Rebuilding a Saginaw Rotary Valve Power Steering Gear

Read This Before Working on a Saginaw Rotary Valve Power Steering Gear:

Rebuilding a steering gear requires care and special tools. Resealing and rebuilding a Saginaw Rotary Valve power steering gear can be difficult if you do not have these tools or you lack experience with this kind of work…Rebuilt steering gear assemblies are readily available from a variety of sources, including Cardone, AC-Delco and others. If the reseal or rebuild work shown in this video is more than you care to handle, consider purchasing a rebuild/exchange steering gear from a reputable source…Note that the steering gear shown in this lengthy instructional video is from a 1989 Jeep YJ Wrangler. This gear shares many features with other Saginaw Rotary power steering gears of that era and earlier. However, later model Saginaw units use a different seal configuration and may have other unique features. When rebuilding any steering gear, be certain to use a factory or professional level service manual that covers the specific year, make and model of your vehicle. For a general overview, this video will prove helpful. If you decide that the work takes too much time, skill or tooling, consider purchasing a rebuilt/exchange steering gear assembly from a reputable source.

This in-depth HD video provides the general steps for working on a Saginaw 700 or 800 series power steering gear. These guidelines apply to many Saginaw integral rotary valve power steering gears in the 700 or 800 series. Whether a gear needs re-sealing or a complete overhaul, either on the workbench or in the field, the video will prove helpful. A factory-level or professional shop manual for your specific vehicle will provide necessary details and specifications for working on your gear.  Do not attempt this job without a shop manual or instructions related to your year, make and model vehicle.

Many makes of automobiles, light trucks and SUV models use Saginaw rotary valve integral power steering gears. The “700-series”, “800-series” and similar derivative designs, including the “605” gears, each trace back to Saginaw Gear Division’s patented innovation, the recirculating ball-and-nut, worm and sector mechanism. The Rotary Valve design introduced in 1959 took power steering gear technology into the modern era, features that survive to this day.  

Note:  The 605 gear shares some features with the 700 and 800 series steering gears; however, the 605 design, its parts and service steps differ significantly from these other Saginaw integral power gear types. Know your gear type and its features.  Use a service manual that covers your specific gear’s design and application.

This typical Saginaw 800-series type steering gear is undergoing adjustment on the work bench. Once you have diagnosed a problem with a gear, remove the unit from the vehicle. This gear fits a 1989 Jeep YJ Wrangler.

Note: Begin with the in-chassis troubleshooting feature at the magazine, click here. The troubleshooting feature provides guidelines for performing an in-chassis steering gear diagnosis. You can quickly determine the extent of wear or damage to a Saginaw Rotary Valve integral power steering gear before removing the gear for rebuilding or resealing.

When resealing or rebuilding the Saginaw Rotary Valve integral power gear, the parts to be replaced will be similar for the all Saginaw Rotary Valve integral power steering gears. The OEM or aftermarket “complete rebuild kit” will include specific parts for the year, model and casting number of the gear. When identifying a Saginaw gear or ordering parts, be certain to note the year, model and, most importantly, the casting number of the steering gear being serviced.

Here, a Jeep XJ Cherokee Saginaw power gear undergoes troubleshooting in the chassis.

This how-to project’s prototype vehicle is a Jeep® YJ Wrangler. The YJ’s Saginaw power gear shares features and service procedures with other Saginaw Rotary Valve integral power steering gear applications. This includes common dis-assembly steps, inspection procedures and safety concerns that apply when rebuilding any Saginaw rotary valve integral power steering gear built from 1959 onward.

The bore of this Saginaw power steering gear is scored beyond service. An attempt to “hone” a cylinder worn this badly will prove futile. A new or rebuildable gear housing is required here.

The Jeep® YJ Wrangler gear is the popular four-bolt cover “800 Series” gear design. The procedures shown in this how-to video provide the basic steps and concerns for working on other Saginaw Rotary Valve power steering gears as well. The information proves helpful for rebuilding any Saginaw integral rotary valve power steering gear, including the round sector cover “605” style gear.

When rebuilding a Saginaw 605 gear, refer to the factory service manual service steps and specifications that apply specifically to that gear. This how-to video is in-depth and specific to the common 4-bolt cover (700- and 800-series) gears. Many of these service steps and safety concerns also apply to the 605 gear.

Key distinctions when ordering parts are the power piston bore size and the splined shaft/seal diameters. When setting up a Saginaw integral power steering gear, always use the torque tightening and adjustment specifications for the specific year, make and model vehicle. The casting number on the steering gear housing is a significant identification feature for any Saginaw steering gear.

For additional information on Saginaw power steering and other technical topics, visit the magazine’s forums!