2007 Jeep Wrangler Unlimited Rubicon - BluePosted in Features on March 1, 2009 Comment (0)
Saying a JK is "old" sounds strange, as they've only been available since mid 2006. But that's two years, and two years in the Jeep world can be a long time if a vehicle is ridden hard and put away wet. We got our hands on a 2007 Jeep JK Wrangler Unlimited Rubicon that had been one of the very first off the assembly line in 2006. This JK had seen 31,000 miles of tough use and little maintenance. For example, when we pulled the crankcase drain plug, black liquid came out that looked more like tar than oil. There was sludge in the oil pan. It was time for a project!
While this JK was a Rubicon, we decided that we wanted to run 40-inch tires on it, so the stock axles probably wouldn't hold up. We contacted Dynatrac and ordered a pair of Pro Rock 60s with 5.38 gears and Eaton Detroit Lockers. The Pro Rocks will hold up to anything we plan on doing with the JK. While the front and rearends were being built, we made plans for the rest of the Jeep.
The hard top had a hole in it, so it needed to be repaired. The paint was OK, but needed some touching up. The sludge-filled 3.8L V-6 was problematic. When was the last time the oil had been changed? Had the JK been thrashed and not maintained at all? We decided to change everything.
Dan McKeag and the staff at Burnsville Off-Road in Burnsville, Minnesota, had built two Hemi projects for us in the past that worked perfectly with no issues. Their JK V-8 conversions look as if they came from the factory. Burnsville started as a body shop, so Dan's staff also do paint and bodywork. Obviously, they would be the perfect shop to build our JK. After talking with Dan, it was agreed that Burnsville would perform our JK makeover.
We had built a project YJ in Off-Road Magazine that was painted Ford Grabber Blue. We really liked the way that Jeep looked, so we told Dan and crew to paint the JK Grabber Blue, too. They went to work stripping the JK down, as the inner door panels and many other pieces needed to be painted. Before the JK had the black armor and top reinstalled, the staff at Burnsville was calling our JK "Smurf." After everything was bolted on, they grudgingly admitted that it looked great. Burnsville also repaired the top to factory specs.
By the time the Jeep was out of the paint shop, the Dynatrac Pro Rock 60s had arrived. Dan does some work with Mopar Performance, so he suggested we try the new Mopar/Rubicon JK suspension. While this kit is basically a Rubicon Express long-arm suspension system, some things are changed, such as track bar mounting and shock valving. We gave him the go-ahead and the Pro Rock 60s and Mopar/Rubicon suspension were installed under the JK. Both the Pro Rock 60s and the Mopar suspension were built for JK Wranglers and were installed with no issues.
At the time this JK was being built, Burnsville had a number of brand new takeout 3.8L V-6 mills sitting in storage. We decided to install one of these into our old/new JK and replace the worn-out 3.8L. This was fine, until Dan reported that he had driven the Unlimited with 40-inch (39.5) Iroks and said that it worked great in low range, but highway performance was sad, even with the 5.38 gears in the Dynatrac 60s. It looked like a Hemi was in our JK's future.
We decided that a 5.7L Hemi with 545RLE five-speed automatic would wake things up. A 6.1L Hemi intake was installed on the 5.7L, giving us about 25 more horsepower than the stock 5.7L produces. The 545RLE mates up to the Rubicon RockTrac transfer case, so no adapter was required. Burnsville uses its own aluminum radiator and an AEV harness, so everything looks and works as Burnsville swaps always do - like OE.
For armor, we chose to use front and rear bumpers from Hanson Offroad. The stubby front bumper has factory foglight mounting points and makes a great base for the Warn 9500 HP PowerPlant winch. The Hanson rear bumper is cut high and angled for a better departure angle. Kevin Hawkins fabricated the body-mount spare carrier, but we've found mounting a spare there isn't a great idea, unless you want to have a bent door when you make a steep climb that catches the spare. Stock JK Rubicon rocker guards were retained for now, although we expect they'll be destroyed by the next installment. To run the 39.5-inch Iroks with no rubbing, Burnsville trimmed sheetmetal in the rear fenderwells and installed a set of Xenon flat panel flares at all four corners. The big tires don't rub at all, even when fully stuffed into the wheel well.
