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Uncle Mike’s Flat-Ulence

A vintage sleeper Flatfender Jeep that works.

If you like old Jeeps of the flat-fendered variety, you'd have to be living under a rock to not know that they, in relatively stock form, are having something of a revival in the off-road world. Social media is littered with images and videos of modern folks wheeling vintage military and civilian flatfenders in places most folks didn't realize these venerable rigs could go. Sure, some have been "in the know" of what the first readily available 4x4s are capable of, and in a time of social distancing and exploration taking to these original off-road rigs is like a fly drawn to honey. Our buddy Mike Tarvin has been in the know when it comes to Jeeps for 30 or 40 years. He's a man of many hats, and one hat that he can confidently wear is that of an old Jeep expert. He has several older Jeeps including (at least) two flatfenders (that are in one piece and running) including this one, a mixture of parts we will call a 1946 CJ-2a, cobbled together from a bevvy of parts from a multitude of different early Jeeps that Mike has collected over the years. Mike claims he has about $1,200 in the Jeep, and he may not be far off from that number since he is good at finding old Jeep parts and getting a deal. The name of the Jeep is Flat-ulence 'cause it's funny, and, truth be told, the Jeep does have a bit of an odor.

Vintage Jeep Powerplant

Yeah, it's got a little bit of a knock, but this $100 Go Devil 134 L-head four-cylinder Mike got from a fellow collector for a steal gets the job done without burning up too much oil. The engine is fueled by a Carter WO rebuilt by Old Jeep Carbs LLC. The engine has been converted to 12-V and runs a 1-wire GM alternator. Mike runs the points in the stock distributor, which fires a well-hidden MSD box that feeds an MSD vibration-resistant coil. Mike likes his spark hot, and so does the L-head. Exhaust leaves via a 2-inch custom full-length exhaust from Big Jim's Mufflers in Phoenix, Arizona.

Trick Jeep Transmission with a Granny Gear

A T-98 from an early CJ5 with the 6.4:1 first gear backs the L-head and gives Mike gobs of low-end gearing and a second gear with a ratio close to that of a stock T-90 so Mike can still bump obstacles if need be. Swapping a T-98 behind an L-head is an old-school Jeeper trick that has become more and more difficult as these relatively rare transmissions have aged.

Jeep Spicer 18 with a Warn OD

Behind the T-98 Mike rebuilt a Spicer 18 transfer case using a later case that uses the 1 inch intermediate shaft, the strongest one built. Behind the Spicer 18 and usable in any gear including the reverse gears Mike rebuilt a Warn Overdrive. Mike is a big fan of splitting gears on the road to keep those high-speed (45-mph) rpms down.

Old-School Tricks in Vintage Jeep Axles

The axles under Flat-ulence are an early CJ-3A Dana 44 with a 19-spline Detroit turning old-school one-piece flanged Summers Brothers axle shafts. The front axle is an MB Dana 25 with Brennan's Garage disc brakes, a two-hole knuckle on the passenger side (one for the drag link, one for the tie rod), a Power-Lok differential with fresh clutches, and Spicer axle shafts. A pair of Cutlass Hubs unlock the front wheels when the flattie sees tarmac. Both axles spin via 5.38:1 ring-and-pinions

Jeep Frame and Body

Mike, a collector of all things old Jeep related came across the frame for flat-ulence a few years back. The tale is that it was originally used under a DJ/Surry CJ-2A, and Mike was more than happy to repurpose it. He upgraded the springs to those of an early CJ-5, springs that look the same as a CJ-2A's springs but are longer and allow for a smoother ride, more flex, and a touch more wheelbase. The frame is also boxed at the front framerails, which are then tied to a tube front bumper to help strengthen the frame and provide a mounting point for the Saginaw manual steering box. The C-channel frame is also boxed above the rear spring mounts for strength. The body of the Jeep is a 1947 CJ-2A tub that Mike scavenged from some scrap pile somewhere. The tub sides are full of bondo and rivets, which is fine for this patina'd trail rig. The rear floors were all rusty, so Mike cut them out and replaced them with a large piece of 14-gauge plate steel, which he then Herculined in black. The front floors were replaced using replacement panels from eBay, and the hat channels are made from chopped and repurposed Unistrut galvanized steel.

Vintage Wheels and Vintage-Style Tires

The wheels on Flat-ulence are factory early Jeep 16-inch wheels with inner tubes and bias-ply 7.50-16 Destone Extra Traction tires (that measure out to be nearly 33 inches tall).

The Devil Is in the Details

We could go on and on about the details of this simple and effective flattie, and here's a smattering of more info about the parts on the rig, but we also want to refer you to the many pictures we took of this rig on a recent outing. There are budget hacks and old-school tricks everywhere you look! Check out the door handle and faucet handle on the shifters, the enchilada sauce can cup holder, a dual band VHF/UHF ham radio, Army surplus Mermite for food storage, Big Willy seat cushions and covers, an ammo can under seat glove box, a custom Classic Jeep Tops top, a vintage underdash heater, LED modified 1946 CJ-2A front running lights, a spare tire and Jerry can carrier from Ethel and Murray Enterprises, and so, so much more!