Not another thread discussing tyres-rim size, width etc

[disco stu]

I was very reluctant to start another thread on here about tyres, it seems there are way too many of them.

Been crook and for some reason hyper focusing on wheels and tyres after my recent thread. The car currently has 32x11.5 big horns that are getitng old, but still have plenty of life in the tread. I feel that size is too big for the vast majority of driving that I'll be doing, and likely overkill for most of the offroad I'll be doing.

Rims currently on it are 15", and it seems that there is a lot more choice in 16" tyres, so I was looking at grabbing some 16" patrol rims as they will fit on the gen 2 hub size

My thinking was grabbing something narrower and lower diameter to put on those rims. Around 30.5-31" diameter wouldn't lose me too much in clearance, and would make things a little easier on the driveline compared to 32" and the high gearing in the low range in the gen 2.
I felt something a fair bit narrower would suit my everyday driving much better and save a fair bit on fuel. I know going as wide as possible is the done thing, but I'm not sure its the right thing, especially for my use.

I've read a lot of the musings by Old Jack on here, and he really seems to know his stuff, and he seems to like the narrower tyres. I remember when I was young getting told to go narrower also. So I got thinking about the times when you need the extra gip-sand (which OJ has discussed a fair bit), mud and slipping on rocks. With the mud, there is the argument of cutting through with narrower tyres to hard ground underneath. With the rocks, I figure that wider also just means you likely have more tyre not really gripping due to the uneven nature under the tyre-its not like a nice flat racetrack where wider means more tyre on the road. Any thoughts on those musings?

Anyway, I was thinking an all terrain would likely do it in some size around 245-265 (possibly down to 235) and whatever aspect ration gets me up around 30.5-31" diameter (does anyone else absolutely hate that method of tyre measurement, I've got to calculate every single combination to see if it will get me what I want, as compared to diameter, width and rim size). Being perpetually broke I've been keeping an eye out for second hand, plus I've been reading a lot about best value tyres and in the cheaper outlay it looks like Comforser and Kenda have a surprisingly good reputation with those who have used them long term.

Anyway, I know tyres are done to death on here, but this didn't really seem to fit in an existing thread. Interested to hear thoughts on the musings

[Scrambler]

I have just gone down this rabbit hole for my diesel Gen 2.

I have driven more Land Rivers than Mitsubishis. The older cars all have thin 7.50/16 tyres, the older SWB 6.50/16. I have seen a 1950s leaf sprung SWB walk all over later model modified coilers. I came to the conclusion that modern wisdom isn't really that wise.

At the same tire pressure the narrow tyres will have the same area footprint as the fatties with less rolling resistance. The footprint is long rather than wide. There really aren't situations for recreational users where this is bad. If I was doing high speed running over a desert I'd probably want huge balloon tyres, like the Icelandic trucks run for snow. But skinny with appropriate deflation do everything else.

My GL diesel originally came with 235/75R15s. I've mounted Patrol split rims, which came with 7.50R16s. These are 210mm section width and are the same height as a 265/75R16. The car had been fitted with 265/70R16s when I bought it. The Patrol rims sit 15mm further out than the originals, 5mm further in than the wider rims, which places the outer edge of the tyre slightly further out than the original but still within the guards.

Fuel economy has improved from 13.3 l/100km to 12.1 l/100km.

The trouble with splitties (and a perverse strength) is the tubes. They mean more punctures. But they also mean easily repairable punctures while away from tyre shops.

I'd have loved to fit the Land Cruiser Ute tyres: 225/95R16s. But they are too tall to be legal on a Paj.

[Scrambler]

I should mention that I have a total of 8 splitties. I had 4 but had been quoted $300 to swap the tyres off my old LR rims. Instead I bought more split rims with tyres for $130.

Unfashionable thinner rims are frequently sold cheap.

If I were you I'd look at getting wheels off a wrecked NL GLS or Exceed. These are 16x7. Patrol rims are minimum 16x8. With the extra width and offset they aren't as neat and efficient as the real deal, and your 245mm tyres might not like them.

On the other hand, I have suitable steelies with nearly new 265/70R16s if you are interested.

For the sizes I use a tyre comparison website, saves using a calculator!

