The equivalence between
old and new agricultural tyre markings

Are you looking to replace an old set of tyres or change a trailer tyre, but you don't quite understand all the numbers and letters you see printed on these tyres?

Tractor tyre markingYou will have noticed by now that there are a number of different markings on your tractor tyres: a dimensions marking that is common to all recent tyres, along with other markings that can be trickier to understand. In this article, we provide you with a helpful table to navigate these different codes so you can make sure you're choosing the right size tyre.

 

Markings are governed by a european standard to simplify and standardise tractor tyre dimensions

The ETRTO (European Tyre and Rim Technical Organisation) introduced the ISO 5775 standard to help clarify tyre dimensions, which used to be somewhat vague: sometimes in inches, sometimes in millimetres, and very often varying from one manufacturer to another.

The new ETRTO standard has brought a certain degree of standardisation to tractor tyre markings. However, it's entirely possible that your tyres are a little older, from an unknown brand, or are trailer tyres that do not yet meet this standard.

You therefore need to understand all of these other markings to be sure that you're buying the equivalent in the right size under the new standard.

Older tractor tyre markings are often given in inches, using the following format:

Marquage pneu de tracteur en poucesHere's what you need to know to understand the dimensions markings for older tyre models.

You will see a code that more or less matches what is shown in the photo opposite:

13.6 R 28
or 16.9 R 30
or 12.4 R 28
or 8.3 R 24
etc...
Always in the same format:
Number with one decimal point – Letter or dash – Number.

The first number is the width of the tyre in inches, so the tyre in the photo is 13.6 inches wide (flange width = the distance between the outside of the sidewalls in an inflated tyre).

The letter R stands for radial, a type of internal tyre structure (a dash instead of an R refers to a bias tyre).

The final number, 28 in the photo, is the rim diameter in inches (1 inch = 25.4 mm).

 

The european ETRTO tyre marking system provides greater clarity

ETRTO tractor tyre markingIf you're looking to replace your tyres, here's everything you need to know about the new European tyre marking.

It is made up of a series of letters and numbers in the following format:

600/65 R 28
or 460/85 R 38
or 750/55 R 26
etc...

The format is always the same:
Number slash number – Letter – Number

The first number is the tyre width in millimetres, so the tyre in the photo is 600 mm wide (flange width = the distance between the outside of the sidewalls in an inflated tyre).

The second number is the sidewall height expressed as a percentage of the width, so the '65' in the photo means 65% of 600 mm = 390 mm sidewall height (this figure corresponds to series, such as 50 series, 60 series, 65 series, 80 series etc. The higher this number, the higher the sidewall).

The letter R stands for radial, an internal tyre structure.

The final number, 28 in the photo, is the rim diameter in inches (1 inch = 25.4 mm).

Here is the dimension equivalence table for old markings in inches (or trailer tyre markings) and the new marking standards for agricultural tyres

This table shows the equivalents for new and old markings, as well as the different tyre width options for the same rim (narrow wheels or wide tyres, depending on the type of work they're needed for).

