Thread: BFG KO2 265/60/18

Originally Posted by LRD414

Hi mate, thinking of joining the fat tyre brigade hey.

For me, there were three reasons:
- zero rubbing in any situation or issues if vehicle drops to bump stops
- fit a fully inflated spare under vehicle
- stay close enough to factory size (775 vs 763 OD) to use one 19" as a 2nd spare in an emergency situation

I've since learnt that the bump stop issue is for older models anyway and I believe the later model bump stop would prevent locking of the wheel in the wheel well with 265/65/R18. However, at the time this wasn't clear and I suppose still isn't in that I haven't seen it tested definitively.

The deflated spare is not a show-stopper just a bit painful.

I have tested the 19" 2nd spare scenario and no errors thrown but not something I would run long-term. However, I am now favouring sourcing a cheap 18" rim and having the 2nd spare as a properly matching diameter to the main five, so that reason becomes somewhat redundant.

Since my selection I have been offroad with friends who run 265/65/R18 KO2s and I haven't detected any real world difference. Of course they have slightly better clearance and slightly better sidewall height so there will eventually be a situation where they are better off but not to date. Neither size stops cosmetic wheel damage.

What would I choose next time? Not sure really. Bigger is better in some ways but there doesn't seem to be much in it in my experience.

Cheers,
Scott

Yes Scott, the car is finally being transformed from an urban socialite into a tourer. Everything is happening within the next 2 weeks - I'll start a new thread with the details soon.

Thanks for explaining your reasoning behind your 265/60 choice. It's something I've been mulling over for the past few days. My main issue is the fact that I have only 4 Compomotives (as much as I understand the benefits of having a 5th one, I'm already spending over $16K on the car and had to make a compromise there).

I'm currently running OEM 20" Pirelli Scorpions - they're 255/50/20 from memory. This means that after I put the Compomotives on, these will become my spares. Not a big deal if I'm running 265/60R18's, however if I was to go with 265/65R18's the overall diameter difference between the two would be quite significant.

The question is - how to get around this problem?

In the end, I'll use 265/60's if I don't find a way around it - I know that I'll be very happy with that setup. But there's something about having a larger tyre that appeals to me, and if I can make it work, I'd like to give it a shot. Currently, two options that I'm considering are:

1. Buy an old 18" rim, like this one, for a spare (obviously would only fit on the rear axle, so some swapping would be necessary if a puncture happened on the front):
https://www.gumtree.com.au/s-ad/will...eel/1143128789 (cost: $100-200)

2. Replace one of the OEM Scorpions on my 20" wheel with a tyre which, when placed on a 20" rim, is sufficiently close to the overall diameter of the 265/65R18 tyre/wheel combo. For example, 275/55/20 (cost: $300-400).

Thoughts? Would you be able to sanity-check these two options, just in case I'm overlooking something?

Steven

Don't disregard the change in gearing in fitting 265/65R18 if towing. For 3.0 engines with 6-speed gboxes the larger size may be beneficial whereas the higher diff ratios fitted to 8-speed gbox vehicles could push the ratio too high.

Originally Posted by Smcconnell

1. Buy an old 18" rim, like this one, for a spare (obviously would only fit on the rear axle, so some swapping would be necessary if a puncture happened on the front):
https://www.gumtree.com.au/s-ad/will...eel/1143128789 (cost: $100-200)

2. Replace one of the OEM Scorpions on my 20" wheel with a tyre which, when placed on a 20" rim, is sufficiently close to the overall diameter of the 265/65R18 tyre/wheel combo. For example, 275/55/20 (cost: $300-400).

Steve,

Option 1 seems much better to me. Keep the 20's as a complete set with all same tyres, especially if they still have decent tread.

For your first spare you definitely want a matching diameter because you are far more likely to get one flat than two before the first is repaired.

If you think your trip(s) warrant a second spare, buy two cheap 18's. And then the 18" tyre selection is independent of the wheel situation.

Cheers,
Scott

Originally Posted by Smcconnell

Yes Scott, the car is finally being transformed from an urban socialite into a tourer. Everything is happening within the next 2 weeks - I'll start a new thread with the details soon.

