why are the tyre sizes limited on a 16" rim?

[De-lux]

Ok, so I'm in the market for either 33x12.5 or 35x12.5 muddies to go on the 16"x8" sunnies I currently have on my 80 series.

Am I missing something, or am I limited on the sizes I can get around this to the following, which are generally only available in metric sizes?


315/75R16 - 34.6 x 12.4 x 16
315/70R16 - 33.4 x 12.4 x 16
305/70R16 - 32.8 x 12 x 16
305/75R16 - 34 x 12 x 16

Is there a size I'm missing? Looking on ebay / gumtree etc for some cheap second hand jobbies and I can't find much :(


Sorry to beat up tyre topics again...

[McLarryBob]

I recently got some 315/75R16 for some 16x8 rims I had is the shed and the reason I got them and not 35x12.5R15 to go on the rims I had on the car was because the minimum rim with for 315 is 8" where as the 35x12.5R15 needed to be mounted on at least a 8.5" rim.
So if you want to keep it kind of legal you will need to keep it metric.

[De-lux]

hahaha what?

I think you've missed the point... the minimum rim HEIGHT for 315/75R16 is a 16" rim; obviously a 315/75R16 tyre will not fit on a 15" rim.

You can safely mount a 315mm wide tyre (or 12.5" in the old money) to a 8" wide rim. Many many people do it

[McLarryBob]

Yeah I get that. What I'm saying is I had 2 sets of rims, 15x8 and 16x8.
I was looking at either 315/75R16 for the 16's or 35x12.5R15 for the 15's. (Both pretty much the same OD)
Tyre manufactures say not to mount 35x12.5R15's on a rim, 8.5" is minimum width. I know this doesn't stop people its just the sort of little legal thing that you might get pulled up on or your insurance saying no. And I'm guessing if you managed to get a 35 or 33x12.5R16 it too would say min rim width is 8.5"
The 315/75R16 is suited for a rim width 8-10". So it can be mounted to your 16x8 rims without a worry about legality or insurance.


Anyway... Have a look on tyre manufactures websites. Most of them show all their sizes and have an outside diameter measurement.

[zookimal]

If you end up closer to a 33 then consider a 285/75 as well.

[-Scott-]

If you're happy with 285/75R16, I have my old STTs available (6 of them). Probably 10k km left in them, I can measure tread depth if you're interested.

Of course, they are in Adelaide...

[SIM79]

Am I missing something, or am I limited on the sizes I can get around this to the following,

16s have lot more size options than 15s do! You can get them in 29s,30s,31s,32s,33s,35s,36s,37s and a lot of them have 2 different widths to choose from.

Ok, so I'm in the market for either 33x12.5 or 35x12.5 muddies to go on the 16"x8" sunnies I currently have on my 80 series.

315/75R16 =35 x 12.5 x 16
305/70R16 =33 x 12.5 x 16


These are the sizes you want, no they won't exact, but if you measure most 33s or 35s they aren't exact either they are normally slightly smaller also.

[De-lux]

Thanks Sim, I guess I should be more precise... there are plenty available, but looking on Fleabay etc, most muddies are for 15" rims.

It seems 15" are waaaay more popular. :S

[Matt_85Lux]

Tyre manufactures say not to mount 35x12.5R15's on a rim, 8.5" is minimum width. I know this doesn't stop people its just the sort of little legal thing that you might get pulled up on or your insurance saying no.

The 315/75R16 is suited for a rim width 8-10". So it can be mounted to your 16x8 rims without a worry about legality or insurance.

35s or 315/75/16s are illegal on an 80series in Qld anyway so it isn't really going to matter if the rims are 8 or 8.5

[94lux]

Thanks Sim, I guess I should be more precise... there are plenty available, but looking on Fleabay etc, most muddies are for 15" rims.

It seems 15" are waaaay more popular. :S

Its because they're cheaper to buy in both the tyre size and rim.

[TheBigBoy]

Yep. Thats right. Its personal choice (if they fit on your truck). I had brand new pimpin 16" rims and tyres and didnt like them at all. Went back to 15's. The tyre shops want everyone to go to 16's because they are more expensive. They give the old speal "Its a better fitment from tyre to rim, and handle better in corners" which is total bullshit anyway as its un noticable between the 2 when fully aired. I found that the 16's being an inch smaller in the sidewall, made the sidewall alot stiffer. Where I used to air down to 12psi with 15's I had to go down to about 8-9 with the 16's to get the same result. I didnt like running them at that pressure with it always being in the back of my mind while doing everything. This wouldnt have mattered if I went up another 2 inches in tyre size. As it should be the same. But 35's is all I want for road/offroad use.

15" = same tyre as 16's, cheaper rims, cheaper tyres and better performance. My 2cents worth

[De-lux]

Hmmm... makes me wonder. I have my current tyres on ebay, but I was going to keep the rims and just slap some muddies on it.

Since my 80 series is a 1992 model I can fit a 15" rim. Perhaps I just get rid of the tyres & rims and get a new set of 15" rims and tyres together? Thoughts?

[McLarryBob]

If you already have the 16" rims wouldn't it be cheaper to buy just tyres to suit the rims than to buy new tyres and rims in 15"?
As other people have said, there isn't too much difference between the 2.

[MattGU]

If load rating is an issue the 16s are the go.

For what it's worth I run 285s on 16s on my 80 and find them great.

[nastytroll]

285/75/16 are about 33.4" measured. 16" tyres normally have more side wall plies which is the reason they are stiffer, I doubt that 1/2" of side wall makes all that much difference to the side wall flex compared to an extra ply or 4. I prefer 16" rims over 15's.

[TheBigBoy]

285/75/16 are about 33.4" measured. 16" tyres normally have more side wall plies which is the reason they are stiffer, I doubt that 1/2" of side wall makes all that much difference to the side wall flex compared to an extra ply or 4. I prefer 16" rims over 15's.

It does. Its been proven with tests of footprint size on paper. But yeah, its to with the extra half inch AND the ply's.

[Matt_85Lux]

The tyre shops want everyone to go to 16's because they are more expensive. They give the old speal "Its a better fitment from tyre to rim, and handle better in corners" which is total bullshit anyway as its un noticable between the 2 when fully aired. I found that the 16's being an inch smaller in the sidewall, made the sidewall alot stiffer

The reason 16s are dearer than 15s at the tyre shop is due to 16s costing them more to buy aswell, the profit on the 2 is usually roughly the same. So it isn't really any difference to them if you purchase 15s or 16s. Also if the sidewall is stiffer then there is less flex and therefore there will be better on road handling.

[own81]

what size is close to a 32 on a 16in rim?

[De-lux]

275/75R16 is what my HZJ80 had on it which is about a 32" from memory

[-Scott-]

what size is close to a 32 on a 16in rim?

265/75R16 is generally considered a "32", although they're generally under 32" rather than over. They are also a very common size of tyre; I'd be surprised if any other 16" 4wd tyre had more variants (e.g. manufacturers and/or tread patterns).

[V.W.Dave]

what size is close to a 32 on a 16in rim?

265/75R16 is generally considered a "32", although they're generally under 32" rather than over. They are also a very common size of tyre; I'd be surprised if any other 16" 4wd tyre had more variants (e.g. manufacturers and/or tread patterns).

I have a new set of BFG A/Ts on my landy 265 75 16 and they measure 32.1 with the weight of the landy on them.