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In 1935 Ab Jenkins Went 68mph On An Allis Chalmers Tractor And In 2014 There’s a Modified 8N Showing Up To Blow That Away

In 1935 Ab Jenkins Went 68mph On An Allis Chalmers Tractor And In 2014 There’s a Modified 8N Showing Up To Blow That Away

The man you see hunkered over the steering wheel of that (literally) speeding Allis-Chalmers tractor is the legendary Ab Jenkins. In 1935 Jenkins drove that tractor to a terminal speed of just under 68mph to set the “land speed record” for a tractor.  Jack Donohue has a modified 1948 Ford 8N to blow that number to smithereens. If you think I am making any of this up, I am not. History is on my side along with the historic photos and news clippings below. We were tipped off to the Donohue effort by Stuart Hall who was surprised that we had not mentioned it. The only reason we have not mentioned it is because we had no idea about it because trust us, if we knew this was happening we’d have been giving you hourly updates. So now…onto the story.

abjenkins3In the 1930s, it was uncommon for farmers to put rubber tires on their tractors. Steel wheels were far more prevalent at that time and tire companies were paying attention to this massive market that they wanted to break into. Previous efforts at convincing farmers that a switch to rubber tires would save them fuel and allow them to cruise at relatively high speeds down many of the newly paved country roads that they could not travel down in their steel cleated tractors. Allis-Chalmers led the way on this front as far as OEM builders and made rubber tires standard equipment on their machines in 1932. Firestone engineered a tire that would carry a relatively low air pressure and have a relatively flexible sidewall. The company was aggressively trying to promote this idea to farmers and wasn’t having a whole bunch of success. Remember, the Great Depression was on and money wasn’t exactly flying around the farm. Rubber tire tractors started winning plowing competitions and winning them by a pretty good swath. From that development came an idea (from the advertising department at Allis-Chalmers) to do some high speed running with the tractors. At a time when most tractors would run to about 10mph in their meager “road gear” this idea was nearly comical….but people listened.

Suddenly the engineering department developed a very tall drive ratio for the tractors. Unfortunately it has been lost to history how they actually derived this ratio. We presume it was a combo of a taller 4th gear in the transmission and a taller ring and pinion gear. These things were literally set up to go where no tractor had gone firestonebefore…or since. The first demonstration of the racing tractor saw a race driver take it around a track at 35mph in front of a stunned crowd, the big Firestone tires polished up and gleaming in the sun. The company really stepped up the program and hired an aging but still legendary Barney Oldfield and he managed a speed over over 64mph on a measured course at a county fair. This became big news…and all of a sudden those tires didn’t seem like such a bad idea. Incidentally, Ab Jenkins was the second touring “racer” and he stole the record from Oldfield by topping 65mph with Harvey Firestone himself present to see the feat. These guys barnstormed HARD, covering seven states in a short span of weeks to spread the word.

While the schedule was not as aggressive in 1935, the company was still working the message and Ab Jenkins, who was already planning another series of speed trials on his beloved salt flats in the Mormon Meteor, dragged along a speedy Allis Chalmers to use as a bit of a warm up act before the main event. The result? He clocked a speed of nearly 68mph, resetting the mark he had made a year earlier during the Harvey Firestone attended adventure in Ohio. How did it go? Multiple reports claim that when asked how the tractor rode at speed, he described it as being atop a, “frightened bison.” There’s good reason the tractor speed attempts by Jenkins stopped then. The guy was smart enough to know that he didn’t want to survive all his other accomplishments only to meet his maker driving a tractor.

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So…..to the present day!

The tractor that we’re hoping to see on the Ohio Mile someday has been constructed by one Jack Donohue and it is called 8N Incredible. There are photos of the machine online and we’ll show you a few below as well as direct you to the Jack Donohue Motorsports website for more. While we cannot see the whole machine we can tell you that it is powered by a flathead V8 much like an old Funk converted 8N would have been. We can tell you that the rear tires are aviation tires that came from a large jet and stand nearly six feet tall and we can tell you that there is some beautiful fabrication work done to this hopefully fastest tractor in the world.

