What in the heck is a John Deere GM, anyway?

Ray & Diane Miedema’s Tractor Collection

The John Deere GM is a bit of an interesting footnote in the G’s story, and a neat one at that. And since I’ve never written about the G—or the GM—this feels like a good time to change that. And I was flipping through Mecum’s listings recently, one in particular caught my eye: a 1942 John Deere GM.

Quick side note: this is an online-only sale hosted by Mecum Auctions. The collection is in Holmen, WI, just northeast of La Crosse. In-person previews run August 8–9, and bidding starts closing at 10AM on August 9, 2025.

Now then—there were three main generations of the G: unstyled (1937–1941), the GM (1942–1947), and styled (1948–1953). Let’s dig in.

The G stands for “gorilla”

Okay, so the G didn’t actually stand for anything. Deere had already used every letter up to E by 1937—except for the letter F. Frank Silloway, their VP of Sales, insisted they skip it to avoid confusion with Farmall’s F-series. Probably a smart call…though ironically, both Deere and IHC ended up with a Model H by 1939 anyway.

Back then, Deere was behind in the horsepower race. IHC had launched the F-30 in ’31. While they hadn’t sold a ton of them, the F-30 packed more punch than John Deere A. So in 1936, Deere started developing what became the G. The prototypes, codenamed KX, tested well in the Midwest. It was Deere’s biggest row crop to date, hence the joke about the G standing for “gorilla”—rated at 27.6 horses on the drawbar and nearly 36 on the belt. And if the pricing model I’ve heard was correct, farmers could bring one home for about $1100, which is a pretty solid bang for the buck.

Heating things up—literally

While Deere’s early testing went well. The new engine—big but not quite as big as the one in the D—was a 413-cube two-cylinder with a 6⅛” bore and a 7″ stroke. It ran strong and the feedback was good, so Waterloo green-lit the project and they went into production in May of ’37.

However, it wasn’t perfect. Deere misjudged how much cooling it needed. So when the summer weather hit, farmers had problems with overheating—especially in the Southern states. The first 3250 machines had to be recalled. And it wasn’t just a radiator swap. The fix included a taller radiator and shutter, new fan and shroud, redesigned hood and fuel tank, and deeper-set exhaust valves to keep things running cooler.

Despite the misstep, Deere stuck with the G. They knew it had potential. By the time the unstyled version wrapped production on December 22nd, 1941, they’d built just under 10,700 of them. The last unstyled G serial number was 12193.

Speaking of styled vs. unstyled, let’s talk about the advent of style in tractors, because it becomes pretty important in the late 30s.

Styling and streamlining

For years, tractors weren’t much to look at. They were tools. Everything was exposed—engines, radiators, linkages—and nobody really cared. But by the late ’30s, that started to change. Some of it was aesthetics. Some of it was practical protection for important parts. Maybe it was both.

Regardless, it seems like, for the most part, the move towards styled tractors happened in the 1937-38 timeframe. With the exception of Oliver, who I believe handled styling in-house, all the big hitters aligned themselves with well-known industrial designers. Allis brought in Brooks Stevens, IH tapped Raymond Loewy, and Deere partnered with Henry Dreyfuss.

Dreyfuss started with the A and B in 1939, adding sheet metal and sculpted fenders that gave tractors a sleeker, more modern look. Customers liked it, so Deere kept going—with the G next on the list late in 1941.

The G gets a glow-up…

The updated G wasn’t just prettier—it was stronger too. Dreyfuss restyled the hood and fenders. Meanwhile, Deere engineers squeezed more power from the engine and swapped in a new 6-speed transmission.

But there was a catch.

When the U.S. entered WWII, the government formed the Office of Price Administration to keep inflation in check. One rule? You couldn’t raise prices on things like tractors—unless you could prove it was a brand-new (or substantially improved) model.

