Hi all, just wanna find out whether its ok to fit four wheels with the same size. my current ride is front and rear are of diff sizes. TQ!

if rims size identical...can... if very different then cannot

need rim info tbh

both identical at 18'.

need the rim width...

example ori BMW front can be 8" wide...rear 9"... here you cannot use 4 identical tyre size

tell us the front/rear tyre spec we should be able to deduce

Need more info. What car and what are the sizes for the front and rear. Might have a staggered setup from the factory.

W205 c250.

anyone has review on proxes TR1? good or bad?

Good dry and wet grip. Great for some spirited driving

Called up Mercedes Benz malaysia, cant have four at the same size coz the rear rims are wider than the front!
Thanks for the heads up! Looking at this tyre. Was a supporter of TIR when i had my Accord!

Nonsense! My rims are 18x8 front and 18x9 rear and I just use same 245/40/18 on all 4! Tire size also got range if fitment possible so like 245 can fit for 8-9.5jj width.

TR1 btw some say ok but I have also heard bad comments on it saying the grip is not good, so not sure.

front looks more pregnant wor... hahaha

Not really, it looks more square while the rear will look more rounded. Anyway it still works perfectly fine, no issues whatsoever, so people who say must use staggered tire sizes are incorrect. Basically for my 8jj at the front, I can run 225/235/245 while my 9jj at the rear can run 235/245/255/265 so there are 2 sizes overlapped which can be used for all. Of course running staggered sizes vs all same will give some different handling behaviour. Smaller fronts will make more understeer while all same will be more neutral handling or sharper front end bite.

yeah... tbh for this profile... 10mm difference from 225 vs 245 not that noticeable... but a lot depends on the sidewall too... 235 probably a good compromise

btw cant generalized smaller front = understeer... got many factors involved... also understeer is preferred and safer for 99.9% of people... imho all the cars are designed slightly understeer anyways...

edit: do you rotate your 9jj to the front?

This post has been edited by dwRK: Sep 11 2020, 09:27 AM

I was talking in relativity, so smaller fronts will be relatively more understeer than all same sizes. I have tried both tire setups on my staggered rims.

No, I never rotate them, will look ugly and might not fit that width to the front also. I am actually looking to change back to all same sizes rims now so I can rotate.

LOL.....they are the "expert" mah! They told me will affect the sensor ler. Not sure how true la.

So bro, if 245 change to 235 then the diff is bearable ? Pricing wise also diff a lot ler. lol.

buy a pump...don't use run flats... then everything becomes cheap...

hahha....mine are non RFT ler.

yes I know...

btw we never chat before but just wanna say thanks for your feedback throughout the years...

What sensors?? Often they just talk only coz they don't know how to explain and just take the easy way out.

As he mentioned above if change width also need to consider the sidewall height because 245/40 is taller than 235/40 but less than 235/45. What are your actual sizes now? (Sorry if already mentioned before, I might not notice it).

This post has been edited by 6UE5T: Sep 11 2020, 11:45 AM

No probs, glad to be of any help.

Front 225/40/18 and rear is 245/45/18.

weird profile combo tbh... you bought used car?

maybe you mean 225/45 + 245/40?... 235...40 or 45 should not be a problem... BUT really you should check your rim size like I said... I dunno what is fitted and dunno any overlap... so don't want to give wrong advice

This post has been edited by dwRK: Sep 11 2020, 12:39 PM

Ya very unbalanced combo. The front is way too small in rolling diameter, very thin profile, while the rear is very tall sidewall! Difference in sidewall height is a massive 2cm! Your car must be low at nose while the rear sticking up, and the fender gaps at the front is much bigger too. Stock Merc C class should not be like that. Are you sure they're not 225/45/18 and 245/40/18??

let me check...... . Mine is local stock car ler. i dont buy recond one. I could be wrong on the sidewall 's measurement.

anyways... 235*4 is probably about same cost as 225*2 + 245*2

don't think you gonna save much... just give you some flexibility in terms of rotation if uneven wear

Yeah guys.... sorry that i got it wrong ! it should be the other way round. Yeah.....its more about able to rotate the tyres rather than cost.

Ah ok, my staggered sizes also last time were the same. Then I'd suggest you use 245/40/18 all around for better traction and slightly sharper front end turn in. But in order to rotate you'd still need to dismantle the tires from the rims to switch them because your rims are staggered sizes, so still not as convenient.

