Rob's Home Page
ORD River 2010 (Triple J Cruise)
I have set up this web page to publish hard-to-find information as well as critical safety information.
Off-Road Tyre InformationTyre manufacturers typically publish
tyre load information for one pressure only, for example the
LT265/75R16E ('E' = 10 ply rating) has a maximum load rating of 1550kg
at 80psi. For off-road applications I can't imagine that anyone would
drive at 80psi. If your vehicle is crossing the Canning Stock Route or
the Simpson Dessert, then the tyre pressure would need to be more like
15psi to 25psi; pressures greater than this would almost certainly
result in you getting bogged.
I quite logically asked two different 4WD tyre manufacturer 'experts'
(three different 'experts' in total) for tyre performance data for
typical off-road inflation pressures of 20psi, 30psi, 40psi, none could
provide the data. In frustration I emailed the US headquarters of the
two largest 4WD tyre manufacturers and heard nothing in return. I then
set off on my own internet research activity, which took a total of
about 12 days of my time.
In my search for off-road tyre performance information, I came across
a fairly large amount of useful information that some people have
found difficult to absorb in one document. To help reduce this problem
I have broken the information into a number of smaller documents. I do
recommend that you read all of the documents.
In this document I discuss my findings on tyre performance for off-road applications.
I found that I had been operating my existing tyres well beyond their
design limits and I am lucky to not have been stranded on the Canning
Stock Route or in the Simpson Dessert with two delaminated tyres.
This document shows comparisons of two common 4WD tyres (LT265/75R16
and LT285/75R16) at different loads, tyre pressures and speeds.
This document contains charts of safe combinations of load, speed and pressure for a number of common 4WD tyres.
The document above on 'Tyre Performance Design Limits' explains how to use these charts.
document provides Load vs pressure data for most Light Truck tyres and
also provides the allowable rating increases for reduced speed.
The reader should be able to produce the Load/Speed/Pressure diagrams
for any of the listed Light Truck tyre sizes, similar to those produced
in the document above for the LT265/75R16 and LT285/75R16 tyres.
This document contains critical safety information as well as general
tyre information and links to useful tyre information web resources.
Information such as how hot can a tyre get before it is permanently
damaged and how long does a tyre last before it deteriorates and has to
be thrown away?