders-handbook.com/lin … nology.pdf

6

AF1:
I think without test loading a vehicle it’d be pretty difficult to have any accuracy especially with air sprung axles due to differing bag pressures between the 2nd and 3rd axles in the case of a 6x2 midlift type set up. Probably easier if steel sprung or both rear axles running the same bag pressure.

i would’ve thought different size air bags will be used with the same pressure for different axles weights, so the mid lift will always carry the same % of the drive axle

7

Can’t really see that Stevie ,I’ve fitted pressure regulator vales to each air bag on a Granning converted rear lift as both axles were getting about 8/9 tonnes each and with 4 drive axle bags and 2 large bags on the rear lift spring .the bags were sharing the air supply.

8

Dan Punchard:
Can’t really see that Stevie ,I’ve fitted pressure regulator vales to each air bag on a Granning converted rear lift as both axles were getting about 8/9 tonnes each and with 4 drive axle bags and 2 large bags on the rear lift spring .the bags were sharing the air supply.

fair enough fella, it just seemed like the easy way to do it, but then again, i don’t design trucks!!