275/40/20 tyres on 8.5J wheel?

[Tsixty]

Just when I thought I had all my 20" T32 tyre wrangling clear in my head and I'm thinking about new tyres, another issue crops up. To recap, my van has 20" Zito 935 wheels and tyres are 275/40/20 106 front and back as the van was supplied to me, so all good there (I know many prefer 265/40/20 but the 275s are working perfectly well for me with no rubbing or issues on a 40mm drop).

I've only ever taken a front wheel off to check the load rating and it was clearly stamped on the back 900kg so all good there too. However, I'd never really taken much notice of it before but the front wheel I've had off is stamped 8.5JJ. Now (after some research) I understand the difference between a J wheel and a JJ wheel and I'm not particularly bothered by that. But a 275mm wide tyre on a 8.5" wheel? Everything I've read suggests that isn't recommended or even possible with some tyres.

I've never really noticed it before but the front tyre sidewalls do seem to 'bulge' very slightly more than the rears, although it is hardly noticable. I have a feeling (that will only be confirmed when I whip a rear wheel off over the weekend) that I'm going to find my van has staggered wheels (8.5 at the front and 9 or 9.5 at the rear) and I didn't know but the same tyres on both. It is a 4Motion so I understand why you would want to keep the tyres the same front and back but surely because of that you would have kept the wheels the same too? I suppose that then begs the question can you put a 9 or 9.5 20" wheel on the front with a 275/40 tyre without issue? Or do I look to get narrower fronts that match the rear's circumference as best I can and hope that doesn't cause a 4Motion issue?

Just when I thought I had it all clear in my mind I'm stuck again......

 

[The Van Cave]

If you want to match the circumference of the 275/40 on the fronts (yes, they are too big for the 8.5" rim) then you can try a 245/45. These are readily available in the required load rating for a T32 and work much better on the 8.5" rim. Check out the size difference on willtheyfit and you'll see they're very close.

It'll be interesting to see what width the rear wheels are.

 

[Tsixty]

If you want to match the circumference of the 275/40 on the fronts (yes, they are too big for the 8.5" rim) then you can try a 245/45. These are readily available in the required load rating for a T32 and work much better on the 8.5" rim. Check out the size difference on willtheyfit and you'll see they're very close.

It'll be interesting to see what width the rear wheels are.

Thanks, also interesting to see how a tyre fitter got a 275/40/20 on an 8.5J rim can't have been easy surely?

 

[T6ARF]

I’m in the same situation @Tsixty.... bought my van with 20” alloys and 275/40 tyres.... 8.5j fronts and 10j rears. I just accepted the extra bulge on the front with the staggered setup, until recently when I had my van dropped from 40mm to 65mm and the fronts started catching on the inner wing, so I started considering a ‘thinner’ tyre?

Like you say, when you think about it, why would anyone fit a tyre that is well over 10” wide on to a wheel that is only 8.5” wide? Anyway, I started doing my own research with the help of the website willtheyfit as @ChrisR says and the 245/45 total diameter is 728.5mm with a sidewall of 110.25mm compared to the 275/40 which is 728mm and 110mm, so you’re as near as dammit there.

With you having to think about T32 load rating and also 4motion as well, this has to be your best option.... be interesting to know when you find out how wide your rear wheels are?

My van is a T28, so the load rating is lower and no worries about 4motion. My route is going to be to change my fronts only to 235/45 with the 275/40 on the rears (as these sit well on the 10” wheel). The total diameter for the 235/45 is 719.5mm with a sidewall of 105.75mm.

Hope this helps you or somebody else!?

 

[Tsixty]

@T6ARF that helps very much thanks, if nothing else it confirms the conclusion I was already coming to. Fortunately the new tyres that I had decided on are available in both 245/45/20 and 275/40/20 sizes. the smaller are 103 the larger are 106 but I don't think that will matter, the fact that they are both 103 and above is what is important. As you say a less than 1mm difference between them so shouldn't cause any 4Mo issues. Just need to get a rear wheel off now and see what it says on the back of it. Watch this space.

 

[Andysmee]

There is a particular vendor on here that continues to recommend 275 on 20", in spite of the above, as if the wheel width is of no consequence. So there will be many vans in circulation with staggered alloys and oversized tyres on the front. I don't get it, personally.