This was a problem. Deere had just poured money into the G’s improvements. So, they doubled down, added a few new features (like optional electric start and electric lights), and pitched it as the “GM”—G Modernized. And wouldn’t you know it? The OPA approved it, and production began on February 20th, 1942 with serial number 13000.

Was it a stretch? Maybe. But honestly, I think you could argue it either way.

Fits and starts…

Even so, GM production didn’t last long before hitting a major speed bump. Just as things were ramping up, Deere had to hit pause on September 21, 1942 with serial number 13747. It wasn’t a performance issue—it was wartime rationing. The OPA controlled how much steel companies could use, and Deere had to prioritize their best sellers. Since the A and B were still outselling the GM, it got benched for the time being.

Production stayed on hold for more than two years, finally resuming on October 16, 1944 as the end of WWII came into sight. Once the line fired back up, Deere didn’t hold back—and neither did their customers. With machines finally available again, sales of the GM picked up steam fast. By 1947, they were back in line with pre-war numbers for the unstyled G.

The G is back!

Once the OPA lifted wartime restrictions, Deere immediately made plans to incorporate the styling and performance enhancements of the GM back into the original G. The GM name had always been a bit of an outlier, and I think the lack of consistency bothered them. The final GM rolled off the line in early March 1947 (serial number 22112), and by March 7, Deere had kicked off production of the newly styled G with serial number 23000.

Over the next few years, Deere kept improving the G. They had it retested at the Nebraska Tractor Test Lab and started rolling out new versions. Until 1947, the G was only available in the tricycle front-end style. But that year, Deere introduced two more options: the single front wheel version (GN) and the wide front version (GW). The high-crop model (GH) came along in 1951.

By 1952, Deere felt they had taken the G as far as it could go. It was replaced by the 70 for the 1953 model year.

Was the G (and GM) a success?

All told, Deere built close to 64,000 Gs between 1937 and 1953. In my book, that qualifies as a pretty successful venture! And in a lot of ways, the G pointed to where farming was headed. As soldiers came home from WWII and started farms of their own, they needed tractors capable of growing with them—and Deere was ready. The G gave them the muscle they needed, as well as room to grow.

Today, the G is still a favorite. They’re very much at home in collections, parades, and you’ll still find one working on a small farm here and there as well. They’re mainstays at shows, tractor rides, and antique tractor pulls—and that’s not changing anytime soon.

What isn’t all that common, though, is finding one with a GM tag. That’s part of what makes Ray Miedema’s tractor stand out. So let’s take a minute and talk about that one.

The John Deere GM you can buy on August 9th…

Unfortunately, I couldn’t connect with Ray to talk about the collection, but that’s part of the deal sometimes. What I can tell you is that he had a soft spot for Deere’s letter-series machines. All told, there are nine Gs in the auction—including a pair of sequentially numbered unstyled ‘38s—along with 14 As and 20 Bs. Some run, some are pullers, some need work, and a few are probably parts donors. But together, they’re a solid tribute to the iron that helped feed America.

The 1942 GM featured in most of these photos is likely the star of the sale. Ray and Diane restored it together about 20 years ago, and it’s made the rounds at plenty of shows since. In 2007, it earned a Two-Cylinder Club “Expo Quality Restoration” award—an honor they stopped handing out after founder Jack Cherry passed. Ray’s was #133, and in my book, that’s no small feat.

Outside the green stuff, Ray also had a handful of Massey-Harris tractors, plus a few strays from Allis, Moline, Harvester, and Ford. Nothing wild or exotic—just well-worn pieces that tell their own stories. It’s a great catalog. Definitely worth a scroll.

Wrapping up…

It’s always a little humbling to scroll through a collection like this. Some shine, some don’t, but every one of ’em has a story. Now it’s time for new owners to write the next chapters. Whether you’re looking for a project, a showpiece, or just an excuse to haul another two-banger home, there’s probably something here that’ll catch your eye. If you’re in the neighborhood—or even if you’re not—this is a sale worth watching.

Here’s the link one more time.

Ray & Diane Miedema’s Tractor Collection