WHEEL NUT/STUD SIZES NEW METRIC SIZE THREADS

VEHICLES AFFECTED: 1988 GM 'C-K' TRUCKS

The all new 1988 C/K series pick-up trucks will use new M14 X 1.5 thread size wheel nuts and studs. This is the first usage for this metric size on any GM vehicle. Care must be taken so that the correct size nuts are used with their exact corresponding size studs. If intermixed, stripped threads and/or improper torques could result. Metric nuts are stamped with the word "METRIC". Metric studs may be stamped with an "M" or "METRIC". The following chart should be helpful in determining wheel nut/stud sizes for all 1988 GM vehicles:

THREAD SIZE WRENCH SIZE TRUCK APPLICATION CAR APPLICATION M12XI.5 19mm "S" & "T" TRUCK ALL EXCEPT "B" & "D" *Ml4 X 1.5 22MM "C" & 'K" TRUCK ----- 7/16-20 3/4 IN V-10 (6 BOLT) " B " CAR 1/2-20 13/16 IN G-10, G-20, R-10 " B " WAGONS, "D" CAR M-VAN (5 BOLT) 9/16-18 7/8 IN R-20, R-30, V-20, ----- G-30 (B BOLT) *NEW FOR 1988 "C-K" MODELS

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.