Farmers could be fitting tractor front tyres a third more often than they should, according to recent tests carried out by tyre giant, Goodyear.
And it’s all to do with incorrect wheel alignment, says Richard Hutchins, farm tyre specialist for the company.
With tractors travelling faster and spending longer on the road, the importance of having them correctly set up is even more important, both for safety and practical reasons.
Different factors can affect vehicle geometry – lack of maintenance, accidental damage and even general use. In some cases, tractors coming out of the factory can have some degree of error in wheel alignment, adds Mr Hitchins.
“All tyres should be lined up perfectly with the centre line of the tractor, and equally should be parallel with the road surface, too.”
The most common causes for misalignment are what’s called toe in and toe out. Toe in is when wheels are angled outwards (and lugs are worn on the outside) and toe out is when wheels are pointing inwards (with wear on the inside).
The result is irregular wear and more difficulty in steering straight. Plus extra stress on bearings and ball joints, leading ultimately to higher maintenance costs, explains Mr Hitchins.
Usually, it’s a case of using a tape measure to see how far out of alignment each wheel is, but this is rarely done, he adds.
Now, though, there’s a more precise way of measuring how far out things are. A laser wheel alignment system, made by Haweca, is already in use across Germany in both tractor dealerships and tyre specialists.
“The idea is that this will become an additional service offered by tyre companies and UK dealers, as it is already in the HGV market,” explains Haweco managing director, Peter Spraggs.
The procedure is simple, he adds, taking little more than 15 minutes to complete. First, the tractor is driven on to a pair of plates that allow each wheel to turn freely.
Laser heads are then positioned on the flat part of the wheel magnetically and the steering is set straight ahead. Two scales positioned in front and behind the tractor then indicate how much alignment is out.
“Depending on linkage design, adjustments can be made by altering the track rod. The laser continues to show the position on the scales, meaning the whole process can be done in a few minutes.”
The cost of having the tyres tested by a dealer or tyre specialist hasn’t yet been set. You can buy your own equipment for £3600.
This which sounds expensive, but the company points out that on a 200hp tractor, where front tyres cost in the region of £600-700, a misalignment of 14mm could cost nearly £500 a tyre, taking into account fitting and disposal fees.
So, on a large fleet, it shouldn’t take too long to recoup the cost.