Early Bronco Power Steering Pulleys

Early Bronco Pulley Guide: Single vs Double Groove and Proper Belt Routing

When converting your 66-77 Ford Bronco to power steering, it’s important to look beyond just the steering components and pay close attention to your pulley setup. Many Broncos came with single groove crankshaft and water pump pulleys, which won’t support the added load of a power steering pump. To run power steering correctly, you’ll need to upgrade to double groove pulleys.

With a double groove setup, the inner groove (closest to the engine) typically drives the alternator, while the outer groove (closest to the radiator fan) is used for the power steering pump. This separation ensures proper belt alignment and keeps everything running smoothly without slipping or premature wear.

Some Early Broncos—especially emissions-equipped models—may already have double groove pulleys to run an air supply pump. In those cases, converting to power steering may require a double groove alternator pulley so the air pump can be driven off the alternator, similar to how the 1974-77 Broncos were configured.

Getting your pulley system sorted out from the start will save time and frustration, and ensure your power steering upgrade performs the way it should both on the road and out on the trail.