BFGoodrich KM2 high tyre wear + pressures?

[Samblers]

Just done my first rotation on a new set of BFG KM2 Mud's at 7,700km in. Puma 110.

Out of curiosity i measured the tread depth. Unused spare showed 14mm. Slightly shocked/ alarmed to measure the tread depth at the front as down as far as 9mm on the inside edges of the fronts (10mm at outside edge)

Is this normal?

If so i give my tyres another 15,000km or so before they're buggered? :o

Is there something i can do with the tyre pressures to reduce wear? I run 36-38 fronts, 38-40 at rear, usually light to medium loading.

Interested in opinions,

Cheers, Sam

[Slunnie]

Not sure what your conditions are, but I get a fair bit of wear from laden touring on outback roads, and not much on sealed roads.

[Tombie]

Block set will drop tyres a couple of mm in months... It should slow down.

How is the wear across the tread?

[Trundle]

What's your centre tread like? Edge (both) wear usually indicates under inflation for driving conditions. Inside wear can be attributed to camber. This is all from memory of a chewing out I got from a company mechanic years ago, so may need to be verified by someone with more knowledge, but that is my understanding.
Cheers

[Samblers]

Block set will drop tyres a couple of mm in months... It should slow down.

How is the wear across the tread?

Typically about 2mm more wear on the inside edges than the outside for the fronts.

The rears are both fine - down about 1mm total across the tread.

[uninformed]

I know the OP probably has alloys, and I have no experience with Km2s, but I found 235/85R16 wore uneven and quick on stock LR 5.5 rims as supplied on 110s.

[Samblers]

What sort of life should be expected out of these KM2's?

Are my pressures good?

[Ringky]

Im now on my second set of KM2s in my work vehicle (a 07 hilux admittedly but similar kerb weight). I spend at least 40% of the time driving with a load on heavy gravel roads. Set number one lasted 75,000kms and I could have easily got 80 if I had wanted to wear them out completely. Set number 2 currently on vehicle has aprox 40,000 on them and looking like ill get 75K out of these too. I run mine at 32psi front 34 rear (rightly or wrong) but this seems to give even wear and a nice ride. I also get a wheel alignment done every 2-3 months as the road conditions on i drive on tend to send it out of wack. Just my experiences anyway
Cheers
Chris

[Jeff]

I have a set of 'road tyres' and a set of KM2s because I am paranoid about wearing them out. They are a pain to change and take up a lot of space in the garage, but I don't have to worry about wearing them out on the highway. I run 32 psi on road front and back, but that is lightly loaded, I haven't had a long trip yet, so they might change when it's loaded.

Jeff

:rocket:

[101RRS]

You should be looking in excess of 80,000kms out of a set of KM2s. Most people tend to over inflate their tyres and as such they wear first in the centres.

My personal thoughts are that your tyre pressures are a couple of PSI too much but I would let how your tyre wear patterns inform you on this issue.

I have KM2s on my 101 and run 30psi all round without any issues but for a 110 I would a bit higher pressure due to the higher speeds a 110 can maintain.

Garry

[Samblers]

What sort of tread depth remaining when worn? (approx)

Both my fronts were worn on the inside more which i suppose suggests camber? Perhaps i should get the tyres flipped on the rims in a year or so?

Here's my worn front (left, inside edge) vs new spare (right)

https://www.aulro.com/afvb/images/imported/2014/04/201.jpg

[numpty]

I know the OP probably has alloys, and I have no experience with Km2s, but I found 235/85R16 wore uneven and quick on stock LR 5.5 rims as supplied on 110s.

Recommendation for 235/85/16 is a rim width of at least 6"

I also run a set of road tyres on the alloys and a set of touring rubber on Disco steels for trips. I now have KM2's on these rims and will be setting off for a 7 to 8 thousand k run in July and will be interested to see how they go.

[uninformed]

Recommendation for 235/85/16 is a rim width of at least 6"

I also run a set of road tyres on the alloys and a set of touring rubber on Disco steels for trips. I now have KM2's on these rims and will be setting off for a 7 to 8 thousand k run in July and will be interested to see how they go.

yes indeed, but 235/85R16 is the metric replacement for the 7.50R16 and is common on 110s with stock rims.

