285 vs 265

[michaelgreeny]

Looking for a few opinions.

Currently running 295/70/17 Nitto Trail Grapplers. Looking at changing tyres to something smaller due to doing some fairly serious k's soon (Adelaide to Gibb River Road and back for a start)

Pretty keen on the K02's, just wondering what people think about whether the 285's are worth the extra cash over the 265's...local supplier has quoted $400 vs $339.

Will be used for everything from rocks, sand, mud, hills, etc.

On a '09 GU

Cheers fellas

[Clunk]

Depends on if you need that extra inch of diff clearance

[Plasnart]

I'd go 265s if majority was sealed or dirt roads where diff clearance isnt an issue as Clunky referred to.

[michaelgreeny]

Cheers guy, would the fuel economy difference be anything worth paying attention to or would it be pretty negligible?

[Plasnart]

You'd already be $240 in front with the 265s by the prices you quoted, and even though negligible difference in fuel economy between the two you'd only get better economy from 265s v 285s. I'd say go 265s if you're not scratching for clearance. Know how to vary tyre pressures for varying grip in different terrains.

[mudski]

Personally I would go the 285's. In my opinion the slight higher clearance will help especially if your in ruts etc etc. Last thing you want it to be dragging the diff centre on the centre of a rutted track. Thats a show stopper every time. I get it on the rear diff even with 315's as my rear diff is the larger H260 diff. Kinda wish it wasn't for this reason.
On the highway your fuel eco should be better with the larger tyre, more speed for less revs, but it will be opposite when in low range or slow stuff. But the difference either way would equate to sweet fa.

Your usage is rocks, sand, mud, hills etc. So to me the 285 is a no brainer. That little extra clearance over the 265 will help. Each to their own though.

[threedogs]

Not sure that statement about a bigger tyre give better fuel to be true.
When I put my 305s on my fuel figures go up.
Even here the best fuel figures are ppl running 265s.
A large tyre and small motor is more effort required to turn them.
Id go the 265 every 25mm you go up is only 12mm gain in clearance
so very minimal imo

[Cuppa]

For the Adelaide/GRR trip, whichever way you go I can’t see any advantage for 285’s over the 265’s. The choice is probably best determined by what other driving plans you have.

[happygu]

Not sure that statement about a bigger tyre give better fuel to be true.
When I put my 305s on my fuel figures go up.
Even here the best fuel figures are ppl running 265s.
A large tyre and small motor is more effort required to turn them.
Id go the 265 every 25mm you go up is only 12mm gain in clearance
so very minimal imo


TD, you have to remember that the larger tyre size will give you more distance for every rotation of the tyre, so in fact fuel consumption may not end up more at all.

In the OP, the tyre sizes talked about were 265 and 285
In a 265/70R17 tyre you may have a rolling diameter of around 804mm ( depending on brand, of course )
For the same brand tyre in a 285/70R17, you will have a rolling diameter of 832mm ....

What this means, is for every time your engine is running, for the same RPM you were doing on the 265 - on the 285 you will go 28mm further ..... that is why bigger tyres suck more energy out of the engine because the extra power required to turn the tyre a complete rotation, it means the car has to travel further.

This means you are going 3.5% further ( than your odometer is reading and what you were on the smaller tyres ), and if your fuel consumption has gone up less than that, you are actually in front ....

My fuel consumption probably went up slightly, at around 4 - 5%, so for the minimal extra fuel use, I get around 20mm more diff clearance with the bigger tyres.


My opinion is to go for the larger tyres, but for years and years, I stuck with original size tyres and went all over place.

[threedogs]

TD, you have to remember that the larger tyre size will give you more distance for every rotation of the tyre, so in fact fuel consumption may not end up more at all.

In the OP, the tyre sizes talked about were 265 and 285
In a 265/70R17 tyre you may have a rolling diameter of around 804mm ( depending on brand, of course )
For the same brand tyre in a 285/70R17, you will have a rolling diameter of 832mm ....

What this means, is for every time your engine is running, for the same RPM you were doing on the 265 - on the 285 you will go 28mm further ..... that is why bigger tyres suck more energy out of the engine because the extra power required to turn the tyre a complete rotation, it means the car has to travel further.

This means you are going 3.5% further ( than your odometer is reading and what you were on the smaller tyres ), and if your fuel consumption has gone up less than that, you are actually in front ....

My fuel consumption probably went up slightly, at around 4 - 5%, so for the minimal extra fuel use, I get around 20mm more diff clearance with the bigger tyres.


My opinion is to go for the larger tyres, but for years and years, I stuck with original size tyres and went all over place.