Donohue builds race cars for a living and grew up around stock cars racing, even driving in NASCAR during his racing career. He’s a native of the Carolinas and still lives there, operating the aforementioned Jack Donohue Motorsports operation out of the town of Fletcher. Donohue was raised on a farm and can still remember the day when his dad rolled up in a gleaming new 1952 8N. That sparked a love affair that has lasted a lifetime. He’s been fixing and restoring the tractors on the side for as long as he can remember and dreaming about the chance to build a speedy one to take on Ab Jenkins longstanding record.

That’s about all we really know at this point. The whole thing is a bit of a glorious mystery. Stuart, who gave us the tip is passing along a number that we’ll call and harass Jack on to give you a more in-depth look at the project. Anyone who has ever driven a tractor “fast” (like 20) knows that things can get weird in the steering in a hurry. We have to guess that Jack’s race car building and racing experience have allowed him to work on that. We sure hope that it has. We’re going to share with you some photos from the Jack Donohue Motorsports website below and you can take it from there.


8N5 8N4 8N3 8N2 8N1


CLICK HERE to read all about 8N Credible and see more photos

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12 thoughts on “In 1935 Ab Jenkins Went 68mph On An Allis Chalmers Tractor And In 2014 There’s a Modified 8N Showing Up To Blow That Away

  1. ahren

    I have a 1933 Allis Chalmers model U like the one above. Allis put a hidden high speed gear in some of them to achieve the high mph’s. Mine has that hiddin gear. I have had mine north of 40mph but with farm tires. You have to think, this tractor has no floor you are stradling the rear axle housing and trans. They weigh about 5000#’s and there are no wheel brakes, just a hand brake on the transmission. They raced these tractors at county fairs in the 30’s also.

  2. Threedoor

    So cool! I just got a Model M from my step grandfather, in 5th at 15 or so its a handful cant imagine any faster.

  3. ratpatrol66

    I have a 44 2N Ford that is a handful in 3rd at maybe 18. This guy is a nut, and has a big set.

  4. Jay Bree

    Once, around 1971, I thought it would be a good idea to put the Ford tractor (equipped with front loader and rear backhoe) into neutral and coast down a big hill on a dirt road.

    About halfway down, I was torn between trying to ride it out, or attempting to bail. I made the right decision and hung on to it as it careened out of control down the hill.

    When you mention tractor steering gets weird above about 20, you’re not lying….

  5. oletrux

    I’m gonna watch the coverage just to see how this work out! I agree with the trailer comment above………spent half my life on a tractor, and this is a great, yet crazy project.

  6. Ted Shannon

    Purpose built tractor, and I use that term loosely, to beat Jenkins record takes some of the luster off of the story. If the tractor Donohue was using was the twin to the one that set the record that would be worth following. Sorry, using dynamite to kill ants just ain’t newsworthy.

  7. Joe Roberts

    I have seen a video somewhere of Ab Jenkins on the tractor at Bonneville. I that was way crazy. Now this fellow is out after the record…..I think maybe he is even crazier. From what I have heard about the weather on the salt right now he might be the only one able to make a pass… My hat is off to this guy and wish him much success.

  8. Matthew Quinn

    It is sad that all allis did was some modification to4th gear and the ford has to be modified a lot when you look at the pic jack Donahue is having to modifie the hell out of an 8n hell why don’t I put a tractor hood on my stock car and go after it really .

  9. Shane Masters

    I agree with Mathew Quinn I read the article it is bull how bout I take my u and put in a v8 change ring and pinion have head polish like done put big carb on change 4 gear and sub frame it if jack breaks it hes a joke hope he burns it up and the trany explodes talk about cheating

  10. Allis Foever

    Ab Jenkin’s Allis-Chalmers tractor was road geared stock machine. I think for fairness, Jack Donahues Ford should be comparable. From Jacks photos, there seems to be a subframe, roll guard, and who knows what else in the drivetrain??? Jacks racing a car that has a few tractor parts attached to it – not the same….

  11. S. Moore

    You guys are forgetting that if you want to run on the salt you are required by SCTA to have the proper safety equipment, hence the cage and all the other “required” safety equipment. Also, I bet you this tractor weighs a heck of a lot more than the old allis-charmers.

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