95 - 90 - 85 - 80 series
ETRTO RADIUS RIM ∅ TYRE DIMENSION
Non millim. 95 series 90 series 85 series 80 series
350 16 6,00-16         210/80R16
390 16 7,50-16         250/80R16
410 18 7,50-18         250/80R18
450 20 9,5-20         260/80R20
475 20 11,2-20       280/85R20  
500 20 12,4-20       320/85R20 340/80R20
500 24 9,5-24     240/85R24 250/85R24  
525 24 11,2-24     280/85R24    
550 24 12,4-24     320/85R24    
550 28 9,5-28     240/85R28 250/85R28  
575 24 13,6-24 340/85R24        
575 28 11,2-28 280/85R28     320/70R28  
575 32 8,3-32 210/95R32        
600 24 14,9-24 380/85R24     420/70R24 460/70R24
600 28 12,4-28     320/85R28    
600 32 9,5-32 230/95R32        
625 24 16,9-24 420/85R24        
625 28 13,6-28     340/85R28    
625 32   270/95R32        
625 36 8,3-36 210/95R36        
650 28 14,9-28 230/95R32     380/85R28  
650 32 12.4-32     320/85R32    
650 36 9,5-36 230/95R36       270/80R36
650 40 7,2-40 180/95R40        
675 28 16,9-28     420/85R28    
675 30 14,9-30     380/85R30    
675 32     320/90R32      
675 34       320/85R34    
675 36 11,2-36 270/95R36        
675 38 9,5-38 230/95R38        
700 30 16,9-30     420/85R30    
700 36 12,4-36     320/85R36    
700 38 11,2-38 210/95R36 270/95R38 290/90R38    
700 40   230/95R40        
750 26 23,1-26 28L26        
750 34 16,9-34     420/85R34    
750 38 13,6-38 15,5-38   340/85R38    
750 42 11,2-42 270/95R42        
750 44 9,5-44 230/95R44        
775 34 18,4-34     460/85R34    
775 38 14,9-38     380/85R38    
775 42 12,4-42 230/95R44 300/95R42      
775 44   270/95R44        
800 30 23,1-30 230/95R44        
800 38 16,9-38     420/85R38    
800 42     320/90R42      
800 46     270/90R46      
800 48 9,5-48 230/95R48        
825 34 20,8-34 23,1-34        
825 38 18,4-38     460/85R38    
825 46 12,4-46 270/95R46 300/95R46 320/90R46      
825 48   270/95R48        
825 50       270/85R50    
875 32 30,5LR32          
875 38 20,8-38     520/85R38    
875 42 18,4-42     460/85R42   480/80R42
875 46     380/90R46     420/80R46
875 48 13,6-48     340/85R48    
875 50   300/95R50 300/90R50 320/90R50      
925 32       680/85R32    
925 42 20,8-42     520/85R42    
925 46 18,4-46     460/85R46    
925 52   300/95R52        
925 54   270/95R54 320/90R54      
975 38       650/85R38    
975 46 20,8-46     520/85R46    
975 50           480/80R50
1025 38     710/85R38      
75 - 70 - 65 series
ETRTO RADIUS RIM ∅ TYRE DIMENSION
Non millim. 75 series 70 series 65 series
330 16     200/70R16      
340 16         240/65R16  
350 16 6,00-16   240/70R16   260/65R16  
360 16 6,50-16   260/70R16   280/65R16  
390 16 7,50-16   280/70R16   300/65R16 320/65R16
390 18     260/70R18      
400 16     300/70R16      
410 18 7,50-18   280/70R18   300/65R18 320/65R18
410 20     260/70R20      
425 18 10,5/80-18   300/70R18   340/65R18  
425 20 7,50-20   280/70R20      
450 20 9,5-20   300/70R20   340/65R20  
475 20 11,2-20   320/70R20      
500 20 12,4-20 340/75R20 360/70R20   420/65R20  
500 24 9,5-24   300/70R24      
525 20 13,6-20 380/75R20 380/70R20   440/65R20  
525 24 11,2-24   320/70R24      
550 24 12,4-24   360/70R24   420/65R24  
550 28 9,5-28       340/65R28  
575 24 13,6-24   380/70R24 400/70R24 440/65R24  
600 24 14,9-24     480/65R24    
600 26.5            
600 28 12,4-28   360/70R28     420/65R28
600 32 9,5-32 270/75R32        
625 24 16,9-24   480/70R24   540/65R24  
625 26.5            
625 28 13,6-28   380/70R28   440/65R28  
650 26 16,9-26   480/70R26   540/65R26  
650 28 14,9-28 420/75R28  420/70R28   480/65R28  
675 26 18,4-26   520/70R26 580/70R26    
675 28 16,9-28   480/70R28   540/65R28  
675 30 14,9-30   420/70R30      
675 30.5            
700 26            
700 26.5            
700 28 18,4-28 540/75R28     600/65R2  
700 30 16,9-30 480/75R30 480/70R30   540/65R30  
700 30.5         600/60-30,5  
750 26 23,1-26 620/75R26 650/75R26   750/65R26  
750 28     620/70R28      
750 30     600/70R30      
750 32         600/65R32  
750 34 16,9-34   480/70R34 500/70R34 540/65R34  
750 38   400/75R38        
775 30.5            
775 34 18,4-34 520/75R34 520/70R34 540/70R34 600/65R34  
800 30 23,1-30 620/75R30 650/70R30   710/65R30  
800 34   540/75R34 600/70R34      
800 38 16,9-38   480/70R38   540/65R38  
825 30   650/75R30        
825 32 24,5-32 650/75R32 680/70R32      
825 34 20,8-34 620/75R34        
825 38 18,4-38   520/70R38   600/65R38  
875 32 30,5LR32 680/75R32     800/65R32  
875 34   10650/75R3410 680/70R34   750/65R34  
875 38 20,8-38   580/70R38 620/70R38 650/65R38 710/65-38
875 42 18,4-42       600/65R42  
925 34   710/75R34        
925 38   650/75R38 710/70R38   750/65-38  
925 42 20,8-42   580/70R42 620/70R42 650/65R42  
975 32            
975 34            
975 38     800/70R38      
975 42     710/70R42   850/65-42  
975 46 20,8-46   620/70R46   650/65R46  
1025 42   710/75R42        

 

60 - 55 - 45 - 40 series
ETRTO RADIUS RIM ∅ TYRE DIMENSION
Non millim. 60 series 55 series 50 series 45 series 40 series
425 17.5     400/55-17,5      
550 22,5       600/50-22,5 540/45-22,5 710/40-22,5
550 26.5   400/60-26,5        
600 26.5   500/60-26,5        
625 26.5     600/55-26,5   710/45-26,5  
625 28 13,6-28 480/60R28        
650 28 14,9-28 520/60R28        
675 26 18,4-26     750/50R26 750/50-26,5    
675 28 16,9-28 600/60R28        
675 30.5     600/55-30,5 620/55-30,5      
700 26     750/55R26      
700 26.5   650/60-26,5        
700 30 16,9-30 600/60R30        
700 30.5         750/45-30,5  
750 25       1000/50R25    
750 30   710/60R30        
775 30.5   710/60-30,5 800/55-30,5      
775 34 18,4-34 710/55-34       800/50-34
800 38 16,9-38 600/60R38        
825 32 24,5-32 800/60R32        
825 38 18,4-38 650/60-38        
875 32 30,5LR32 850/60-32 900/55R32 1050/50R32    
875 38 20,8-38 710/60R38       850/50-38
925 32   900/60R32        
925 38   850/60-38        
925 42 20,8-42 710/60-42 750/60-42 850/55-42     900/50R42
975 38   900/60R38        
1025 42   900/60R42        

 

 


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The information contained in this publication is for guidance purpose only. Whilst every effort has been taken in its production, no responsibility can be accepted for any loss or damage arising from any kind of undetected technical or commercial error contained in this content. Any data supplied in this publication is subject to possible revision following the date of publication. Due to the constant advance of tyre technology, the contents of this publication are subject to change without notice.