Tyres Chipping

sorry for the glitch, i'm having troublr with photo loading.

any help would be good, i'm using flickr to upload.

thanks

This should make it a bit easy to see what I'm talking about.

image by artheserenity, on Flickr

How old are these tyres Greg ?
They some of look hard and brittle.
Generally chunky offroad tyres can chip bits off if given a hard time to scale a track etc, sharp shale like road etc.
Some are worse than others from past posts I have seen in a similar vein.
What brand / make of tyre ?
Look a bit like Goodyear Wrangler Duratracs ?
If so I had these on the Ranger for a while, eventually going back to stock rolling dia and less aggressive AT.

G'day artheserenity,

If you've been travelling along rocky tracks, particularly going up steep ones, then chipping of the Cooper ST Maxx tyre is not unusual. Happens because of the big blocks on the treads and the forces placed on them crawling up the steep grade.

What you haven't told us is what pressures you have been using (can then comment whether too high or too low) and how long you've had the tyres (they become more brittle with age). The picture shows plenty of tread although the tyres don't look new - could be wrong with this assumption? A little more information might get you better responses.

Now for the diversity of opinions about the best tyre.......

Cheers and good luck with the feedback.

Rob

I always remember reading in one of the 4wd magazines where they went out in the desert on a test with Cooper Development engineers.

The engineer said that chipping of rear tyres was caused by rocks thrown up by the fronts.
IMHO it is always the rears that chip .
In any case the development Engineer from Cooper should know if anyone does.
Regard s Philip A

Provided your pressures are correct for the load, speed and type of terrain, I would say the chipping is more a characteristic of the tyre compound than anything else you might be doing. Chipping is very common with some tyre brands when off-road in the Pilbara and Kimberley regions of WA due to the very hard rock and the fact the way the stones break leaves very sharp surfaces. In times past they made spears out of the stuff. This phenomenon can be exacerbated in the wet when the water acts as a lubricant assisting the cutting hence chipping process. Bridgestone D697 LT tyres do not chip in my experience. Also looking at your picture slight 'feathering' is evident which may be due to low pressure or misalignment but it is unlikely this would cause the chipping. I disagree that rocks thrown up by the front tyres cause the rears to chip because I have seen plenty of front tyres chipped just as much as the rears. Also with a loaded vehicle the front and rear tyres hit the road surface a lot harder at speed than the force generated by rocks thrown up by the front tyres hitting the rears. 2WD hire cars (Holdens/Falcons) running passenger tyres in these areas suffer badly from chipping further indicating that the problem is usually a tyre compound that is too soft for the conditions.

Unless you've spun it, chipping is generally a result of running too much pressure. Not enough info to say yet though.

So what tyre are they Greg ??

I was thinking they looked like my old Goodyear Wrangler Duratracs.
Rob K mentioned Cooper ST Maxx ?

To me it looks like a scallop out of every second lug?
If so I would suspect too low a pressure/alignment issues.
Do these tyres "howl" at speed on the bitumen?

My truck spends a lot of time in W.Qld. breakaway country where sharp silcrete rock is encountered.
Edge bites are common, but not restricted to any inner/outer edge or particular tyre.
Mike

Hi Greg

Over the years, we have travelled many thousands of kilometres of outback roads and many have been very rocky and I always drop tyre pressure to 20 % of what I use on the highway, or around 28psi and of course my speed is then no more than 80 kph. And having said that, my vehicle is only ever used for when we go bush, so you can rate my tyre usage as around 90% dirt and 10% bitumen.

What I can tell you is chipping can be caused by a couple of factors, having tyre pressure far too high, or the brand of tyre that you use.

We have never had any chipping at all with Bridgestone LT 694 or the LT 697 over the years and even on our Toyo AT11 Open Country LT tyres. One brand that people rave about is the BFG and we had them on our camper and they chipped so bad after just one trip up the Birdsville Track that we gave them the flick and now have the AT Open Country on the camper and not one mark on them.

When I posted about the issue of the BFG's people responded about...tyre pressure , going too fast, being on the rear they pick up more stones and the usual reply's about just how good they were and it is just me .

Them there were a few that broke the mould and spoke honestly about the BFG and they had the very same issue as me. Then low and behold at work a couple of months ago, a local came in and when I loaded a TV into his new Prado, I made a comment about how badly chipped his new BFG tyres were. The front were so badly chipped I could not believe it and that was from his Bridsville trip and he was less than impressed by the so called, super strong and so called tyre of tyres. This alone showed that even front tyres chipped for no other reason than....tyre brand.

So far I am very impressed with the new Toyo's and one thing I have now noticed, is that I am seeing more and more fitted to vehicles now.

So the Moto of the story is....do not let all the expects tell you it is the way you drive....it is your tyres.


Cheers



Stephen

Back when we lived down the Diamantina, and drove an 80 series, I always bought BFG AT's and used them for about 10 years.

Ran them at 32-34psi all the time, and never got more than 40K clicks out of a set of the 265.75R16's. The tread used to chip badly, no doubt accelerating the tyre wear. But their strength was "legendary", only one flat and no blowouts in often extreme conditions and a lot quicker than snails pace. :-)

As a 80% bitumen tyre you couldn't beat them, but not a good wearing off road one.

Bob

You have asked a question & several people have asked you relevant questions to help them assist you. It appears that you have ignored them, it is very annoying when people just post & run!

Hi to ALL,

Sorry for the late reply to your answers, I've been off-line for a few days.

As most of you have asked what pressures, how old etc. I try to answer with this one post.

Make - Cooper ST Maxx
Pressures - 20-24psi in rocky type conditions and 28psi on gravel roads. Road pressures depend on load, but in most cases 40psi
How old - 2yrs.

again, thank you to those that answered
Greg

That is not chipping....
This is chipping :(
Caused by the type of rocks, rear tyres only when travelling too fast and using too hard a tyre compound.

Cheers,
Peter
OKA196 motorhome