[numpty]

yes indeed, but 235/85R16 is the metric replacement for the 7.50R16 and is common on 110s with stock rims.

Yes, 235/85 is near enough the same rolling diameter as a 750/16 but they are 1 3/4" wider.

So you're saying that the manufacturers advice is not worth following? To each his own I suppose. Bit like running tubelesss on LR tubed rims.

Stock rims on all later model 110's, at least from 2006, are 7" alloys which will fit a 235/85 comfortably, whereas 130's have 6.5" rims and these are fitted with 7.50's. ;)

[Sirocco]

I have about 60,000km on mine now. Most of that work (42,000) was heavily loaded on poor roads.

I would think 75-80,000km would be about average for most.

However, having said that, I think they are past their best around the 50,000km mark if used heavily.

G

[87County]

A lot of your reported tyre pressures are quite a bit higher than I use. I guess I enjoy the comfort of sub 30psi pressures more.

[Samblers]

Happy to drop the pressures and get better ride... thought this would make the tyres wear more though, not less?

[Jeff]

Happy to drop the pressures and get better ride... thought this would make the tyres wear more though, not less?

That depends on what you started with. All Land Rovers are created equal, but owners change them as soon as they leave the showroom and each one is different. Some leave them relatively standard while others add kilo after kilo and they should run pressures to suit. Tyre size may have an influence, as I run 33/12.5-15s, so what you run in 235/85-16s would be different too.

You can do the 'Michelin Test' where you set the cold pressure, then drive normally for a time and check hot pressure. If it has gone up 3-4 psi, all is good (I can't remember the exact number for LR), if the pressure has gone up more increase your cold pressure, if the pressure has not increased that much lower your cold pressure. Someone will surely correct me with the exact time and pressures, I have also seen it called the 'Pirelli Test'.

Jeff

:rocket:

[Samblers]

Yeah might do that, thanks

I'm not dripping with accessories, just bullbar at front and roof rack on top. Wife, 2 lodgers, the occassional takeaway coffee. I'm not driving round the Pilbara on gravel roads either. Hmm ...

:confused:

[benji]

If they're both worn on the inside, wouldn't that suggest to much toe out?

[noyakfat]

Remember that you are driving a permanent 4WD vehicle, so it's quite normal for increased wear on the front tyres from regular cornering (normal daily driver duties will do this). Not sure about the inside edges in particular, though...

Your regular rotations should help to even things out, but perhaps it would be worth a quick phone call to a tyre place?

[Samblers]

Will do. Re-alignment at the same time wouldn't hurt either.

I guess my original Q wasn't just related to wear on the inside edges of the fronts, but the magnitude of the wear overall, given the low km driven. It seems excessive.

Cheers

[gusthedog]

If they're both worn on the inside, wouldn't that suggest to much toe out?

Or that you spend to much time in shopping centres? :D:wasntme:

[rick130]

Never got anymore than 50,000km out of two sets of KM's and they were totally buggered at that but they were also a very different tyre.

[Samblers]

Never got anymore than 50,000km out of two sets of KM's and they were totally buggered at that but they were also a very different tyre.

different tyre to...?

[rick130]

different tyre to...?


KM2's

[101RRS]

Yes - KMs are a different tyre to KM2s

[joel0407]

I got 110,000km out of a set of KMs on a Troop carrier and that was carrying a fair amount of weight (work truck).

I have KM2s on the Disco 2 with about 7,000km. I've been searching for my tread depth gauge for the last couple of days to post pics of where they are at in comparo to the spare which is still new.

Happy Days

[Summiitt]

I decided to give a set of km2 a go on one of my 130s. I rotate and align every 10,000km, have tried all different pressures, but we will be lucky to get 45-50k out of them. Running along side a set of Mickey Ts MTZ on an almost identical if not heavier 130 puma ute and they are about half worn at 40k.
The ute with BFGs is doing forestry work so fast tar, fast dirt and shale/ granite trails... The tyre dealer who runs these tyres on he's f350 and recommended them is at a loss to the high wear, but is pretty sure it's the fast/windy bitumen that is killing these tyres, both utes run close to the GVM..don't think I will be buying another set for the premium price.