[Two Emms]

Many years ago (early 70s) I often saw my scout leaders little Suzuki with wide tyres vs landrover with narrow "pizza cutters"on the tracks in the NT. Boy do these tracks get muddy in the "wet" season ! When the mud was just boggy, there was no difference, with the zook floating over the top and the heavy rovers cutting down to the solid ground below. When the mud got bottomless the zook was often called on to help drag out a stranded rover. No the zook didn't become a long wheelbase but it was working really hard.

As to rocks, I have always liked the idea of standard width tyres as they just seem to be a bit more precise in feedback. Granted wide tyres seem to float over sharp rocks with less damage on occasion but I think this aspect is overstated. A well made tyre will take a lot of abuse whether wide or "skinny".

On a rough track which is simply corrugated and potholey, tyres with a decent sidewall that can be dropped in pressure will improve comfort by an incredible amount. No news to regulars on this forum but another consideration. This is moving the subject into profiles rather than widths , sorry!

I, like many others here, have been employed driving various 4wds in rugged country. Wide tyres have never been fitted to any of these. Original size tyres of a decent brand, in an AT pattern have taken me up just about any bush track whether rocky, greasy, (not bottomless bog holes of course) or under a couple of feet of snow. Would I have liked to be running wide tyres? On occasion absolutely yes. But I always seemed to get through.

So what do I use? On my paj, standard size ATs. On my navara, which was my previous bush tourer I had a set of standard size ATs for highway use and a spare set of bighorn MTs for the bush. This of course brings up the further complication, how far do you drive on the highway to get to the tracks and is the"bush" tyre safe on the freeway.

Arrrgghh. It's all too complicated!!

Just my 2 cents worth

[Scrambler]

Many years ago (early 70s) I often saw my scout leaders little Suzuki with wide tyres vs landrover with narrow "pizza cutters"on the tracks in the NT.

Thanks Two Emms. And Wow!

My family had an LJ50 Suzuki back in the 70s. There's no torque in the 3cyl 2 stroke motor but the ultralow gearing compensated.

I did a quick Google. The original rims are 16x4.5 inch. The original tyres were 6.00 inch bar treads. The "fats" recommended on the Suzuki forum are 235/75R15s. In short, the "fats" on the Suzi might well have been the skinniest tyres factory fitted to a Pajero.

[erad]

Vehicle designers always have a compromise when designing their products and of course there will never be a vehicle which precisely ft every person's requirements. Tyre selection is one such case - everyone seems to know more than the original designer...

Many years ago, I had a Cortina. I used to go skiing every weekend at Mt Baw Baw, and the snow there was always WET and heavy. In those days, there were no rangers telling you to put chains on or closing roads, and we used to drive as far as we could and walk the rest of the way. I always had 5 people in the car (sometimes 6) and the boot full of luggage. I had Michelim X tyres - the original design. From memory, the tyre size was 5.60 x 13. The tread was less than 100 mm wide, and it spread over a length of at least 100 mm.

All my friends had VW beetles with winter tread tyres on the rears (Oh how they must have over-steered on wet roads!). A VW with winter treads will climb a tree, but put it in snow 1 foot deep and the wheels will hang down until they hit something solid and it will drive. A foot of snow and they have nothing to grip on. But a VW beetle has a flat bottom and I used to come around a corner and see a VW sitting on its bum. I took great delight in driving past them, turning around and going back asking if they needed help and then turning around and passing them, leaving them and their passengers to walk the remaining miles to two to the top.

The reason I could do that was that my Michelins were cutting a narrow track in the snow and I was leaving a trail about 2" deep. The wet snow worked brilliantly with those tyres. Tie moves on and the next car I had was a Triumph 2000. Independent rear suspension, Pirelli tyres - Oh this car was going to be unstoppable in the snow. Wrong! The car was much heavier than the Cortina, the tyres were much wider and the first bit of snow or ice I came to, it just stopped dead. Useless, or relatively so compared to the Cortina. It took me years before I got anything vaguely like the Cortina. By then, Michelin X tyres were not available, and the Michelin XZX was nowhere near as baggy as the X was. Mind you, because of their bagginess, I managed to cut a few sidewalls on the Michelin X tyres.