Inside, we had Burnsville install an upgraded OE head unit that receives Sirius Satellite Radio. We also installed a Jeep Trail Guide GPS. A Tuffy Security center console insert secures small items and gives us a comfortable armrest. Mopar Accessory slush mats protect the carpet. Other than those changes, the interior was left as-is.
Burnsville installed a PSC hydraulic ram-assist steering system. In some of the photos, you'll see the ram underneath the OE tie rod. Once they received the material to build an aluminum 7075 tie rod, we had Mount Logan Off-Road exchange the stock Rubicon tie rod with a beefy 7075 aluminum tie rod. This necessitated changing the ram mounting points. We took this opportunity to move the ram above the tie rod by using a Currie Enterprises track bar bracket that moves it up out of the way and allowed us to get rid of the track bar drop bracket on the frame.
Blue really works. What's surprising is that it works so well as an all-around Jeep. Highway performance is superb. The Mopar-spec Bilstein shocks are valved perfectly for the road. Off-road, the 39.5-inch Iroks work as they always do and get us through just about everything. The Pro Rock 60's ground clearance is amazing. You know how it is; you see the big rock coming too late and just know that it's going to whack the diff. With the Pro Rocks, we've cringed a number of times and never hit anything! The Hemi is a big improvement over the 3.8L V-6. The 3.8L works okay with tires up to 37 inches as long as you gear the Jeep down. Larger than 37s, you need to look for more horsepower and torque. We'll be driving this JK to most events and trail rides, so look for it in the backcountry. You can see how an "old" JK can be made better than new.
The front Dynatrac Pro Rock 60 has the new Pro Stub-Hub locking hubs, 5.38 gears and an Eaton Detroit Locker. The Pro Rocks are built for the JK Wrangler and have tone rings and everything else necessary to keep the JK's ESP, ABS, and other systems working. They also work with the OE JK tie rod, drag link, and track bar. We used the stronger Mopar/Rubicon drag link and track bar, but kept the factory tie rod. The OE tie rod wasn't in keeping with our bigger-is-better theme, though, so Mount Logan Off-Road installed a strong 7075 aluminum tie rod. When they did this, they moved the PSC ram up above the tie rod to get it out of harm's way. To do this, they used a Currie track bar bracket, which raises the mounting point 3 inches above the axle housing. This also allowed us to get rid of the track bar drop bracket on the frame. All JK Wranglers have an issue, though. The track bar and drag link aren't the same length and don't describe the same arc as they travel up and down, even when they're the same angle. The factory can get away with this because there's not much travel in OE trim. By increasing suspension lift and travel, we make things worse. We plan on working on this issue in the future.
39.5x13.50-17 Interco Irok bias ply tires are mounted on 17x10 Raceline RT-Monster cast beadlock wheels. The Iroks work great everywhere, but superbly in mud and snow conditions. Bias ply tires work better off-road. Don't argue with us about that. The new Raceline Monster beadlock wheels use the latest pressure casting technology. Since they start as beadlocks, there's no welded ring. The 32 bolts and steel ring that sits flat on the rim ensure there will be no beadlock failures. The Monster beadlocks also feature a thicker and stronger inner bead. While their specs say they're a 17x9.5 wheel, they really measure 17x10 with a 4-inch backspace. This is fine with us. Note the valve stem placement. It's in the spoke area where it's easy for us to access, yet hard for rocks to damage. The Dynatrac Pro 60 Stub-Hub is 2.388 inches shorter per side than a stock Dana 60 hub. Using the strong and reliable Stub-Hub makes your front end over 4.5 inches narrower! An added benefit is they won't be hit by every rock we scrape by.
The rear Dynatrac JK Pro Rock 60 has 5.38 gears and an Eaton Detroit Locker. Like the front, it comes ready to plug into the JK so everything works as stock. The Pro Rock 60 has more ground clearance than a Dana 44! The Mopar/Rubicon Bilstein shocks are valved perfectly for on-highway and normal off-road use. If you drive fast and jump the Jeep sometimes, the shocks could use more damping. The Mopar suspension system differs here from its Rubicon Express sibling by putting a raised track bar bracket on the axle, instead of using a drop bracket from the frame. We still think all aftermarket track bars should be adjustable. This one isn't, but Rubicon Express and Mopar should have an adjustable rear track bar available by the time you read this.