Understanding and choosing tires

Post Reply
eshvos
Posts: 83
Joined: 09 Sep 2019 12:40

Understanding and choosing tires

#1 Post by eshvos » 19 Jun 2021 08:00

Hi everyone!

Yesterday I made a big mistake and decided to dive into the world of (truck) tires. I have always avoided this topic, as I knew there would be endless combinations possible.

As far as I understand it:
Traditionally European trucks and trailers used to run the following configuration (or something similar):
  • steer: 315/70R22.5
  • drive: 2 × 315/70R22.5
  • drive: 2 × 315/70R22.5
  • trailer: 2 × 315/70R22.5
  • trailer: 2 × 315/70R22.5
There are still trucks and trailers around with this configuration (I've looked at trailer sales and surprisingly I have still found a couple of new trailers with dual tires), but they are getting rarer and rarer (unlike Canada/USA, where this is still the standard configuration; In North America they usually also use tires with a height of about 40": e. g. 295/75R22.5 or 445/50R22.5 supersingles)

In the late 70s and 80s things in Europe began to change, as tire technology advanced and axle laws changed. Nowadays the most popular configuration seems to be:
  • steer: 385/55R22.5 or 385/65R22.5 (the latter seems more common on new trucks)
  • drive: 2 × 315/70R22.5 (alternatively 495/45R22.5 supersingle)
  • trailer: 385/65R22.5
  • trailer: 385/65R22.5
  • trailer: 385/65R22.5
Now this is where I no longer understand the choice of tires in Europe:
  • Why do they use larger tires on the trailer (385/65) than on the truck (385/55)? If they use 385/65 on the steer axle of the truck, why do they put tires with different heights on the truck (steer vs drive axle)?
  • I guess they need the 315/70R22.5 tires for a lower fifth wheel height, but why don't they use 385/55R22.5 tires on steer and trailer axle instead?
  • If they use the smaller 385/55 tires: Why do they use 385/55R22.5 on the steer axle, if the goal is to swap them on a trailer axle when they are worn? How can they put a smaller tire (385/55) on the trailer that's running the larger tires (385/65)?
  • Wouldn't it make more sense to either use 385/65R22.5 on the steers and 2 × 315/80R22.5 (or ~445/60R22.5 supersingles; this size doesn't exist on the Michelin website for Europe) on the drives or use the smaller 385/55R22.5 tires on the trailer?
Can someone please explain the reasoning behind the choice of tires on modern European trucks?

In North America a modern supersingle configuration looks like the following, which is much more logical to me, as tire heights are about the same and this makes the supersingles a drop-in replacement and interchangeable with dual tires:
  • steer: 295/75R22.5
  • drive: 445/50R22.5
  • drive: 445/50R22.5
  • trailer: 445/50R22.5
  • trailer: 445/50R22.5


This brings me to the game: I already realized that tire sizes in ATS are pretty unrealistic, as ATS uses an almost nonexistent tire size. But ETS uses 385/65R22.5 on the trailer and 315/70R22.5 on the drives and steers, which is, apart from the steer axle, quite realistic.
What tire configuration do you run? Which do you prefer? How do I choose the correct tire sizes?

With my current knowledge I would prefer to run as many interchangeable tires as possible. I have tried putting dual tires on my trailer and it greatly improved stability (feels more like an American trailer now), but as this is increasingly unrealistic, expensive and heavy, I am thinking about putting 385s on the steer axle and the trailer, but I can't really decide if 385/55R22.5 or 385/65R22.5 would be the more economic and more realistic choice for the steers and trailer tires.
I am also not sure if I should put supersingles on my drive axle(s) for weight savings (not sure about disadvantages in traction).
Maybe it would even be better to not run universal tires ("Z" for Michelin) and instead choose the ideal tire for each axle and not worry about interchangeability, but this does also seem unrealistic, as in real-life steer tires seem to be swapped on the (middle) trailer axle quite often.