[Samblers]

I got 110,000km out of a set of KMs on a Troop carrier and that was carrying a fair amount of weight (work truck).

I have KM2s on the Disco 2 with about 7,000km. I've been searching for my tread depth gauge for the last couple of days to post pics of where they are at in comparo to the spare which is still new.

Happy Days

Post up your tread depth measurement when you have done them

Cheers

[Samblers]

I decided to give a set of km2 a go on one of my 130s. I rotate and align every 10,000km, have tried all different pressures, but we will be lucky to get 45-50k out of them. Running along side a set of Mickey Ts MTZ on an almost identical if not heavier 130 puma ute and they are about half worn at 40k.
The ute with BFGs is doing forestry work so fast tar, fast dirt and shale/ granite trails... The tyre dealer who runs these tyres on he's f350 and recommended them is at a loss to the high wear, but is pretty sure it's the fast/windy bitumen that is killing these tyres, both utes run close to the GVM..don't think I will be buying another set for the premium price.

Interesting. If mine carry on giving high wear on the fronts (especially on inside edge) I'll be rotating them and flipping them on the rims also.

Alignment check is being done now ...

[Samblers]

Alignment done. Toe-in was off by -0.5deg and -1.0deg

I asked if this was a lot and the tyre guy said "sh*tloads". I guess it must've been like that for a while. I also got asked if i'd been bashing the car around.

"well, it is a Defender..." :angel:

[rick130]

Alignment done. Toe-in was off by -0.5deg and -1.0deg

I asked if this was a lot and the tyre guy said "sh*tloads". I guess it must've been like that for a while. I also got asked if i'd been bashing the car around.

"well, it is a Defender..." :angel:

Defenders toe OUT, not in. ;) (Spec is 0-2mm toe OUT, but those values do seem along way out)

[joel0407]

Post up your tread depth measurement when you have done them

Cheers

Will do mate,

I'm still searching for my tread depth gauge. I put it somewhere safe, so safe, I can't find it. I even went to Super Cheap to guy another but they are $7 and since I already have one somewhere, I figured it was a waste of money. I might just use a ruler.

Happy Days

[Samblers]

Defenders toe OUT, not in. ;) (Spec is 0-2mm toe OUT, but those values do seem along way out)

Umm, yeah, toe out, oops

Guy said 15 minutes is about 1mm. So i guess 1 degree is waaay out.

[joel0407]

It's alright everyone. You can stop helping me look now. I found my tread depth gauge.

So the undriven spare is a smidge over 14mm and 3 of the running tyres with just over 7,000km a smidge over 13mm. The 4th running tyre is on the passenger (left) side front and it's about right on 13mm (round abouts, in town).

I know a couple have posted and guessed your tyre size at 235/85-16. Can you confirm as different tyre sizes of the same brand and model vary greatly in construction. Just an example, 31.5x10.5R15 are 6 ply where the 245x75R16 that I have are 10 ply. The higher ply rating means less tread flex, this means less heat and therefore longer mileage. The lower ply ratings are however on the wider tyres which means for the same weight they have a wider foot print compared to a narrower tyre that has a longer foot print for the same weight. So as the wider tyre has a shorter foot print, this means less tread flex, less heat and therefore longer life. It's very hard to make head or tails of peoples comments on tyres and tyre life for particular brands without considering tyre sizes. For example the standard Disco 2 tyre size is 235X70R16 (6 ply) but many fit 245x75R16 (10ply). If you were to compare tyre life the 245x75R16 should greatly outlast the standard tyre. Its wider, larger diameter and higher ply rating every point that reduces tread flex which reduces heat and extends life. If some one was to replace a standard size tyre and change brands at the same time the later tyre would look ridiculousness better but be a product of the dimensions rather than the brand or model of tyre.

https://www.aulro.com/afvb/images/imported/2014/05/1323.jpg (http://s560.photobucket.com/user/joel0407/media/Disco/2CD97721-DF6F-43D7-A4E1-AB224183C284_zpszqqxfi6x.jpg.html)

https://www.aulro.com/afvb/images/imported/2014/05/1324.jpg (http://s560.photobucket.com/user/joel0407/media/Disco/D3B79177-E8CF-41F8-9AA8-AB2D90746F62_zpssf4zmcmu.jpg.html)

[rick130]

Further to Joel's post, tyre sizes can vary batch to batch, let alone between makes.
Just because a tyre has 235/85-16 on the sidewall doesn't automatically mean it measures up at that.

