Tractor Tyres

[jed the spread]

very high traction loads and low-slip

Like tarmac....?

*chuckle*

jed

[Roving Rich]

Well I remember Hafflingers running with "dumper" truck tyres years ago and amazingly capable in the mud when all else had bogged down.
For the muddy terrain you talking about they sound just the job.
Hell you could practicaly swim through like a paddle steamer !

Cheers
Rich

[silverbullet]

very high traction loads and low-slip

Like tarmac....?

*chuckle*

jed

C'mon fellas, not exactly a fair comparison is it? Sticky wide slicks on dry smooth tarmac maybe, but most ordinary road tyres slip to a degree under acceleration, braking and cornering loads.

It's not the same as being wheel-bound, in a reduction gear and wondering why the clutch has just gone pop or a CV let go.

IIRC in 1970 the famous "Darien Gap" Range Rovers repeatedly suffered exploded diffs, largely as a result of oversize mud-tyres being used in bog-down conditions. Lots of V8 torque (~200lb.ft) and an 11" clutch but nowhere for it to go when the wheels became stuck fast...

LSD rear diff and centre locker plus low-range transfer box completed the spec. All standard equipment for a 1900 kg 4x4 before expedition equipment and crew were on-board.

[rollercoaster]

Thanks, I know nothing of Land Rover/ Range Rovers,
My formative experience being buying one at an auction when quite inexperienced,
It drove through but must have been in second, when I got in it first was broke, so was reverse,
as I pulled away smartly in second the chassis broke in half, due to it having rusted away,
still it made it easier to get the gearbox out...

But hey, Darien Gap Range Rovers, made interesting googling,
classic mix of british motors and military officers on "expedition"
here is a snippet:


Blashford-Snell wrote a detailed promotional brochure on behalf of Rover, once back in the UK in 1972. It’s full of stirring passages like the one at the start of this article. Here’s another:

‘Our sweat-soaked clothes rotted on us. Leather equipment grew mould, even the best jungle boots available began to fall apart. The mosquitoes, gnats and flies became a constant plague… Clusters of aggressive and vindictive hornets nested in hollow trees and swarmed out to meet anyone who disturbed them. I have never seen insects so vicious. Within seconds a well-ordered column could turn into chaos under attack from hornets… Inch-wide centipedes and black scorpions also took their toll, whilst spiders as large as dinner plates were fearsome to behold.’

Range Rover project engineer Geof Miller remembers those hornets well. He was sent out to assist when rear differentials started breaking on a regular basis; he soon realised that the fault lay not with the vehicles but with the way they were being driven:

‘The problem was that the Army was overloading them drastically. They were still carrying all the kit they’d taken for cold-weather driving in Alaska. Then there were crates of stuff from sponsors, like Bird’s Custard, and even the officers’ full dress uniforms!

‘So the vehicles were full of spares and living gear, and then they’d put all the equipment like the inflatable boats and outboard motors on the roof-racks. I calculated that by the time they got on a 30º slope the overload on the back axle was something like 100% or more. They broke a rear diff in one vehicle, and carried on driving… and then the next thing to go was the front diff, so they would tow that dead vehicle with the second vehicle, until the rear diff on that one broke and then they had to stop and call for help.

‘It got to the stage where I just said, “Right, everything is coming out of the vehicles.” It took three flights of a little Beaver aircraft to take the excess baggage back to Panama City.’

Inappropriate tyres were another cause of diff breakages. Initially the Army fitted huge swamp tyres, designed to spread the load over soft ground. Not being trained in off-road driving, when their vehicles became stuck, the soldiers would sit there with the wheels spinning – until the rear diff got so hot it melted the Tufnol spacer washers inside, which led to excessive backlash between the gears, which resulted in broken teeth… In a misguided attempt to find more traction, the crews wrapped rope around the tyres, which then snagged on the disc brakes and ripped the calipers off.

[v-lux]

would sit there with the wheels spinning – until the rear diff got so hot it melted

So landie owners have been employing that tactic since the 70's huh!

[silverbullet]

So in conclusion: overloaded vehicles fitted with oversized tyres and an unsympathetic driving style leads to tears before bedtime.
Tractor tyres are best on a tractor