Ive never heard of anyone getting better fuel figures by fitting latger tyres,
as soon as I fit my 285 I get 15/100 when I had the OE 265s My fuel figures were 12/100k
I will go with a HWY pattern will be better than a MUD pattern for fuel and braking
Larger tyres play havoc with your braking ability as well
The patrol is designed to run best with gearbox and diff ratios on 265s
so by running 35s I travel further and get great fuel economy NAH wont work

[Clunk]

Ive never heard of anyone getting better fuel figures by fitting latger tyres,
as soon as I fit my 285 I get 15/100 when I had the OE 265s My fuel figures were 12/100k
I will go with a HWY pattern will be better than a MUD pattern for fuel and braking
Larger tyres play havoc with your braking ability as well
The patrol is designed to run best with gearbox and diff ratios on 265s
so by running 35s I travel further and get great fuel economy NAH wont work

Mic didn't say you'd get better fuel figures

[Winnie]

If you are doing a lot of highway kms you could possibly get better fuel economy with bigger tyres.
I know on our Simpson trip, Rossco was getting better mileage than AB and myself. Rossco was on 35s and AB on I on 33s. There are other variables too of course but shows that it is possible.

[Warwick89]

Ive never heard of anyone getting better fuel figures by fitting latger tyres,
as soon as I fit my 285 I get 15/100 when I had the OE 265s My fuel figures were 12/100k
I will go with a HWY pattern will be better than a MUD pattern for fuel and braking
Larger tyres play havoc with your braking ability as well
The patrol is designed to run best with gearbox and diff ratios on 265s
so by running 35s I travel further and get great fuel economy NAH wont work

I get about 1.5-2L better with 285s, second best upgrade I've done.

[MB]

Only my experience but our old DX4.2TD work ute with as standard 4.1 ratios seemed to get near 50kms per 80L tank further on the 'highway' when I fitted 35" tyres. Unfortunately never calculated stop/start and hilly country usage but in theory should have been worse than the 33" tyres I bought it with.

[Toy-Eta]

Looking for a few opinions.
Currently running 295/70/17 Nitto Trail Grapplers. Looking at changing tyres to something smaller due to doing some fairly serious k's soon (Adelaide to Gibb River Road and back for a start)

Pretty keen on the K02's, just wondering what people think about whether the 285's are worth the extra cash over the 265's...local supplier has quoted $400 vs $339.

Will be used for everything from rocks, sand, mud, hills, etc.

On a '09 GU

Cheers fellas

Hi Michael, old thread I know but interested on how the nitro grapplers performed when you had them? Looking at getting a set, have coopers at the moment but don't rate them. Did you have the 295s on sunraysias or stock alloys? Cheers - Westie

[Skitzyrex]

Hi Michael, old thread I know but interested on how the nitro grapplers performed when you had them? Looking at getting a set, have coopers at the moment but don't rate them. Did you have the 295s on sunraysias or stock alloys? Cheers - Westie

I've had a set of them for about 40k and find them to be a great tyre. I've used them on rocks, mud and sand and although you may have to drop a little more in sand (I run 12psi) they've been great for all. Probably only get 50k max out of them but that's fine with me.

[the evil twin]

Agree with TD... thats why you should change the diff ratios if you "permanently" change tyre size and also seriously contemplate rotor and disc pad selections.
IMHO for touring on formed roads and tracks I would choose the 265's... the extra 10mm of diff clearance won't matter squat really

Funny how people either love or hate Coopers.
I have never had an issue with them and when I change to another brand always end up going back.
I guess it is a 'horses for courses' thing.

[Toy-Eta]

I've had a set of them for about 40k and find them to be a great tyre. I've used them on rocks, mud and sand and although you may have to drop a little more in sand (I run 12psi) they've been great for all. Probably only get 50k max out of them but that's fine with me.

Awesome feedback skitz! They seem to have some pretty good reviews and IMO, if I can get 40-50k out of a set I'd be laughing at half the price of the big names. I don't know too many people that are *using* there big namers for distance's greater then that anyway. Cheers bud

[Toy-Eta]

Agree with TD... thats why you should change the diff ratios if you "permanently" change tyre size and also seriously contemplate rotor and disc pad selections.
IMHO for touring on formed roads and tracks I would choose the 265's... the extra 10mm of diff clearance won't matter squat really

Funny how people either love or hate Coopers.
I have never had an issue with them and when I change to another brand always end up going back.
I guess it is a 'horses for courses' thing.

I've given coopers a go twice, not gonna get me a third time. First lot had one peel like a retread at 110, was only 15k old and took out rear flare. 2nd lot had side walls break up and blow out again, not that old.

Bfg's I've had good runs with but seeing as I've got 6 to buy this time round, I'm willing to give the nittos a crack even if I can only get half the distance of a bfg. :)

[BigRAWesty]

If you are doing a lot of highway kms you could possibly get better fuel economy with bigger tyres.
I know on our Simpson trip, Rossco was getting better mileage than AB and myself. Rossco was on 35s and AB on I on 33s. There are other variables too of course but shows that it is possible.
As darren and i found out you cant compair different cars unfortunately.
His gu 4.2t used the same amount of fuel on 35's as my gq 4.2 did on 33's for the murry mouth trip..

