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Just to reignite this old fire, I will give you the latest update on my experiences.

After 12 months or more (probably closer to 2 years) or research, tests, trials and frustration, I now have fitted and tested some 325/85R x 16 XML Michelin tyres on 16' x 8' steel rims legally rated at 2100kg. These rims are fully DOT rated and approved and are therefore legal as far as my limited knowledge of these matters goes, and so long as you then have the upgraded tyre size approved for your vehicle should mean no infringement notices or insurance problems. I have the necessary Qld "Blue Tag" for all my modifications done to 406.

 I have followed the forums and looked at the alloys and flown in sample rims from the States, but for a number of reasons decided not to go with any of the available options. The fact that I need to keep my vehicle totally legal and comply with all insurance potential claim problems was the main reason, apart from my concerns about the alloys not liking the rocks too much when the Oka is up near max loading.

These rims are a special batch manufactured in China and imported into Australia by a vehicle component importer/distributor who carries the necessary insurances. Paul Nott is selling them and I have been trialling this first batch for two weeks now and have obviously only done a bit over 1000km on them. I have been running 900x16 XZL Michelins for about 5 years and have been happy enough with them, never experiencing any of the wandering problems others have mentioned. These bigger tyres are good, very nice in fact, and their performance in soft sand and really rough, washed out rocky tracks north and west of Cooktown last week was bloody impressive to put it mildly.

I am running 4.88:1 ratio diffs and L/S centres front and rear and I feel this combination is about as good as it can get. If you are running faster ratio diffs ( 3.6 or so) you may run into torque problems as these tyres are noticably larger in diameter. With the high profile offered by these tyres on these rims you get the best of all worlds with beautiful soft ride and large bagging potential when deflated for sand running. My vehicle weighs in around 5.5t and is very stable at all speeds with 55psi in the tyres.

On road noise is a factor, but as I have always run the lug tyres since buying the vehicle, I guess I have got used to it. With the windows up at 100km it is not a factor, and these larger tyres dont seem to be any different to the 900x16's.

The only drawback is of course cost. Around $1300-00 each new, but less than half that for good ex military available from Paul and a number of other sources. The eight I purchased are from 50% to 90% rubber and were $250-00 to $450-00 each.

Time and kilometers under the tyres will tell I guess, but for the present I think this combination will be hard to better, and at around $270-00 a rim the cost is acceptable.

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Xtra Tuff OKA rims;  made in Australia. swl 2t. legal ADR. available from Alan at OKA Parts Australia. We make steel tubeless rims because nothing else was strong enough or available. Currently making 16x7"  old 900x16 & new 255/100x16fit ++285/75x16. Also make 19.5 rims, as made by OKA. The Xtra Tuff rims use original OKA centres, also we can make centres. Check out post in bits for sale forum. Brett

I had the opportunity to have a close look at and a drive of John's #406 yesterday, thanks for taking the time to give me a good look at it. Congratulations on a beautiful job, the vehicle looks like new. Regarding the rims and tyres, I have been looking at various options for mine for some time and and have had several discussions with Paul K, the alloy's were never an option due to weight restrictions. However I was impressed by these steel rims with the xml's. Very little road noise, handled well when cornering and I didn't notice any drift. Seeing they tick the box's regarding weight carrying capacity and compliance I think they will be the answer for owners looking for larger tyres.

This Company in the US advertises ex military 325/85R16 XML Michelins with 85-95% tread for US $ 300- 350 each and they export. Might be worth a look.

How thick are the centres of the Chinese rims? I have a collection of rims with the centres torn out, too weak.  

Brett

I deleted a post by Peter and Margaret by mistake  Sorry!!  Thankfully I caught it before it disappeared and it said:

II considered the 325/85R16 XML Michelins for OKA196 in 2004.

They are stocked in Oz for the military 8x8s who use them on 9'' rims. They have a load rating of 2300kg at 65psi and are 984mm in diameter which is the same as the 11.00 x 16s.

In 2004 they cost over $1,000 each.

I subsequently saw some on a vehicle and while they perform exceptionally off road, the owner did say that they heel & toe badly and keeping wear even was difficult.

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Cheers Peter, OKA196 Motorhome. http://www.oka4wd.com/xt196.htm

Brett,

The centres are 10mm thick, and as can be seen in the photos are a fully die pressed centre. The rims have been load tested with the 325 85 R16 Michelin tyres as these are the only tyres in this size that they could find that could carry the load rating of 2100kg we asked for.

I'm not sure how these certification tests are carried out, but am told the wheel is loaded in a special jig and then run to the point of destruction. If the rim fails before the tyre it doesn't pass and can't be rated.

This option seems much more affordable for somebody like us with split rims. Can you keep us in the picture as how your test goes. Thanks.

After an odyssey of three blowouts and two punctures in four days, I had to buy new tyres which were difficult to get. I found two Michelin XZL 255/100/R16 in Botswana (some of the safari operaters use them on their Land Rovers) and got two more in South Africa.

Price was about 600 Euro each.

Tyre pictures are here ...