You may always find the recommended tyre size on the driver's seat side door. There have a sticker beside the door of your driver seat, just refers to there.

You also may refers to this website https://tiresize.com/tyre-size-calculator/ and find your tyre size, as long as not more than 3% is acceptable.

Why u not follow stock car tyre profile?. and believe strangers people on internet instead. some model indeed they design like that lo. Must be got a reason why they design like that lo. if u belip random people everywhere means u belip them more compare to mercedes engineer.

Maybe if different size rotate to left right only instead of cross it to front like ordinary cars.

Chill dude. Suddenly so harsh. lol. although somehow agree its always the best to follow factory fitted setting.

Another thing to check is what are your exact rims width? If the front is only 7.5jj then you can only fit 225 tires and cannot fit 245. You need minimum 8jj width to fit 245.

I don't know C class rims width. If BMW F30 328i/330 MSport, they also come with staggered rims size 18x8jj/8.5jj with stock fitment 225/45/18 and 255/40/18. The non sport model comes with all same 18x8jj rims with 225/45/18 only.

Some people just swallow just whatever SC tell them even without proper proof or explanation, easy meat to get con by workshops.

Lel. never know sc the one who determine car tyre size, not car engineer. kek.

I suspect front is 7.5...rear 8.5... asked ts to check full rim info many times d...

anyways ts wanna avoid 245 because of cost... so for 7.5/8.5, I think only 225 and 235

my big issues are offsets and clearances...so even if can fit 4 identical, might not be able to rotate back to front...and even if no rubbing, every time rotate handling will change

Standardising tyre width size to 225 or 235 is fine with 7.5/8.5 J .
TS really wanna to confirm actual rim size is in compliance with 7.5 - 8.5 J .

- delete -
Double post .

This post has been edited by zeng: Sep 11 2020, 09:29 PM

strangers have no vested interest... ts' job is to determine if our feedback makes sense and can be trusted

CS has vested interest to protect company's reputation...so it's almost always follow ori parts...

few years back I got into big arguments with a lyn idiot who says oem not good must go back to ori... and if I go oem means I not rich enough to drive BMW... lol

Pretty same old grandma story. Even if someone could afford the car, maintenance and what not. Do they have to accept whatever cost blindly? Lol

Thanks all bro for the feedbacks! Appreciate!

Im not argue which tyre is good which tyre is not or original tyre must use back or oem parts whats not..

Im just advice ts to stick to original specs, as he not even change rims. I believe original specs is the best. And there is a reason engineer made rear wheel bigger compare to front.

I believe some u had had hear 'If it ain't broke don't fix it'.

Yeah I also suspect as such, so max can only go 235/45 but will be about 0.5cm taller sidewall, will be slightly heavier but more comfortable. Handling might be slightly more neutral but not much noticeable if just normal driving.

hate to burst your bubble... the design / look of the car, including wheels, are not done by automotive engineers... if you investigate US/UK/Japan/etc spec, you will also find it can fit a range of wheel sizes depending on marketing needs... practically all cars can and have identical 4 wheels...while the more expensive variants are staggered... because it looks sporty, progressive, and fetches a premium.

I agree that the original sizes fitted are optimal for the rim, but within the rim spec, you have an upper and lower limit that you can also fit other sizes. changing from staggered to 4 identical doesn't make the car suddenly bad or suboptimal... the sizes we suggested are after all within the engineering limits...

so bro, from 245 to 235 is not a big issue right? E.g from 245/40/18 to 235/40/18. Think TR1 doesnt come in 245.

235/40 is 0.5cm thinner profile than 245/40 and 0.8cm thinner than 225/45 so you will feel noticeably harsher ride/less comfortable. Will look uglier as well coz fender gaps increased by as much. I personally wouldn't use that.

Your front rim is probably of 7.5J size which doesn't quite permit 245 width tyres .
Hence factory original tyre width is 225 mm , where one may 'upgrade' to a 235 mm width tyres for rationalisation .
Your rear rim can accomodate narrower 235 mm width (instead of original 245 mm) and it is fine to 'modify' so , although it may be at an imperceptible slight expense of lower capacity of power/torque transfer aka pick-up power if that doesn't matter to you .

This post has been edited by zeng: Sep 12 2020, 12:57 PM