2015 Chevrolet Silverado 1500 Transmission Types & Fluid

Identify your transmission first

The 4.3L V6 and common 5.3L configurations used a six-speed automatic, while the 6.2L V8 was paired with an eight-speed in Chevrolet’s 2015 brochure. Do not identify the gearbox using engine size alone when working on a truck with unknown history: confirm the RPO codes or VIN build data.

Fluid checks and service

The 2015 GM owner manual lists DEXRON-VI for automatic transmissions other than the 6.2L eight-speed, and DEXRON-HP for the 6.2L eight-speed (original GM fluid numbers 19300536 US / 19300537 Canada). Those are the original publication specifications. GM later issued updated eight-speed service procedures and fluids for certain shudder concerns; check the latest VIN-applicable service bulletin before a fluid exchange. Fluid level and temperature procedures differ by transmission.

• Check the transmission RPO/build information before purchasing fluid.
• A pan service and a completely dry fill require different quantities.
• Never mix transmission fluids on the assumption that all 2015 Silverados are identical.

Why fluid quantity is not a single number

A partial pan drain, cooler-line repair and complete overhaul each leave different amounts of fluid in the system. The correct level is established with the specified temperature and check procedure, not by pouring in a catalogue “capacity.” Too much or too little fluid can cause shifting faults and damage.

Six-speed versus eight-speed service interval

For severe service, the 2015 schedule lists automatic transmission fluid and filter changes at 45,000 miles (72,000 km), then at 90,000 and 135,000 miles. Normal-service requirements differ. Frequent trailer towing, heavy loads and commercial use deserve particular attention to the severe-service definition.