Cooper Tyres

Standard for Coopers

Smoky,

What Coopers are you running and what tyre pressure along these roads? Also, can you clarify what you mean when you say the tyres started to break up? Did you have any punctures or blowouts and was the lug problem only apparent on the one tyre?

Sorry for all the questions but reason I ask is that we run Cooper AT's on our GU and trailer and are planning much the same trip as you did next year.

:o) MelissaPetrol 4.5L GU Patrol &
Camprite TL8 offroad camper

Greetings, sorry to side track but, I'm planning a trip from Perth over to Alice then up to NT back down to Gibb River road etc home down the coast in dual fuel inj.GQ Any good sites or maps for LPG availability or tips for fuel usage/saving
Cheers Scott

Met with a group at Birdsville recently that had just crossed the Simpson, 3 vehicles had Cooper ST's all had lugs missing from earlier in the trip ( not Simpson it seems) I also have passenger rated ST's no lugs missing as yet but pretty chewed after 3500km of outback roads & one stone fracture on 28psi. Mates BFG'S seemed to have weathered the trip better & no punctures !! It seems the Light truck rated ST's are the ones suffering from missing lugs, just an observation but then they do have a deeper tread than the passenger rated ST.

From what I have read, it seems the Copper ST's do suffer this problem of loosing lugs. It a common complaint.

You have traversed some fairly notorious roads however smoky.

A friend of mine got back from Cape Leveke (not sure of spelling) a few weeks ago. I'm not sure what tyres he had but I know they were not Coopers. He had 3 failures on his car and 2 on the trailer over something like a 1500km stretch including the GRR. Nasty rocks up there!

G'day Smoky,

What speeds were you running at? The higher the speed, the hotter the tyre gets and so the more pressure inside. Also - what is the wear pattern like on the tyres? Do you have less tread depth left in the middle of your tyres? If so - this is a sure sign that the tyre is not running flat on the road and is over inflatted.

Also - I haven't travelled those roads but are you sure your tyre pressures were appropriate? 45psi sounds way too high to me. I usually don't run with the same kinda loads as you were (cause I mostly travel alone and can get away without quite so much gear) - but I generally do not run my ST's at anything over 34psi Front and 36psi rear (for heavy loads). More normal tyre pressures (without load) would be 32psi all round.

On rough dirt roads I generally drop my pressures to 30 or 28 psi and reduce speed to 80 - 90 km/h. On sand tracks I generally run 18psi - but have gone as low as 12psi on Fraser Island in some really fluffy stuff! Reducing pressures allows the tyre to absorb more of the shocks from corrugations/rocks in the roads - but the tyres won't stand running at the same speeds.

My Cooper ST's have currently done 70,000 Km's trouble free (except a couple of minor punctures) and are heading for 100,000 Km's before replacement. There is some sign of minor stress around some lugs on the outside of the tyres - but considering some of the places I've been I'm not surprised!

Were the ST's you were running the LT version?

Cheers,
Prado Boy

there was 2 of us with cooper st's on our trip up north. We both lowered tyre presures. I was running 24-26 psi with a fair load and we didn't have any problems. No punctures and not ripped off lugs.
Like Prado Boy there are signs of stress around some of the lugs and I also have some chipping but I have seen the same on BFG AT's. I'll be buying them again.

Leroy

It sounds like an overheating issue. Heat builds up when there is too much flex, and is proportional to speed. Flex occurs when the tyre is overloaded, underinflated, or conforming with embedded rocks in the road. Excessive heat build up leads to breakdown of the tyre. I believe it can happen in any make, and can present as loss of lugs or a more generalised delamination (separation of tread from casing). It happened to me recently. Michelin tyre. Plenty Hwy. Deflation not apparent until too late. Several lugs missing, and severe weakening of side wall. Fixed the original puncture, re-inflated tyre, then loud bang which caused several bystanders to suddenly lighten their load ;-)Bob

What did you expect? Travelling those roads and distance you would have to be pretty happy to come away with a couple of lugs missing. I live in the Kimberley and travel the GRR frequently and by using appropriate tyre pressures for the load you have and keep the speed down, (yes sometimes 60 -70 kms instead of belting along at 100), you can minimise the damage.
I run BFG Mud Terrains and with 69,000 kms done there are some huge lumps of rubber missing and deep cuts in the tyres, but thats par for the course. I will see out this wet and will then be up for a new set. But guess what? No flats ever. So drive to the road conditions and weight of your vehicle and maybe you will do less damage. There is no easy formula but for your information the reason I picked the BFG was that the 285/75 16 LT had the second highest load rating @3305 available and max pressures of 65 lbs giving it what I thought the best chance of absorbing impact at low pressure and still being able to give good fuel economy at high pressure bitumen driving.
I only expected to get about 80,000 from muddies so I will be pretty close but for gravel, rock (GRR) and mud these tyres are great I couldn't be happier.

I got the same BS on BFG's (re speed rating) after I went back to the dealer for new tyres and told him (not complained) that they (BFG's) did not stand up to dirt roads.

I now have Dueller LT's that outperform BFG's 2 to 1 on dirt roads becuase they dont chip away.

Any very high mileage reports for any tyre is for blacktop use and may not apply to extended outback travel.

Sean