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How to Check Automatic Transmission Fluid
It is not necessary to check the transmission fluid level. A transmission fluid leak is the only reason for fluid loss. If a leak occurs, take the vehicle to your dealer and have it repaired as so ...

Powertrain details
The GMC Sierra All Terrain HD concept is propelled by the new, production 6.6L Duramax turbo-diesel V-8 and Allison 1000 six-speed automatic transmission powertrain combination offered in the 2011 ...

Hydraulic Power Steering
Your vehicle has hydraulic power steering. It may require maintenance. See Power Steering Fluid on page 10‑21. If power steering assist is lost due to a system malfunction, the vehicle can be s ...