From all experiences ive had and been told you roughly loose 1L per 100km of fuel per inch increase..

Im sure im too late but after doing Oodnadatta and the tanami, and talking to blokes fresh off the gibb id say go 31's.
There are no big ruts up here. All the tracks are well maintained now.
Its just corrigations the kill you so tyre pressures are far more important.

[DX grunt]

Don't know if you guys have them in the east, but Tyres and More in WA are having their May-July catalogue sale, and the BFG 265/75R16 123R, KO2, are on sale for $329 each.

When I got my first set of 6, two years ago, I got them for $330 a corner.

This may inspire a few, to consider. lol

Rossco

[TPC]

I recently had the same decision to make, for me it ended coming down to price as the 285's were dearer and I had to get 5 x 285's or 4 265's as I still had a good spare.
As Cuppa said, there is no advantage using the 285's on the Gibb River Road or offshoots unless you are really heading off the beaten track up there.

[CPOCSM]

I get about 1.5-2L better with 285s, second best upgrade I've done.

Same as above...getting a litre per 100km better fuel economy on the 285 v 265. I do like the better clearance of the 285 tyres also and JUST fit under the mudflaps...throw a stick or some mud up in the wheel wells and it does get pretty tight

[DX grunt]

Same as above...getting a litre per 100km better fuel economy on the 285 v 265. I do like the better clearance of the 285 tyres also and JUST fit under the mudflaps...throw a stick or some mud up in the wheel wells and it does get pretty tight

When I did my GCM upgrade the compliance plate says 265's - so I'm stuck with them. Having said that, I wouldn't change anyway.

I can sleep at night and and not have one eye continuously looking in the rear view mirror, when I'm driving. lol.

[stevemc181]

When I did my GCM upgrade the compliance plate says 265's - so I'm stuck with them. Having said that, I wouldn't change anyway.

I can sleep at night and and not have one eye continuously looking in the rear view mirror, when I'm driving. lol.


Pretty sure you can have up to a 50mm increase in tyre diameter on a 4wd over what the placard says.
The below is copied from the national code of practice and WA follows this as far as I am aware?
I also sometimes regret going up a tyre size, the small increase in clearance really isn't worth the loss of power and fuel economy.


The overall diameter of any tyre fitted to:
 4WD passenger vehicles specifically designed for off-road use (typically MC ADR
category). All wheel drive (AWD) vehicles including those AWD vehicles that may be
certified as MC ADR category, (also commonly known as soft roaders) are not
included in this category;
 4WD goods vehicles and their 2WD equivalents if the chassis and running gear are
essentially the same as the 4WD version (N ADR category); or
 any medium weight goods vehicle (NA2, NB ADR category).
Must not be more than 50mm larger or 26mm smaller than that of any tyre designated by the
vehicle manufacturer for that vehicle.
Note: Increases in tyre diameter are subject to compliance with all other requirements
specified under this clause (Clause 4.2 Non-Standard Tyres and Rims) and may
therefore be limited by other factors such as insufficient clearance.

[DX grunt]

Pretty sure you can have up to a 50mm increase in tyre diameter on a 4wd over what the placard says.
The below is copied from the national code of practice and WA follows this as far as I am aware?
I also sometimes regret going up a tyre size, the small increase in clearance really isn't worth the loss of power and fuel economy.


The overall diameter of any tyre fitted to:
 4WD passenger vehicles specifically designed for off-road use (typically MC ADR
category). All wheel drive (AWD) vehicles including those AWD vehicles that may be
certified as MC ADR category, (also commonly known as soft roaders) are not
included in this category;
 4WD goods vehicles and their 2WD equivalents if the chassis and running gear are
essentially the same as the 4WD version (N ADR category); or
 any medium weight goods vehicle (NA2, NB ADR category).
Must not be more than 50mm larger or 26mm smaller than that of any tyre designated by the
vehicle manufacturer for that vehicle.
Note: Increases in tyre diameter are subject to compliance with all other requirements
specified under this clause (Clause 4.2 Non-Standard Tyres and Rims) and may
therefore be limited by other factors such as insufficient clearance.

Thanks for the info. I choose not to check it out coz I'm happy with my 265's.

If it was mentioned to Clunk that DX grunt was getting muddies, I'd still hear his laugh from 300+ k's away, a week later. PMl. It aint gunna happen. lol.

[gubigfish]

Thanks for the heads up on Tyres and more DX grunt contacted my local store and they gave me the best price $359 balanced and fitted on 285/75/R16 KO2's