Power Steering Upgrade 1999 Ford F550 Power Steering Rebuild View With Serpentine Belt Removed

Power Steering Upgrade on a 1999 Ford F550

It Was Time for Some Open-Heart Surgery on That All-Important Steering System

From the May, 2012 issue of 8-Lug

Author: Gary Wescott

Photography: Gary Wescott

Power Steering Upgrade 1999 Ford F550 Powersteering Rebuild Powersteering Surgery

So you’re driving an eight-lug heavy-duty truck. It just doesn’t get any tougher, does it? Over the last 30 years or so, Ford, Dodge, and GM/Chevy have listened to their customers. Cool stuff that owners used to add now come stock or at least as an option: comfortable bucket seats (when’s the last time you sat in a bench seat?), power everything, steps, bigger engines, and more. It’s a long list of great improvements, but the result has been an accent on the “heavy” of your heavy-duty truck.

According to Tom Lee, owner of Lee’s Power Steering in Sun Valley, California, one of the few systems that has not changed since the ’60s is the steering pump and steering gearbox. Tom should know—he established Lee Manufacturing in 1965 and has earned the reputation as an undisputed authority on performance steering. From military applications and desert racing sprint cars to stock cars and Formula One, many winners have crossed the finish line with Tom’s steering systems.

Arguably, steering is the most important part of your vehicle. Think about it. No matter what else works, your steering is the key. No matter how fast or slow you might be going, or what the situation is, if you can’t steer, you are in big trouble. Really big trouble!

When we started to hear a couple of horror stories about pre-’04 Ford sector shafts cracking or breaking, we decided to take a closer look. As it turns out, it’s not just a Ford problem. The crack is often instigated by overtightening the nut, which forces the Pitman arm over the end of the splined end of the shaft. If you have a stock truck and drive it normally, there’s less chance of a problem other than sloppy control. On the other hand, if you’ve lifted your truck, added some 40-inch rubber, and drive aggressively on roads that might keep Detroit engineers awake, you can’t really blame the OEM if something breaks.

There have been cases of broken sector shafts, in some instances with catastrophic results. As we begin final preparations for a three-year expedition following the infamous Silk Road across Europe and Asia, every system on our ’99 F-550 must be in absolute top condition. Our 14,000-pound loaded GVW and the 40.7-inch Michelin XZL tires put additional stress on the entire steering system.

First of all, you might not even know what a sector shaft is. It’s the round thingy sticking out the bottom of your steering gearbox. The Pitman arm attaches to it with a big bolt, and that’s connected to the drag link, which ultimately connects to your hand on the steering wheel. In other words, it’s the final mechanical link between you and the direction your truck is moving—even if everything else is dead.