C 2500 Truck 2WD V8-393 6.5L DSL Turbo VIN S (1995)
Coolant: Technical Service Bulletins
Engine Coolant - Information on Back Service
File In Section: 6 - Engine
Bulletin No: 53-62-02
Date: November, 1995
Subject:
DEX-COOL(TM) Engine Coolant - Information on Back service
Models:
1994-95 Passenger Cars and Trucks
A new extended-life engine coolant called DEX-COOL(TM) is currently being used in all General Motors' vehicles (excluding Chevrolet Geo and
Saturn). Refer to bulletin 53-62-01 for general service information.
Backservice
DEX-COOL(TM) may be used in General Motors vehicles originally built with conventional (green) coolant with the following considerations:
^
Vehicles eligible for back service are 1994 and 1995 models (excluding 1994 J Body with 4 cylinder engines).
^
The service interval for DEX-COOL(TM) introduced into an older model vehicle originally built with "green" coolant will be 2 years/30,000 miles
(50,000 Km) (not 5 years/100,000 miles (160,000 Km)).
^
All the "green" coolant must be removed from the cooling system by means of a system flush. This may be accomplished with a water flushing
device or a GMDE waterless coolant changer (use a unit dedicated to "green" coolant, not DEX-COOL TM).
Important:
When using a GMDE waterless coolant changer, conduct the procedure twice, once with water, and once with DEX-COOL(TM)
Backservice with DEX-COOL(TM) is advocated because of enhanced water pump seal durability experienced with this coolant.