Fluid · Manual Transmission
Manual Transmission
for 1971 GMC C2500 250ci I6 · RWD
Fluid Type
Dexron II ATF or 80W gear oil
Spec: GM Type A or API GL-3
Capacity
3.5qt
3.31 L
Drain & Refill
3.5 qt
3.31 L
Change Interval
24,000 mi
38,616 km
Data quality
Book-style estimate
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Notes
SM420 or SM465 4-speed manual. GM recommended ATF for smoother shifting; gear oil acceptable.