S10/T10 Blazer 2WD L4-121 2.0L VIN Y 2-bbl (1983)
part number 8635909 (one piston and one seal per package). The oil seal is available separately as service part number 8635568.
Important:
The same design accumulator piston and seal are used in both the 1-2 and 3-4 circuits.
Refer to the appropriate Service Manual for removal and installation procedures.