A buddy of ours that works for Jeep used to joke about the vehicles falling apart at 75,000 miles. We've also heard complaints about Jeep quality in the past. Much of it can be dismissed as owners not understanding it's a Jeep, not a car. Jeeps have some inherent audible noises and quirks. Anyway, we decided to keep track of the reliability our '01 Project TJ. And not only did we keep track of what went wrong with the factory parts, we kept an eye on the aftermarket ones as well.
We introduced Project Red in the January '02 issue ("Road Trip With Red, Part I") and built it up issue by issue until the March '03 issue ("Road Trip With Red, Part VIII"). Since then, we've put a total of 115,000 on- and off-road miles on Red, so we know what worked and what didn't. With 4 inches of lift and 35-inch tires, Red is a typically built TJ. Even though we've been slackers in the maintenance department, our TJ has held up pretty well. Oil changes and grease-gun intervals ranged from every 3,000-7,000 miles, but the tranny is still on its original oil. The front differential lube has nearly 100,000 miles on it and we're sure it needs to be changed, but the rear diff and the transfer case have actually seen a few oil changes. Ultimately, driving over the equipment's capability and abuse could have caused a lot more damage to our Jeep than our lack of maintenance, but here's the lowdown on what went wrong and right on Red.
30,000 Miles
Final story on Project Red goes to print. Rear Dana 44 ARB Air Locker has internal seal failure (inside differential, not installer error). We replaced it with a Detroit Electrac.
32,000 Miles
Rear passenger-side axle seal begins to leak. Pull shaft and silicone the outside of the seal surface to the housing. Leak fixed.
65,000 Miles
Installed a high-clearance skidplate and replaced the 4-inch lift coils with 3-inch. The rear driveshaft angle looks fine
77,000 Miles
Currie rear driveshaft begins making noise after a 1,700-mile road trip to Colorado at 75-plus mph in 100-plus degree heat. It turns out to be a wasted CV (looks blued and overheated). Replace with another Currie driveshaft (CE-97984).
83,000 Miles
HVAC fan quits working. Starts out as an inconsistent problem, but eventually stops working entirely. Heat and A/C still work, just no fan. Try replacing parts that Web wheelers recommend ($80 fan switch and heater resistor), and it doesn't fix the problem
85,000 Miles
Original front brakes finally wear out. Driver side is worn down to the metal. Installed new rotors and pads. Rear brakes have more than 50 percent remaining
87,000 Miles
Second wasted CV rear driveshaft. Replaced it with same Currie part number again and removed the high-clearance skidplate that was causing too much angularity. The Currie driveshaft has greaseable U-joints, but the CV is a sealed joint. A regularly lubed, greaseable unit would probably survive with a high-clearance skidplate and 3-4 inches of lift. Rear output seal on Currie slip-yoke eliminator kit leaking. Replace special Currie-only seal (CE-9069TS).
90,000 Miles
Rear Dana 44 Detroit Electrac not functioning properly and is making noises. Seems fine with the unit unlocked. We hardly need the locker anyway because the limited slip works well.95,000 MilesRear Detroit Electrac begins to bang and clunk, even when unlocked. Pull it to find it has eaten itself alive. Replace Electrac with the new version of Detroit Truetrac limited slip (new 50 percent stronger three-pinion design).
105,000 Miles
Summertime temps get out of control, so we focus on fixing the HVAC fan. Pull dash apart to find it's the HVAC switch itself. It looks slightly overheated and melted. Pull apart, clean, and lubricate switch. Air conditioning and heater fan works again!
110,000 Miles
Avenger Supercharger reaches 100,000-mile mark and begins to whine. Sounds like a bearing noise near the rear of the unit. Rear output seal on transfer case slip-yoke kit leaking again. Replace special Currie seal again (CE-9069TS).
115,000 MilesRadiator looking scaly inside and Jeep seems to run hot even though the gauge says it's OK at 215 degrees. Install flush-and-fill adapter in heater hose, flush out the system, and refill with fresh coolant. Still seems like it's running hot even though the gauge reads 210-215 degrees (normal)