Renewed Steering With Help From A Borgeson New-Gen Saginaw Box

It was more than a few decades ago when the cars that came from Detroit were equipped with manual steering. Back then, that was money-saving standard equipment. If you wanted to enjoy the benefits of power-assisted steering, well, that would cost you a little extra dinero. Now however, the luxury of power-assisted rack-and-pinion – and even electric power steering is – normal to find in a car or truck.


The Saginaw 525 manual-steering box is a simple design that was used for decades. All-new units are once again available through Borgeson, and built to factory specs.

When what we now consider classic muscle cars were just old cars and not something that was revered, many were even the recipient of a so-called “performance upgrade” when well-intentioned owners removed the optionally ordered power-steering box, and installed a manual unit. The reason behind the removal was because “it robbed too much horsepower.”

The sector shafts are received from the foundry as raw forgings, then proceed to have the gear teeth formed on a purpose-built Gleason gear shaper. This is one of the original pieces of Saginaw equipment that Borgeson acquired.

During the ‘80s and early ’90s, finding a manual steering box in a salvage yard was easy. They were plentiful, not yet completely worn out, and swapping them for a power unit could be handled in an afternoon. Now, finding a “good” used steering box in a salvage yard is akin to finding a restorable first-gen Camaro.

Worm gears start out as a special order bar stock, are cut to length, then rough shaped and splined in a CNC lathe. This worm blank then has the correct ratio screw threaded onto it with another purpose-built Saginaw machine and are then sent out to be heat treated. Once they return, the bearing races are turned in a CNC lathe and the thread is finish ground.

Time To Upgrade

Whether your classic has been the recipient of a manual-box swap, or it came from the factory with an Armstrong vehicle-aiming unit, there is no doubt that it’s probably not as firm or tight as it was when it was new. I am willing to bet that the steering box in your hot rod requires you to turn the wheel right or left more than it used to just to initiate a turn. In other words, things have worn out, and it’s gotten “loose” inside. But, you don’t have to settle for a steering box that’s worn and long past its prime. The folks at Borgeson are manufacturing completely brand-new steering boxes for many classic applications.

…the boxes are not only made with the original Saginaw tooling, but also by using the original Saginaw prints. Even much of the equipment used is from the original Saginaw manual-steering gear plant. – Jeff Grantmeyer

Although Borgeson can supply almost anyone with either a power or manual-steering box, we wanted to focus this article on the company’s Saginaw 525 manual unit. This all-new Borgeson steering box is not a rebuilt unit that has been gone through. No sir. This is an all-new box, right down to the casting and all internal parts. It is truly and all-new Saginaw Model 525 manual-steering box, and we’ll explain why later.

Originally, GM used the cast-iron Saginaw 525 beginning in the ‘50s, and continued to install it on many ‘60s and ‘70s-era cars. It was available with either a 24:1 or 16:1 steering ratio. In fact, the 525 was such a popular steering box, that you’ll find they are still occasionally available by scrounging through salvage yards and swap meets. But, why scrounge for a used box if a brand new one is just a call or mouse click away? Let’s clarify. We’re talking a brand new Saginaw box, not an aftermarket equivalent.

steering, Borgeson

Raw housing castings are purchased and machined in-house on specifically built fixtures that allow Borgeson to produce a finished casting in just two operations in the CNC machines.

When it comes to the ratio differences, it breaks down like this: the 24:1 ratio will make the car easier to turn at low speeds, and the steering response will be considerably slow. This is because it will require more revolutions of the steering wheel when turning lock-to-lock than the 16:1-ratio box. The 16:1-ratio box will give you quicker control of the steering (less revolutions of the steering wheel), but on the downside, turning the car while at slow speeds will be slightly harder than with the 24:1-ratio box.

steering, borgeson

Un-machined casting in one of the several set-up fixtures used.

Factory-New Steering

We asked Jeff Grantmeyer, sales manager of Borgeson, what makes this new box such a good upgrade. We were actually surprised with his answer. “The Borgeson steering box is the OE. That’s because in 2014, Borgeson purchased all of the original tooling, equipment, and manufacturing rights for the entire Saginaw manual-steering gear line,” he told us. If that’s the case, what better way to get a brand-new steering box than by getting what is actually a new, original unit?

Top cap: as-cast and finish machined (left). Pre-load adjuster cast and machined (right).

Jeff finished with, “All forgings are done in the USA, and all of the castings are from Canada. We would also like the customer to know that the boxes are not only made with the original Saginaw tooling, but also, by using the original Saginaw prints. Much of the equipment that we use is from the original Saginaw manual-steering gear plant.”


Once all of the parts have undergone a complete inspection, they are assembled.

In a typical tech article, this is where we would start showing you how to install this box and let you know how easy it was – or wasn’t – and then tell you if the swap made any noticeable difference in vehicle performance. But this time, that didn’t seem logical. Let’s face it, if you are installing a new OE-spec steering box, your original unit was probably worn out. That means the benefits of the swap are a no-brainer.


Each Borgeson steering box undergoes a quality control inspection before it leaves the Travelers Rest, South Carolina facility.

This time, we thought we would take you behind the scenes and show you how the Borgeson/Saginaw 525 box is actually made. Take a look at the images and cptions in the article, and see just what goes into making each steering box. Like we said before, this particular product is made right here in the US of A. That means every piece of the Borgeson/Saginaw box is built by American craftsmen.

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About the author

Randy Bolig

Randy Bolig has been working on cars, and involved in the hobby ever since he bought his first car when he was only 14 years old. His passion got him noticed by many locals, and he began to help them with their own vehicles.
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