I wish I would not have started to think about tires ... I can't stop thinking about them now ... :roll:

As you can see, I am very confused now and would love to see a discussion about tire sizes and configurations in-game and in real-life.
Goodbye. No interest in participating in a community where posts get silently deleted without any explanation.
Truckdrivr
Posts: 217
Joined: 07 Feb 2021 10:04

Re: Understanding and choosing tires

#2 Post by Truckdrivr » 19 Jun 2021 13:39

eshvos wrote: 19 Jun 2021 08:00 if the goal is to swap them on a trailer axle when they are worn?
i think your (nice) theories is broken by this one sentence.i dont think its the goal at all, now i dont know how its done in every country of Europe but for all i know swapping tires to be used on trailer once they are worn i have not heard about, if a tire is worn on out it has no grip, you wouldnt put a worn down tire on your trailer it has to have grip too. The only way i can think of a reuse if the the tire gets new threads mounted (dont know the english term) but that wouldn't be on steering wheels either as its not legal to use tires with replaceable threads on steerable axels.
Last edited by Truckdrivr on 19 Jun 2021 13:42, edited 1 time in total.
Convoy nametag: Truckdrivr
See you on the road 8-)

My screenshot thread: viewtopic.php?f=47&t=302557
User avatar
xXCARL1992Xx
Posts: 16527
Joined: 17 Aug 2016 12:18
Contact:

Re: Understanding and choosing tires

#3 Post by xXCARL1992Xx » 19 Jun 2021 13:41

if the tire is worn down to max you throw it out, no question asked, or you send them back to whoever manufacturer for retreading if possible
| !!!NO SUPPORT OR REQUESTS OF ANY SORT VIA PM!!! | Screenshot Thread | Steam Workshop | World of Trucks Profil |
[ external image ]
eshvos
Posts: 83
Joined: 09 Sep 2019 12:40

Re: Understanding and choosing tires

#4 Post by eshvos » 19 Jun 2021 15:01

@Truckdrivr As far as I know, you regroove the steer tires according to manufacturer specification once they are worn the first time. Afterwards you put them on the steer axle again (if allowed in the respective country) or on the trailer. After the regrooved tires have worn the second time, you retread them and put them on the trailer (or sell them). Once they are worn the third time, they can't be restored another time and you have to buy a set of new tires.

Please correct me if I'm wrong.
Goodbye. No interest in participating in a community where posts get silently deleted without any explanation.
Truckdrivr
Posts: 217
Joined: 07 Feb 2021 10:04

Re: Understanding and choosing tires

#5 Post by Truckdrivr » 19 Jun 2021 18:55

from a cost benefit point of view i think that getting the tires rethreaded is not worth the time and money over buying a new tire (again dont know every country) and be on the road instantly again, i imagine rethreading takes quite the time. Regrooving on the other hand i believe is more common, and on my own truck i have infact regroovables on steer and drive axel, although my tires dont get regrooved but gets replaced by new ones every time i have worn down my old ones.
Convoy nametag: Truckdrivr
See you on the road 8-)

My screenshot thread: viewtopic.php?f=47&t=302557
eshvos
Posts: 83
Joined: 09 Sep 2019 12:40

Re: Understanding and choosing tires

#6 Post by eshvos » 19 Jun 2021 19:34

What do you think about the following ETS setup?
  • steer: 315/70R22.5
  • drive: 2 × 315/70R22.5
  • (drive: 2 × 315/70R22.5)
  • trailer: 385/55R22.5
  • trailer: 385/55R22.5
  • trailer: 385/55R22.5
This would have the benefits of lower tare weight for the trailer, more reliable traction on the drive axles (aquaplaning, etc.), lighter steering and only two tire sizes (it would theoretically possible to carry one spare wheel on the truck and one on the trailer, if a country mandates one). Rotation between truck tires on each vehicle would be possible.
Supersingle weight savings on the drive axle can't be utilized though, but I guess it might actually be better to have a slightly heavier tractor and not cheap out on additional safety (or lower repair costs if one drive tire runs flat or blows).

