Posted By Simon Walsh Grad IOSH
The organisation I work for has a fleet of HGV's and we have our own inhouse servicing and repair facility staff by qualified and experienced mechanics. Last week one of our HGV's was flagged down by a vehicle being driven behind and it was noted that the rear right near side wheel was loose.

The procedure we follow when replacing wheels is described below.

1. The wheels are selected with the right type/size and rated tyre with its condition and correct pressure checked.

2. The wheel condition is inspected and the seating area where the wheel is spigoted and the cone/spring cone faces are cleaned of rust and paint so as to make sound mating surface for the wheel to fit to its hub.

3. The wheel studs are lightly lubricated and the wheels fitted and the wheel nuts tightened in opposite sequence gradually and equally by hand to a final manufacturers torque setting.

4. The wheel nuts are left to settle and the torque setting re-checked again.

5. The vehicle is then road tested a certain distance at various speeds to settle the wheel stud and nuts together.

6. On return from road test and before the vehicle goes back onto the road all the vehicle wheels have their wheel nuts re-torqued again. This time the operation is checked by a witness to confirm all wheel nuts are seen to be checked. This operation is documented by the signing of a work ticket by both persons.

7. The work ticket is then returned to the workshops manager for checking and filing.

Vehicle maintenance is not my sphere of expertise so I would like comments as to whether this procedure seems adequate or is there something else we should, or should not be doing? Needless to say if a wheel had have come off the HGV the implications are very scary indeed.

Thanks in anticipation.

Posted By Alan Nicholls
Simon
My only question is Are your torque wrenches callibrated, so you know they are accurate?
The days of using a scaffold bar and wrench to crack the nuts are (should be) long gone.
Your check list is ok, dont forget any worn nuts or studs should be replaced as a matter of course.

Hope this incident was a one off. I know what its like first hand.
Almost lost a front wheel on a tractor unit was left with 3 useable studs all the rest had sheared off... Almost required a change of underwear!!!
Best of luck Alan N

Posted By Simon Walsh Grad IOSH
Thanks to all those helpful contributions, this will help me take the issue up with the workshops manager. Lets hope this prevents a similar occurrence.