If you're tired of that vague, wandering feel while cruising, a 73 87 c10 rack and pinion conversion is one of the most transformative upgrades you can pull off in your garage. Anyone who has spent time behind the wheel of a Square Body knows exactly what I'm talking about. You're driving down a straight road, but you're constantly sawing at the wheel just to stay in your own lane. It's part of the charm for some people, sure, but if you actually want to drive your truck through a corner without guessing where the tires are pointed, the factory steering box usually has to go.
The stock steering setup on these trucks was decent for the 70s and 80s, but let's be real—it wasn't designed for performance. It's a recirculating ball system, which is basically a box full of gears and ball bearings that translates your steering input through a series of linkages. Over time, those joints wear out, the box develops "slop," and you end up with three inches of dead space in the steering wheel. Swapping to a rack and pinion changes the entire DNA of the front end. Instead of all those moving parts and pivot points, you get a direct, mechanical link from the steering column to the spindles.
Why the swap makes so much sense
The biggest reason guys go for a 73 87 c10 rack and pinion conversion is purely for the "feel." Modern cars spoiled us. We're used to tight, responsive steering that reacts the second you move your hands. When you drop a rack into an old C10, you're basically bringing that modern geometry to a classic platform. It makes the truck feel smaller, lighter, and way more nimble.
Another huge plus is weight and space. The factory power steering box on a Square Body is a heavy, chunky piece of cast iron. When you pull that out, along with the pitman arm, idler arm, and center link, you're shedding a significant amount of weight off the front nose. Plus, you clear up a ton of room for headers. If you've ever tried to tuck big-tube headers into a small-block or LS-swapped C10, you know the steering box is always in the way. Moving to a rack opens up that engine bay and makes maintenance a whole lot easier.
What you're actually getting into
Now, I won't lie to you—this isn't a twenty-minute job. It's a serious project that requires some planning. Most kits on the market are designed to be "bolt-on," but "bolt-on" in the world of 40-year-old trucks usually means you'll still be doing some drilling, grunting, and maybe a little bit of creative cursing.
The heart of the conversion is a mounting bracket that spans the crossmember. This bracket holds the rack in the perfect position so that the tie rods can reach out to your spindles. Getting this geometry right is the most critical part of the whole thing. If the rack is too high, too low, or shifted too far forward, you'll end up with a nightmare called bump steer. That's when your truck changes direction all by itself just because you hit a pothole. High-quality conversion kits spend a lot of time engineering those brackets to make sure the tie rods stay on the same plane as your control arms.
Managing the power steering pump
One thing people often overlook when doing a 73 87 c10 rack and pinion conversion is the power steering pump. Your old factory pump puts out a lot of pressure—sometimes more than what a modern rack and pinion is designed to handle. If you just hook up your old pump to a new rack, you might find that the steering is too sensitive. It'll feel twitchy, like the truck wants to dart across the road if you even think about turning.
The fix is usually a pressure-reducing valve or just swapping to a pump that's matched to the rack's requirements. If you're doing an LS swap at the same time, this is actually pretty easy to handle with the right pulley and valve setup. Just don't assume you can just jam the old hoses onto the new rack and call it a day. You'll likely need custom high-pressure hoses with the right fittings to bridge the gap between the old-school pump and the metric or O-ring fittings on the rack.
The steering column connection
Connecting your steering wheel to the new rack is where things get a bit "custom." You aren't just bolting a shaft back into a box. You'll usually need a couple of U-joints and a section of DD (double-D) or splined steering shaft. Because the rack sits in a different spot than the old box, the angle of the steering shaft changes.
You have to be careful here to make sure the U-joints aren't at too steep of an angle. If they are, you'll feel a "binding" sensation as you turn the wheel. Most guys find that a two-joint setup works fine, but depending on your headers and your engine placement, you might need a three-joint setup with a support bearing. It's one of those things where you want to mock it up first before you cut anything to length.
Is the turning radius affected?
This is a common question in the C10 community. Sometimes, when you switch to a rack, you might lose a little bit of your turning radius. It's just the nature of the beast—the rack has a specific "stroke" or distance it can move side to side. If that stroke is shorter than what your factory spindles were capable of, your U-turns might get a little wider.
For most people, it's a trade-off they're happy to make. I'd rather have a truck that steers like a laser on the highway and takes an extra point to turn around in a parking lot than a truck that feels like a wet noodle at 70 mph. However, if you're building a dedicated autocross truck, you'll want to look closely at the specs of the kit you're buying to make sure you aren't sacrificing too much maneuverability.
Cost vs. Performance
Let's talk money. A 73 87 c10 rack and pinion conversion isn't exactly cheap. You can spend anywhere from $600 to $2,000 depending on how complete the kit is and whose name is on the box. Compared to just buying a "fast-ratio" steering box for $300, it's a big jump.
But here's the thing: a new steering box is still just a steering box. It's better than a worn-out one, but it doesn't change the fundamental physics of the front end. The rack and pinion setup removes so much mechanical deflection and "junk" from the system that it really does feel like a different truck. If you plan on keeping your C10 for a long time and you actually enjoy driving it on winding roads, it's worth every penny.
Final thoughts on the upgrade
At the end of the day, working on these trucks is all about making them better to live with. We love the Square Body look, but we don't necessarily love the 1973 driving dynamics. Doing a 73 87 c10 rack and pinion conversion bridges that gap perfectly. It's a project that requires some mechanical common sense and a few afternoons in the driveway, but the payoff happens every single time you pull out of your driveway.
You'll stop fighting the steering wheel and start actually enjoying the drive. No more wandering, no more "dead spot" in the middle, and a lot more confidence when you're hauling down the road. Just take your time with the alignment afterward—getting a professional to set your toe and caster once the rack is in is the final step to making sure your truck handles exactly the way you've always wanted it to.