Dougal
Well-known member
- Joined
- Aug 2, 2020
- Member Number
- 2392
- Messages
- 96
Starting back in 1971 Landrover setup the Trans-Americas expediation with a pair of new Range Rovers. They drove from Alaska down through central and south America to Cape Horn.
The hard bit of course was the Darien Gap. 250 miles of jungle and swamp. They had 64 people total in the expedition. Some walking, some leading pack horses and many cutting tracks for the vehicles. Over half were evacuated for medical treatment during the Darien Gap.
There are some great videos on it well worth watching.
But the part that always fascinated me was the swamp tyres. For the Darien Gap they fitted "oversize swamp tyres" which proved a disaster. Instead of providing the necessary flotation to get through the swamp they just balled up with sticky jungle mud and started breaking differentials (spider gears) and axles at a rapid rate. By the time they got through to a clearing to camp out, make contact with Landrover and come up with a better plan they had broken 9 differentials, had one vehicle with 2 wheels driving towing the other vehicle with 0 wheels driving. That's the first picture below.
The lads in Solihull then took their own rangerovers, fitted the same oversize wheels, overloaded them the same way and drove around their test tracks. Finding out that yes they were also breaking diffs and axles.
Plans were changed, instructions sent to reduce vehicle load and replacement axles sent over more normal sized tyres. These worked and with a third vehicle (well used Landrover series 2A) they were able to make it through. Still to this day being one of the only motorised expeditions to make it through.
Since I first heard about this I've been fascinated by what these swamp tyres actually were and what size they were to cause all these issues. These pics show what I've found:
These vehicles still exist. Well the two rangerovers do. The Series 2A was already badly beaten and had no brakes. It was gifted to a local dignitary at the end of the gap and promptly crashed.
The rangerovers were later restored though which has destroyed some of the original evidence. For example they replaced the guards which were cut to clear the ~33" swamp tyres with original uncut guards. Looks like they were also restickered and redented but went on publicity tours afterwards before ending up in museums like Dunsfold where they are shod with the road going Firestone Town & Country rubber used on the road touring sections.
The 12-16.5" tyre size used is basically unheard of for 4x4 use now. It's pretty common for skid-steer loaders and agricultural equipment.
The hard bit of course was the Darien Gap. 250 miles of jungle and swamp. They had 64 people total in the expedition. Some walking, some leading pack horses and many cutting tracks for the vehicles. Over half were evacuated for medical treatment during the Darien Gap.
There are some great videos on it well worth watching.
But the part that always fascinated me was the swamp tyres. For the Darien Gap they fitted "oversize swamp tyres" which proved a disaster. Instead of providing the necessary flotation to get through the swamp they just balled up with sticky jungle mud and started breaking differentials (spider gears) and axles at a rapid rate. By the time they got through to a clearing to camp out, make contact with Landrover and come up with a better plan they had broken 9 differentials, had one vehicle with 2 wheels driving towing the other vehicle with 0 wheels driving. That's the first picture below.
The lads in Solihull then took their own rangerovers, fitted the same oversize wheels, overloaded them the same way and drove around their test tracks. Finding out that yes they were also breaking diffs and axles.
Plans were changed, instructions sent to reduce vehicle load and replacement axles sent over more normal sized tyres. These worked and with a third vehicle (well used Landrover series 2A) they were able to make it through. Still to this day being one of the only motorised expeditions to make it through.
Since I first heard about this I've been fascinated by what these swamp tyres actually were and what size they were to cause all these issues. These pics show what I've found:
These vehicles still exist. Well the two rangerovers do. The Series 2A was already badly beaten and had no brakes. It was gifted to a local dignitary at the end of the gap and promptly crashed.
The rangerovers were later restored though which has destroyed some of the original evidence. For example they replaced the guards which were cut to clear the ~33" swamp tyres with original uncut guards. Looks like they were also restickered and redented but went on publicity tours afterwards before ending up in museums like Dunsfold where they are shod with the road going Firestone Town & Country rubber used on the road touring sections.
The 12-16.5" tyre size used is basically unheard of for 4x4 use now. It's pretty common for skid-steer loaders and agricultural equipment.
