Tires are usually named with a series of codes. For example, one of the recommended tires for Vanagons is the ‘Yohohama Y356 LT 195/75 R14 (load range D)’. The latter part of this (195/75 R14) is a uniform code assigned to tires. This section tells you how to interpret this code.
Speed Rating
Sustained speed rating is designated by a letter code. Vanagons require a minimum speed rating of ‘R’. (Don’t be confused with ‘R’, though. In ‘195/75 R14’, the ‘R’ is means ‘radial’ and is not a speed rating.)
Q 99 mph 160 kph
R 106 mph 170 kph
S 112 mph 180 kph
T 118 mph 190 kph
U 124 mph 200 kph
H 130 mph 210 kph
V 149 mph 240 kph
W 270 kph
Y 300 kph
Z 149+ mph 240+ kph
(I’m not sure why ‘H’ is in there, except that some person thought it would be cool if ‘H’ stood for ‘high speed’.)
Tire widths
Wheel diameters are usually in inches and tire width in millimeters or a letter designation. In our example of ‘195/75 R14’, ‘195’ is the tire width in millimeters, and ’14’ is the wheel diameter in inches.
mm letter inches
80 MH 3.00
90 MJ 3.25
100 ML 3.50
110 MM 4.00
120 MP 4.50
130 MT 5.00
140 MU 5.50
150 MV 6.00
Shoulder heights
The shoulder height is stated as a percentage of the tire width. For example, in ‘195/75 R14’, the shoulder height is 75% of the tire width (195mm), or 146.25mm.
Load index
The load-index figure denotes the maximum load capacity of a tire when driven at maximum speed. Note that you have four tires, so you should multiply the load index value by approximately 4.
Vanagons & Syncros need a load rating of at least 97, while Syncro 16″ need a load rating of 104. In the chart below LI stands for Load Index and KG is Kilograms.
LI KG LI KG LI KG
65 290 83 487 101 825
66 300 84 500 102 850
67 307 85 515 103 875
68 315 86 530 104 900
69 325 87 545 105 925
70 335 88 560 106 950
71 345 89 580 107 975
72 355 90 600 108 1000
73 365 91 615 109 1030
74 375 92 630 110 1060
75 387 93 650 111 1090
76 400 94 670 112 1120
77 412 95 690 113 1150
78 425 96 710 114 1180
79 237 97 730 115 1215
80 450 98 750 116 1250
81 462 99 775 117 1285
82 475 100 800 118 1320
119 1360
Miscellaneous codes
P Passenger
LT Light Truck
R Radial
B Belted
Tire Diameters
What is the diameter of a tire?
Here’s a table of tire diameters by width and profile, for your speedometer correction calculations. Eurotire, a nice-to-deal-with tire distributor in NJ, used to include this info and more in their catalogs.
14 inch wheels:
80 75 70 65 60 55
165 622 — — — — —
175 634 — 606 — — —
185 650 631 624 596 578 —
195 — 651 636 605 590 —
205 — — 652 — 602 582
215 — — 665 — — —
225 — — — — 626 604
245 — — — — 650 —
15 inch wheels:
80 75 70 65 60 55
165 646 — — — — —
175 660 — 632 — — —
185 674 — 648 621 — —
195 — — 656 635 615 —
205 — 681 669 647 627 607
215 — 692 682 661 639 —
225 — 694 — — — —
235 — — — — 663 639
265 — — — — 687 —
Diameters are in millimeters, with tire installed on narrowest rims approved for that tire size. Wider rims would give slightly smaller diameter.