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4x4 Off Road Tyres & Wheels

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We tend to take 4x4 tyres for granted but their condition is essential to our safety. When off road, our 4x4 tyres can be the deciding factor as to whether we succeed or fail in our immediate objective.

There are a few important basic points we should be aware of about our tyres regardless of tread pattern or useage.

  • Tyres should be inflated to the correct pressure for the vehicle and load and checked weekly and before long journeys.
  • Objects stuck in the tyre tread should be removed as they can cut into a tyre under stress and cause deflation.
  • Uneven wear on a 4x4 off road tyre can cause steering and vibraton problems. The pattern of wear is indicative of the cause:
    - excessive wear on one side.......................wheel alignment needs adjusting
    - excessive wear in the tyre centre...............over inflation
    - excessive wear on both outer edges...........under inflation
    - excessive wear in patches around the tyre...unbalanced wheel
  • The legal limit for tyre tread depth is 1.6mm over 3/4 of the tyre tread.
  • Don't have different tyre sizes on the same axle (illegal) and don't mix cross-plies with radials (illegal on the same axle).


4x4 Tyre Sizes

Traditional (e.g. 7.50x16)
7.50..........the width of the tyre in inches
16.............the diameter of the wheel rim in inches

Note the ratio of the sidewall to the tread width is typically about 80% for older style tyres.

Modern (e.g.235/85 R16)
235..........the width of the tyre in mm
85............the % ratio of sidewall/height
R.............means the tyre is radial construction
16 ..........the diameter of the wheel rim in inches