For years, the Jeep 2.5L inline four-cylinder engine returned yeoman service in base model CJ, YJ, and TJs. The little mill, while never a powerhouse, was reliable and produced good low-end torque for its displacement. I had written about a YJ project back in 1995 that I called, "The Little Engine That Could" because it worked so well. Its drawback was its bell housing bolt pattern, which matched the old GM 2.8L V-6. The transmissions that mated to this bolt pattern were sub par in every way. Many aren't aware that in 2003 Jeep changed the engine in low trim model Wranglers to the PowerTech 2.4L double-overhead cam, 16-valve four-cylinder that produced about 30-percent more horsepower and torque than the old 2.5L did. The 2.4L had the 4.0L's bell housing bolt pattern, so the new four-cylinder Wranglers shared the same trannys as their 4.0L siblings. That means stronger, reliable transmissions were available for the four-cylinder TJ.
Dan McKeag, owner of Burnsville Off-Road, and I were talking about the excellent four-cylinder Jeeps we'd owned and he commented he had one with the 2.4L and a 42RLE automatic overdrive transmission sitting in the yard. This was no junkyard dog. It had only 8,900 miles on the odometer and was like new inside and out. This sounded like a project in the making.
It was. Dan had his crew at Burnsville Off-Road go to work and turned this four-cylinder Wrangler into a competent backcountry trail vehicle. Not a budget build, the Wrangler uses some of the very best off-the-shelf parts available today. Check out the photos and see what was done.
Vehicle: Jeep Wrangler TJ
Owner/Hometown: Dan McKeag/Burnsville, MN
Engine: 2.4L dual OHC 16-valve I-4
Transmission: 42RLE four-speed automatic
Transfer case/low range ratio: JB Conversions JK Wrangler NVG241OR Rock-Trac/4:1
Front end: Currie high-pinion 9-inch with HD housing
Rear end: Currie high-pinion 9-inch with HD housing
Ring and Pinion: 5.29 reverse cut
Front Differential: Eaton Detroit Locker
Rear Differential: ARB Air Locker
Suspension: Teraflex Pro LCG with 2.5-inch OME coils
Tires: 305/70R16LT Mickey Thompson MTZ
Wheels/ Backspacing: 16x10 Mickey Thompson Classic II / 4 7/16-inch