TRAINER’S NOTES
MEET MANDY Mandy Wannerton is the DAF Press & Demonstration Driver
UNDER PRESSURE B ack in November, I was lucky enough to head off to Goodyear’s factory and test facility in Luxembourg for a couple of days to learn more about the New DAF; not only did I come away from there with a rucksack full of knowledge on the XF, XG & XG+, I also came away with a revitalised appreciation for the humble tyre.
Now, depending on who you speak to, a tyre is many things. For instance, if you asked a mechanic, they’d say it was nothing more than an inflated flexible membrane. A geometrist would say it’s a torus, and a chemist well, they would speak in an alien tongue and tell you that structurally it’s a composite and chemically it’s a multiplicity of materials composed of long macromolecular chains (!) One thing is for sure, no matter how you describe this multilayered engineered rubber circle, it doesn’t just connect 52
DAF DRIVER WINTER 2021/22
us to the road it also provides cushioning, transmits driving and braking torque as well as producing cornering force, steering response and stability. Not only that, but tyres also have to provide adequate mileage and produce as little noise and vibration as possible. They also have to be durable, have the capacity to carry the load as well as being safe in all weathers. Yeah, tyres do a lot more than we give them credit for and as such, deserve more attention than the cursory “kick” we give them when carrying out our daily checks.
We check to see that the tyres and wheels are secure and have a tread depth of at least 1mm, we check there are no deep cuts in the tyre’s sidewall, we check there is no cord visible anywhere on the tyre and all wheel nuts are tight enough, we even check there are no objects or debris trapped between the twin wheels and of course we always check that the tyres are inflated correctly, don’t we?
You may be lucky enough to have an on-board tyre pressure monitoring system (TPMS) which will alert you to any changes in pressure or temperature, enabling you to sort a problem sooner rather than later; and new legislation means all new trucks registered from July 2024 will be required to have it.
Tyres also help with fuel and can have up to 2% impact on fuel efficiency. The more underinflated a tyre, the more it will distort. Not only does an underinflated tyre distort it also sticks to the road more which creates more friction and rolling resistance, so more fuel is needed; so the right tyre pressures are vital. Also, an underinflated tyre creates more heat and it’s this heat or vulcanisation which can cause the various layers of the tyre to separate and “burst”. Those shredded tyres we see laying forlornly on the hard shoulder or causing havoc as debris in
the road on the motorways, are often the result of underinflation. You won’t get that from a properly inflated tyre.
UK Construction & Use legislation banning the use of tyres over 10 years old on the front (steering) axles of busses, coaches and lorries, came into effect in February 2021 – so make sure you are aware of the date codes on your tyres, which indicate the date of manufacture.
At best an incorrectly inflated tyre will create unbalanced wear, at worst a blowout. Under inflated tyres increase vehicle damage and increase the risk of load damage and poor vehicle handling – notice your trailer crabbing in the mirrors? It could be a sign of an incorrectly aligned axle or dodgy tyre; either way it needs checking.
Stay safe now, Mandy x