In another lifetime when I raced, the Dunlop race tyre blokes would run the stagger tape around the tyres and match them in pairs, they varied so much in circumference/diameter. IIRC in some cases by more than 1/2" and these came out of the same factory and were ostensibly the same tyre !
When running on an open wheeler that's huge.

These were English Dunlops (and IMO were ****) the Japanese factories are much more consistent, but they do vary.
One of the Japanese Bridgestone engineers reckoned one of the hardest things in the world was to make a tyre round too !

[edit] FWIW I've measured two sets of Maxxis 762 Big Horns in 255/85-16 and they all measured damned close to 33.3" diameter when running the tape around the circumference at IIRC around 20-25psi, which is bloody consistent.

[Samblers]

So the undriven spare is a smidge over 14mm and 3 of the running tyres with just over 7,000km a smidge over 13mm. The 4th running tyre is on the passenger (left) side front and it's about right on 13mm (round abouts, in town).

Given my measurement on the fronts for the same mileage (down to 9mm) i'd say youre doing good.

For ref, my tyres are 265/75/16

[101RRS]

BFG tyres tend to be smaller than advertised - my 315/75R16 are quite a bit smaller than advertised - supposed to be about 35" in the old size but in reality are about 34".

Garry

[joel0407]

BFG tyres tend to be smaller than advertised - my 315/70R16 are quite a bit smaller than advertised - supposed to be about 35" in the old size but in reality are about 34".

Garry

I have to totally disagree with you there mate,

It's pretty common knowledge that 245x75R16 will fit on the rear carrier of the Disco with out flipping the carrier but BFG KM2 in that size, won't fit without the flip.

Tyre width is another thing though. Manufactures seem to be a bit of a rule of their own. I don't think I have ever measured a tyre that was exactly what the tyre size. I dont really know what its supposed to mean. Is it the tread width that may extend to the side wall of the tyre. That would flatten out when defelated. Is it tyre width at the maximum buldge of the side wall which could vary greatly with pressure.

And this Tire Size Converter (http://tire-size-conversion.com/tire-size-converter/) says your tyres are only 33.4 inches.

It's calculated like this, 70 series is 70% of the width in side wall height so 70% x 315mm = 220.5. You have a side wall on the top and bottom so 2 x 220.5 = 441mm of side wall. Plus the rim of 16 inches which is 406.4mm. So 441mm (side walls) + 406.4mm (Rim) = 847.4mm or 33.36 inches.

Happy Days.

[joel0407]

Given my measurement on the fronts for the same mileage (down to 9mm) i'd say youre doing good.

For ref, my tyres are 265/75/16

It's still too early to tell if they are wearing evenly across the tread and as I'll rotate them every 10,000km I may never know.

I run them at 38psi, all 4. I know some people have different ideas on pressure front to rear but I'm happy with the way it handles with the pressure as is. I do drive a little hard some times and I like the firmer ride and less tyre roll in corners. They get let down to 25psi off road. I'd go lower on sand but just haven't been on sand yet.

The Disco weighed in at 2460kg before I fitted the roof top tent and awning. I'll be weighing it again soon as I'm loading for a trip to the Gibb River Rd.

Happy days

[101RRS]

BFG tyres tend to be smaller than advertised - my 315/70R16 are quite a bit smaller than advertised - supposed to be about 35" in the old size but in reality are about 34".

Garry

ooops my mistake - typo alert - should have said 315/75 R 16

[joel0407]

Hey Garry,

Even though you made a Typo and changed your tyre size to 75 series. That's still only 34.5 inches. At that size it doesnt take too much pressure change to make 0.5 inch of differance.

Happy Days