After researching for sale ads, I noticed that nearly no-one uses supersingles on the drive axle(s) in Europe. Therefore I guess that it would be more realistic to use dual tires on the drive axle(s). For the steer axle it seems to be a tie. Some mount 315/70 (e. g. new Daimler trucks), others use 385/55 or 385/65 for a higher front axle capacity or interchangeability with the trailer.
The reason for using the non-height-matching 385/65 tires instead of 385/55 seems to be the higher load index (164 vs 160). 164 or greater allows for a 10 t axle weight, 160 only allows 9 metric tons per axle. I have only found a single 385/55 tire with a load index of 164 ("Giti GSW226"). Maybe in the future with advancements in tire technology, it will be possible to use 385/55 tires from different manufacturers on trailers without sacrificing axle weights. Maybe I will use 385/65R22.5 tires on the trailer until the smaller tires become available with a higher load index for trailers in real-life (if ever). The height difference doesn't really matter anyways, if you don't plan on using the 385/65 tires on the steering axle.
EDIT: Krone (Hämmerling is the tire manufacturer for Krone) has 385/55R22.5 tires with a load index of 164. They are also available for non-Krone trailers under the ATHOS 5 brand. The Krone press release is available in English in the downloadable zip. For the ATHOS website one has to use a translation service. So using 385/55 is actually realistic, even though it is still a rare occurence ...

For ATS I would decide on a similar setup:
  • steer: 295/75R22.5
  • drive: 2 × 295/75R22.5
  • drive: 2 × 295/75R22.5
  • trailer: 445/50R22.5
  • trailer: 445/50R22.5
  • (trailer: 445/50R22.5)
These tire configurations would also be viable for owner-operators that don't own trailers, as they wouldn't be able to rotate 385/65R22.5 tires from the steering axle to a trailer axle and using 385/65R22.5 on the drive axle is extremely rare (especially in America), even though I have read about one operator running them on a Scania truck. I haven't looked into the disadvantages of these tires on a drive axle though, as this is so rare that I decided it is not worth my time. 8-)
Goodbye. No interest in participating in a community where posts get silently deleted without any explanation.
scaniadriver01
Posts: 320
Joined: 18 Apr 2020 22:34

Re: Understanding and choosing tires

#7 Post by scaniadriver01 » 19 Jun 2021 22:12

1st only international truckdrivers have sparewheels with them..
i drive locally and my boss removed the sparewheels from the truck and trailer to carry more cargoweight
if i have a blowout im always nearby a tireshop so they will come to me with a van to replace the tire...
they say its cheaper to pay 1 time for a tire-van then to carry 3 sparewheels all the time wgile that 250 to 300 kg can be worth money to carry more cargo

2nd.. truck tires dont fit trailers..
its a different tread, different tire and different rim.. doesnt fit the hubs..
if a truck has a sparewheel it will have a tire on it for the front axle.. never the rear as you will get tracking/steering issues because its a different tread..

also some trucks have a smaller ( 75cm diameter) wheel for thier midlift.. some companies use that if they dont need a fullsize midlift all the time and with a sideskirt you can hide that small wheel behind it..so the truck looks like a 4x2 but is a 6x2

different size tires are demanded for different types of use.. thinner tires are good for when you need to turn a lot.. as they cost way less then a supersized tire.. wider tires are commenly found in my experience and what i see during work on volume trailers.. big boxtrailers with small wide wheels.. as they cruise nicely at long distance driving.. are also more stable..
User avatar
xXCARL1992Xx
Posts: 16527
Joined: 17 Aug 2016 12:18
Contact:

Re: Understanding and choosing tires

#8 Post by xXCARL1992Xx » 19 Jun 2021 22:48

All purpose tires do exist that can be used on truck and trailer (Michelin X Line Energy Z or Michelin Multiway HD XZE) made for steer, drive and trailer
| !!!NO SUPPORT OR REQUESTS OF ANY SORT VIA PM!!! | Screenshot Thread | Steam Workshop | World of Trucks Profil |
[ external image ]
scaniadriver01
Posts: 320
Joined: 18 Apr 2020 22:34

Re: Understanding and choosing tires

#9 Post by scaniadriver01 » 19 Jun 2021 23:14

xXCARL1992Xx wrote: 19 Jun 2021 22:48 All purpose tires do exist that can be used on truck and trailer (Michelin X Line Energy Z or Michelin Multiway HD XZE) made for steer, drive and trailer
not being used much then..
as scania comes on michelins from the factory
but usually the fronttires are rounded and the rears are flat as they dont steer..

i havent seen all purpose tires.. yet
wide tires here are usually used for show as with the narrow streets i usually need to go to its not worth it and would destroy tires by clipping curbs that usually happens with my job..
Post Reply

Return to “General discussion about the game”

Who is online

Users browsing this forum: No registered users and 6 guests