Try this visualisation: 20in wheel tyre width options

 

[Tsixty]

There is a particular vendor on here that continues to recommend 275 on 20", in spite of the above, as if the wheel width is of no consequence. So there will be many vans in circulation with staggered alloys and oversized tyres on the front. I don't get it, personally.

Try this visualisation: 20in wheel tyre width options

Tbh I don't really care that much how it looks, but it has to be safe. There is no issue in my mind fitting 275 width tyres on 20" wheels as long as the wheels are correctly matched which means 9.5 or 10J wide wheels. My issue is that someone supposedly very reputable is regularly fitting 275 20 tyres to 8.5J wheels. As best I can tell that is not recommended and verging on unsafe.

 

[BognorMotors]

The ongoing tyre saga.....275/40 is oversize, 265/40 is the better size, and the 275/40 is still sold by many resellers, due to the cheaper availability of it and being an ex Range Rover size

Let us not forget however that 275(35) works perfectly on a 9” width, which shows how fine the tolerances are. It is an approved size, and is also the VW approved size. They haven’t a T32 approved size which makes life even harder, when choosing tyres.

We actually had a customer insist on a 275/40 on a 10” rear(we recommended 265/40), with 265/40 on a 9” front(which we recommend and agreed with). He was T32 for reference. Fully lowered on B14Komforts and the rear rubbed over big bumps, on the OS only. First van we’ve ever seen where the rear have rubbed - there is so much room in the rear arch. He does carry weight so was low, and ride is still 100% we Heat gunned the inner arch to sort it though. Not ideal mind!

Another complication to consider is 4Motion- we see probably as many 4Motions as 2wd and the tyres need to match front and rear. So you can run staggered wheels, but with the same tyres all round, or you will play havoc with the 4wd system.

All part of the fun of it.


I was actually having a conversation about this very subject with one of the more sensible, and biggest alloy wheels resellers the other day. I wonder when the present recommendations were made for tyre width and wheel width - not something I know- but tyre technology has come so far in recent times

 

[Tsixty]

The ongoing tyre saga.....275/40 is oversize, 265/40 is the better size, and the 275/40 is still sold by many resellers, due to the cheaper availability of it and being an ex Range Rover size

Let us not forget however that 275(35) works perfectly on a 9” width, which shows how fine the tolerances are. It is an approved size, and is also the VW approved size. They haven’t a T32 approved size which makes life even harder, when choosing tyres.

We actually had a customer insist on a 275/40 on a 10” rear(we recommended 265/40), with 265/40 on a 9” front(which we recommend and agreed with). He was T32 for reference. Fully lowered on B14Komforts and the rear rubbed over big bumps, on the OS only. First van we’ve ever seen where the rear have rubbed - there is so much room in the rear arch. He does carry weight so was low, and ride is still 100% we Heat gunned the inner arch to sort it though. Not ideal mind!

Another complication to consider is 4Motion- we see probably as many 4Motions as 2wd and the tyres need to match front and rear. So you can run staggered wheels, but with the same tyres all round, or you will play havoc with the 4wd system.

All part of the fun of it.


I was actually having a conversation about this very subject with one of the more sensible, and biggest alloy wheels resellers the other day. I wonder when the present recommendations were made for tyre width and wheel width - not something I know- but tyre technology has come so far in recent times

But the thread really isn't about 275 vs 265, which is well discussed already. It is about putting a 275 tyre on an 8.5j wheel which you don't mention.......
Oh and don't forget the 265s are oversize as well, just a tiny bit less oversized than the 275s.
Tyres do not need to match on a 4Mo, the overall circumference of whatever is fitted to the front and rear needs to match. That is where the root of my issue is, the van has staggered wheels but because it is a 4Mo the inept supplier has put the same tyres on the front as the back in the naive belief that they have to because it is a 4Mo. What they should have done is found the closest circumference tyres suitable for the 8.5j front wheels to the 275 40 that were fitted to the wider rear wheel. But then I suppose their only interest is selling expensive vans, not what customers have to deal with afterwards.