Thanks for explaining your reasoning behind your 265/60 choice. It's something I've been mulling over for the past few days. My main issue is the fact that I have only 4 Compomotives (as much as I understand the benefits of having a 5th one, I'm already spending over $16K on the car and had to make a compromise there).

I'm currently running OEM 20" Pirelli Scorpions - they're 255/50/20 from memory. This means that after I put the Compomotives on, these will become my spares. Not a big deal if I'm running 265/60R18's, however if I was to go with 265/65R18's the overall diameter difference between the two would be quite significant.

The question is - how to get around this problem?

In the end, I'll use 265/60's if I don't find a way around it - I know that I'll be very happy with that setup. But there's something about having a larger tyre that appeals to me, and if I can make it work, I'd like to give it a shot. Currently, two options that I'm considering are:

1. Buy an old 18" rim, like this one, for a spare (obviously would only fit on the rear axle, so some swapping would be necessary if a puncture happened on the front):
https://www.gumtree.com.au/s-ad/will...eel/1143128789 (cost: $100-200)

2. Replace one of the OEM Scorpions on my 20" wheel with a tyre which, when placed on a 20" rim, is sufficiently close to the overall diameter of the 265/65R18 tyre/wheel combo. For example, 275/55/20 (cost: $300-400).

Thoughts? Would you be able to sanity-check these two options, just in case I'm overlooking something?

Steven

The other thing is,running LT BFG,you will have to be unlucky to get a flat that you couldn't temporarily repair with plugs and an air compresser.
In all the years,around 15,i have run these tyres i have never had a puncture while in a remote area.The only tyre damage in that time was a large coach bolt,and the tyre didn't go completely flat over night,and could have easily been repaired with a plug if needed.

In fact on the last desert trip,i took a spare carcase,not a complete rim.I have actually given up taking two spares on some trips,as i have never used one.

Maybe i have been lucky.Keeping tyre pressures correct is important as well,although i get a bit slack at doing this at times.

I also replace tyres before they are completely worn out,i find with our work vans,as soon as the tread depth gets low we start picking up screws,pop rivets,etc.

Don't get me wrong,you still have to be very careful,as tyre issues can be a show stopper.

As for 265/60/18,they are OEM size for some Hi lux,prado and Paj models ,so are fairly common.

I would take the 19",and forget about it,unless you can pick up a single GOE from somewhere.Using an OEM 18 is a pain as you may have to do some tyre swaping,as said.But then again,i recon most tyre failures are on the rear,particularly the rear left.

Good luck with your decision.

Originally Posted by Graeme

Don't disregard the change in gearing in fitting 265/65R18 if towing. For 3.0 engines with 6-speed gboxes the larger size may be beneficial whereas the higher diff ratios fitted to 8-speed gbox vehicles could push the ratio too high.

going from 60 to 65 aspect on a 265 tyre is a net 3.5% increase in overall wheel diameter. would that make a notable difference in drive-ability (or towing) given the torque we produce and the efficiency of the ZF gearbox's?

see pic below

Originally Posted by BrianElloy

going from 60 to 65 aspect on a 265 tyre is a net 3.5% increase in overall wheel diameter. would that make a notable difference in drive-ability (or towing) given the torque we produce and the efficiency of the ZF gearbox's?

see pic below

of the two tyres.

And if you want to get pedantic,if the tyre starts with 12.5mm of tread and you run it down to 3.0mm,the 9.5mm is not far off the difference of aspect ratio(60 verses 65) for the 265 size.

The 275/55R20 in my 4.4 TDV8 L322 with 8-speed and high ratio diffs is too high to tow my 2.5T van in top gear unless the speed can be kept right up to 100 kph. It's diff ratio is higher than that in the current 8-speed D4 but so is its torque. Getting back to standard ratio is one of the reasons why I'm considering a conversion to allow 18" rims to run LT265/60R18.

As the original size is 255/60R18, changing to 265/65R18 is a bigger increase.

I see there was a request for a photo of the silver rims on a white D4. This one is pre-bull bar.

P1060782.jpg