Look at a wet road. The hoons use tyres so wide that the tyres have no hope of ever being able to pump water away from the centre of the tread. Europeans (Audi etc) use tyres with much narrower treads for this very reason. So it is horses for courses.

[disco stu]

Thanks all-lots of info here to consider!

That is a fair fuel saving Scrambler, better than what I expected. Still, ~13l/100km isn't that bad (kid at school was telling me that some of the patrol guys are using something like 27l/100km, he didn't say on or off road, but as we were talking economy in general I think he meant on road-that is just plain scary)

Two Emms-when doing those runs on stock wheels, did you ever find yourself really needing the larger diameter wheels for better clearance, or stock worked well enough?

I would be interested in those wheels Scrambler, depending on what tyres are on it, but I fear freight costs from where you are down to me would be an absolute killer

Reason I was looking at patrol wheels was purely due to availability. Bugger all Pajero's being wrecked compared to Nissan and Toyotas. There is one set of wheels in Nowra, but the guy is horrible at getting back to me so I've written it off

Brings up another thing that I was thinking, I do still want a reasonable amount of tire grip on the road. This car won't be dedicated only to touring or 4x4 but will be my daily run around and family car as well, so I don't want to go too narrow and lose too much grip when my wife goes fanging around a corner or brakes too late. I figured in that way that I was between 235 minimum and 265 maximum, with decent profile to bring it out to around 31" OD, LT construction, so it can go down in pressure when needed without problem.

You're friends must have hated you Erad

Lots of info to digest, thanks for the replies all

[old Jack]

Hi Stu,

My long held view is we have been sold the wide tyre myth since about 1980!

In the mid 80's I was driving for an outback safari operator in 55 and 60 series Landcrusiers, tyre of choice was Olympic Steeltrek 7.50x 16 on split rims, all vehicles were operated at 3000kg+ through Central Australia desert country, Cape York and the Kimberley. We did testing for Bridgestone on the new Desert Dueller 604 7.50R16LT on the 55 series and 31x10.5R15 on the 60 series, we had far less problems with the 7.50 x 16 than the 31 x 10.5R15 in regards to punctures and tyre failures but they were nowhere near as good as the Steeltreks.
Thankfully modern tyres are much tougher, can carry greater loads and handle all road conditions much better.

As far as road holding goes the width of the tyre is only part of the equation, tyre compound, tread design, sidewall rigidity and tyre pressures all determine how a tyre performs.
I run LT235/85R16 Cooper ST Maxx on my Challenger rather than the factory size 265/70R16 10ply, the Challenger weighs between 2450kg and 2860kg, and I do not have a problem either on or off road with traction no matter what the weather conditions or road surface are. I have high expectations of the tyres I use in regards to their on and off road grip, wet or dry, toughness, reliability and longevity, I do not drive slow or overly cautious but I do run low to mid tyre pressures compared to many. Around the city 32psi front and rear in the summer, 34psi in the winter. When we load up for a trip then the rears go up to 36ps for high speed bitumen. Once on rough dirt tyre pressures are run between 22 and 25psi, off road then 12 to 14 psi sand, 18-20 psi mud and rocks.

OJ.

[Two Emms]

Hi Stu,

I can't say that I gave a lot of thought to larger diameter tyres on the work vehicles because it wasn't an option. A bit like wanting to be driving the bosses comfy new (at that time a 120) prado rather than the new (at that time) v8 cruiser ute.

Looking back there would have been occasional times when larger diameter tyres may have made the going a bit easier but I always got it where it needed to go. Most bog standard 4wds are very capable if driven sensibly.

I agree with oj, we have been led to beleive that larger tyres are the answer to enhancing performance of any given vehicle. It's not that easy.

[erad]

.... But the big wide tyres look good! To hell with the practicality of them. One disadvantage of having a narrower tyre which bags out over a longer distance is that your alignment (toe-in at least) has to be very accurate. Mind you, if the camber is out a wider tyre will suffer worse than the skinny one.

[disco stu]

Yeah, looking good is really important-why else would God give me the body that I've got

Thanks OJ and Two Emms, some good info to digest there