Power Steering Flush for Pickup Trucks

The pickup world split in two over the last fifteen years. Ford moved the F-150 to electric power steering in the 2011 model year, and other makers followed on their light-duty trucks, while plenty of mid-size, heavy-duty and older pickups kept the hydraulic pump, reservoir and hoses. The first thing our technician does is look under the hood and tell you which kind you have.

How to tell which system your truck has

• A small reservoir with a cap marked for power steering fluid means hydraulic
• A pump driven by the serpentine belt, with high-pressure hoses, means hydraulic
• No reservoir and a steering motor on the column or rack means electric
• The owner's manual lists power steering fluid only if the truck uses it

Why trucks are harder on hydraulic steering

Big tires, heavy front ends and low-speed maneuvering work a steering pump harder than a sedan ever does. Backing a trailer down the ramp at Pyramid Lake, cranking the wheel lock to lock in a feed store lot in Minden, or crawling a ranch road in the Pine Nuts all push the pump near its relief pressure, and that heats the fluid. Hot fluid oxidizes and darkens, and the rubber in the hoses and seals slowly sheds into it.

Cold is the other stress. Minden averages 75 nights a year at 20 F or colder (NOAA 1991-2020 normals), and thick, worn fluid on a cold morning makes the pump groan and the wheel feel heavy for the first few blocks.

When the flush is due

Many truck makers publish no fixed power steering interval and ask for inspection at regular service, and the Car Care Council's advice is the same: check the level and condition regularly and change the fluid when it has darkened or as the manual directs. Some guides list a change under special operating conditions, and Ford's scheduled maintenance guide is built around those conditions for trucks that tow or idle. We look at the fluid on every truck oil change.

The flush on a truck

If the steering whines on cold mornings, drive in and let us look at the fluid before the pump pays for it.

1. Show you the fluid and the reservoir before any work.
2. Quote it in writing if it is due, per NRS 487.6875 for work over fifty dollars.
3. Remove the old fluid and purge the lines with the specified fluid, which may be ATF or a dedicated power steering fluid depending on the maker.
4. Cycle the steering lock to lock to bleed air, then recheck the level.