Tires - General Information
86bmw06GROUP 36 Wheels and Tires
Bulletin Number 36 03 86 (1303) Page 1 of 3
Montvale, NJ December 1986 Technical Dept.
SUBJECT: General Tire Information
Situation: For the 1987/88 model years, several high-performance vehicles are included in the model line up. Under certain conditions, extreme loads may be imposed on the tires of these vehicles.
For this reason it is important that only the specified tire size as listed in the Owner's Handbook be used. The specification parameters of tire size, load rating and speed rating must all be met when installing new tires.
To aid you in understanding the various designations on a tire sidewall, we are illustrating same with numbered callouts and accompanying explanations on the following pages.
INFORMATION ON TIRE SIDEWALL
EXPLANATION OF TIRE SIDEWALL INFORMATION
1: 175 - Rated tire width in mm
2: 70 - Tire height to rated tire width ratio in %
3: R - Radial (TR = Tension Repartie = Tension Distribution)
4: 14 - Rim diameter in inches
5: Load index: Maximum load per tire in lbs.
84 = 1102 89 = 1278
85 = 1135 90 = 1323
86 = 1168 91 = 1356
87 = 1201 92 = 1389
88 = 1234 93 = 1433
6: Speed symbols: maximum speed tire has been designed for.
Q = 100 T = 118
R = 105 U = 124 V = faster than 130
S = 112 H = 130
7: Radial - type of tire
8: Tubeless - tire without tube
9: Match point (green dot on side of tire with DOT data)
10: Sidewall 2 ply 2 rayon - structure of tire body
11: Tread 5 ply 2 rayon 2 steel 1 nylon - structure of tire treads
12: TWI - Treadwear Indicator - visual indicator for tread wear
13: Loads and pressures for North America
14: Max. load 1105 LBS. - max. load in pounds
15: Max. pressure 36 LBS/SQ IN - max. inflation pressure in pounds per square inch
16: Dunlop 175/70 R 14 84T - tire make, tire designation
17: E4/020608 - tire to ECE standards/test loc. code, serial number
18: CB102 - mfg. internal code number or tread code number
19: SP 4 EXTRA - type designation of manufacturer
20: DOT - Department of Transportation (USA)
21: DN - manufacturer's code for Dunlop
22: HR - code for tire size 175/70 R 14
23: RX2 - type code for SP 4 EXTRA
24: 354 - 35th production week of 1984
25: Traction A Temperature B - wet surface traction A, temperature resistance B
(US Standards)
26: 604 2U - manufacturer's internal code for tooling