 

[BognorMotors]

Yeah I went a little off topic, but of course I fully understand the thread - I’ve picked up on the 275/40 tyre issue. Which shouldnt be fitted to any transporter IMHO. Which also means it should never be on an 8.5” ! Surely I don’t need to mention this, it’s obvious, maybe not. A 265/40 is better, but still not ideal but we are restricted by tyre sizes available, so you would be better matching that size if possible on the front.

However expanding on what I’ve written is I’m talking about how tight the tolerances are in tyres. 275 is accepted (and approved by VW - which actually confuses it more)for a 9” whereas, but not for 8.5”. So I’ll go into more detail, a 265 is also considered too wide for an 8.5, whereas the 255 is considered the widest, which means with half an inch of rim width decrease (12.7mm) the acceptable tyre goes down 20mm, so many different parameters effect this.

On a 4Motion t32 for instance, we choose to run 265 all round, you really have no option, especially if you want to go staggered. Ideally you’d want to go 9/10 to get it fitting perfectly. But this isn’t always catered for. It’s a minefield for sure. And for any warranty issues same tyres is the first thing VW look at in a warranty claim so be very careful. I’m at VW again next week so will ask the question on tolerances, and see if anything has changed. I suspect not.

We are constantly, as a business looking at tyre sizes and available tyres, and the manufacturers seem to be listening more and more to demand.

Now going OT again, although maybe not as this is why a 275/40 is increasingly used more, but Throwing the 275/35 back into the mix this used to be available a few years back for T32, as a Bentley fitment tyre. The manufacturers realised we were all using these 103 tyres for vans, then changed the print on it with no weight rating, but the kg printed in small letters. Then dropped it all together. The alloy wheels manufacturers, and inparticular, Supermetal begged for other tyre manufacturers to make this size. But no one stepped up. Maybe one day this size will come back and make life a bit simpler, for over 9” runs at least, and T32. This doesn’t help the 8.5 front....

Anyway let the debate continue, and sorry for the diversion, but the VW transporter and lack of correct tyres, has been an issue for many years so I’m off to bed.

 

[Andysmee]

I don't understand why people stagger the wheel size? I can't think of an OE that does it, apart from some rear wheel drive monsters. Surely it's even more pointless if you put the same tyre width on, as you don't even get the looks? And on 4Motion, you don't need the grip (and you won't get from the narrower tyre matching the front). If it's just for arch fit, then a small spacer is sufficient.

 

[Tsixty]

@BognorMotors thanks for your input and just to be clear to everyone else I wasn't referring to yourselves in my comments pointed towards the company that originally supplied the van I'm driving.

On a 4Motion t32 for instance, we choose to run 265 all round, you really have no option, especially if you want to go staggered.

I now know that I have no choice but to be staggered or buy new wheels (on the assumption that when I take a rear wheel off it will be either a 9 or 9.5 which I'm sure it will be. What is your view on 245/45 on 8.5J on the front and 275/40 on 9/9.5J on the rear on a 4Mo given that there is less than 1mm difference in the overall diameter of the wheel/tyre combination and given that I'm unlikely to have much choice? I'm likely to give it a go as I don't see that I have much choice other than to buy new wheels. Do you have any other suggestions given that a 265 isn't really going to be suitable on an 8.5J rim so 265s all the way round isn't doable for me either (and the tyres I want aren't available in 265/40 although that ultimately wouldn't be the single deciding factor)?

 

[BognorMotors]

I don't understand why people stagger the wheel size? I can't think of an OE that does it, apart from some rear wheel drive monsters. Surely it's even more pointless if you put the same tyre width on, as you don't even get the looks? And on 4Motion, you don't need the grip (and you won't get from the narrower tyre matching the front). If it's just for arch fit, then a small spacer is sufficient.

Its aesthetics - Well it is for me, and most/all of my customers. We tend to set them up the same width tyre all round. We get tyres and rim widths that work with both sizes. 4Motions as stated above have to have the same rolling radius or it plays the transfer box up.

This is why the transporter is so unique, everyone can put their personal stamp on it. What one person likes another doesn't.

@BognorMotors thanks for your input and just to be clear to everyone else I wasn't referring to yourselves in my comments pointed towards the company that originally supplied the van I'm driving.



