Isuzu highlights body-building flaws

By: Steve Skinner

Date: 07.08.2014

A presentation at this year’s Comvec conference revealed some of the common follies when it comes to truck body building.

'Out of whack': Some of the basics of body mounts and chassis modifications are not being done correctly.

There is good advice out there on how to do the job right when it comes to putting a body on a truck chassis.

The truck manufacturers have their own guides. Isuzu, for example, has technical reference info for each of its model ranges, including trucks running on compressed natural gas (CNG).

Then there is the VSB 6 National Heavy Vehicle Modification Code.

So the recommended ‘do’s’ are available and commonly followed, but Isuzu Australia chief engineer of product strategy Simon Humphries is concerned there are too many ‘don’ts’ being practised in Australia as well.

"Some of the basics of body mounts and chassis modifications are still way out of whack in this industry and it concerns me," Humphries says.

He’s even seen a fire truck which was an accident waiting to happen: the body was attached in just six spots with the brackets too far apart, causing a lot of "bending moment" pressure on them; the holes were drilled too close to the flange (the top and bottom parts of a standard C-channel chassis rail) and therefore affecting structural integrity; and the bolts had virtually no extra thread.

"I think a decent stop or a bingle might have sheared those bolts," Humphries told this year’s Comvec conference in Brisbane.

"Or those nuts only had to come loose just a little bit — there’s not much thread holding them on — and then suddenly you’ve got a runaway body."

Humphries says while the official Isuzu body builders guide still rates U-bolts as the preferred method of attachment, it’s not his preferred method for Australia.

"The type of U-bolts and packers and attachments that they use in Japan is quite different to what we see in Australia where we prefer flitch plates, and to that end I'm going to have our body builders guide for the local market amended."

Check out more about body-building do’s and don’ts in the September issue of ATN. Click here to secure your copy now.