I now know that I have no choice but to be staggered or buy new wheels (on the assumption that when I take a rear wheel off it will be either a 9 or 9.5 which I'm sure it will be. What is your view on 245/45 on 8.5J on the front and 275/40 on 9/9.5J on the rear on a 4Mo given that there is less than 1mm difference in the overall diameter of the wheel/tyre combination and given that I'm unlikely to have much choice? I'm likely to give it a go as I don't see that I have much choice other than to buy new wheels. Do you have any other suggestions given that a 265 isn't really going to be suitable on an 8.5J rim so 265s all the way round isn't doable for me either (and the tyres I want aren't available in 265/40 although that ultimately wouldn't be the single deciding factor)?

Thanks, @Tsixty . I know you were not talking about us

I've actually put some calls in this morning to our local dealer on 4motion, and a very large tyre wholesales to get the official line on what tyres work on what rim, as its a lot more in-depth than just the width, profiles come into account too.

Still, at least it's given me something to get my teeth into today

As soon as I hear anything I'll get back to you

 

[Tsixty]

@BognorMotors thanks for you help.

 

[huw169]

@BognorMotors thanks for your input and just to be clear to everyone else I wasn't referring to yourselves in my comments pointed towards the company that originally supplied the van I'm driving.



I now know that I have no choice but to be staggered or buy new wheels (on the assumption that when I take a rear wheel off it will be either a 9 or 9.5 which I'm sure it will be. What is your view on 245/45 on 8.5J on the front and 275/40 on 9/9.5J on the rear on a 4Mo given that there is less than 1mm difference in the overall diameter of the wheel/tyre combination and given that I'm unlikely to have much choice? I'm likely to give it a go as I don't see that I have much choice other than to buy new wheels. Do you have any other suggestions given that a 265 isn't really going to be suitable on an 8.5J rim so 265s all the way round isn't doable for me either (and the tyres I want aren't available in 265/40 although that ultimately wouldn't be the single deciding factor)?

You’ll get greater than 1mm variation in manufacturing tolerances of the same tyre, and don’t forget the tread depth that is a wear point. Over half an inch on diameter. Then you’ve got the pressure difference.
I think you might be over analysing this a tad.

 

[Tsixty]

And the answer is..................8.5J on the rear as well so I was wrong. Not staggered wheels, just wheels that are too narrow for the tyres on them . I'm not sure which way to turn now. 245/45/20 all the way round or 265/40/20 knowing that the tyres are still too wide for the wheel but are 10mm better than the 275s on there currently?

 

[T6ARF]

And the answer is..................8.5J on the rear as well so I was wrong. Not staggered wheels, just wheels that are too narrow for the tyres on them . I'm not sure which way to turn now. 245/45/20 all the way round or 265/40/20 knowing that the tyres are still too wide for the wheel but are 10mm better than the 275s on there currently?

Are your front tyres worn out, or are you just looking to replace them because of the oversize?

 

[Tsixty]

Are your front tyres worn out, or are you just looking to replace them because of the oversize?

Initially because they are cheap nasty tyres, I put up with them for a few months while the weather was reasonable but now the winter is approaching I want to change them (all 4) to all seasons. But then, while researching discovered that the wheels are 8.5 and the tyres are 275/40. Everything I read says that a 275mm wide tyre is way to wide for an 8.5" wide wheel and I really don't want to buy new wheels.

 

[T6ARF]

Initially because they are cheap nasty tyres, I put up with them for a few months while the weather was reasonable but now the winter is approaching I want to change them (all 4) to all seasons. But then, while researching discovered that the wheels are 8.5 and the tyres are 275/40. Everything I read says that a 275mm wide tyre is way to wide for an 8.5" wide wheel and I really don't want to buy new wheels.

Ok, in that case I think to get the load rating you need, you’ll have to go with the 245/45/20 all round.... black circles have got an offer on at the minute on Michelin Cross Climate SUV?

 

[Tsixty]

Ok, in that case I think to get the load rating you need, you’ll have to go with the 245/45/20 all round.... black circles have got an offer on at the minute on Michelin Cross Climate SUV?

Yup,and the tyres I want (Vredstein Quatrac Pro) are available in that size at 103 load rating and £171 each. Looks like I'm going down the 245/45/20 route then.