Starting A Dynasty
In 1986, AMC debuted a radical departure from the CJ. The company was going for a new look to accompany this new Jeep that did everything better than the old one. It was more comfortable on- and off-road, it flexed better (once you pulled the sway bar and track bars), and it had a quieter, more reliable, easier-to-use transfer case. The Wrangler got a better frame, wider springs, and better rust-proofing than the '86 CJ did. The soft top sealed better, the wipers actually worked well in snow, and the defroster defrosted more than two triangles of the windshield.
That said, it is almost as if AMC didn't want it to succeed. The company killed the long-storied "CJ" family lineage in favor of things like "YJ" and "Wrangler." It got rid of the iconic round headlights in favor of rectangles, the Jeep was lower to the ground, and in place of a simple steel dash was a plastic-covered thing that everyone was convinced was going to rattle and squeak within a year. Then Big Brother threw a monkey wrench into things with CAFE and emissions standards, which translated into a TBI-injected four-cylinder that, if something went wrong, was not easy to fix. The computer-controlled carburetor on the 4.2L engine (that featured more linear feet of vacuum line than many parts stores even have in stock )was a feeble attempt to meet government regulations.
To this day, the YJ Wrangler still carries a stigma, and it isn't as popular as the CJ that preceded it or the TJ that came after it. It is still a great Jeep and a good platform to start off with, and because most other people are looking at CJs or TJs, it often means you can score the Jeep that started the twenty-plus years of the Wrangler's reign as the best off-road production vehicle for half the price of a similar condition CJ or TJ. So follow along and we'll give you a crash course in what to look for in a YJ Wrangler.
'87
The '87 Wrangler was an odd bird. It got steel half doors, but no locks on them. It got windshield-mounted mirrors that were different than the CJ's, but only lasted a year. It was the only year the top used snaps at the steel door, so unless you convert, you can't use tops from other years. The 4.2L was bulletproof, but it was bolted to the Peugot BA 10/5, which was a waste of good alloy. It was also saddled with a computer-controlled Carter carburetor, which many times did not run well when it initially left the factory. The 2.5L got a throttle-body injection system and was bolted to the AX-5 transmission. No matter which engine you opt for, you'll end up with the internal hydraulic slave cylinder. It can be problematic, and when it goes out, you need to pull the transmission and T-case to get to it. Then Jeep threw an NP207 into the mix, again the only year for that T-case to grace a Wrangler. Basically, the '87 YJ is only a bargain if you are planning on replacing the drivetrain anyway.
'88-'90
Things got a bit more uniform after that initial year was over. All the bodies were galvanized, most of the steel half doors got door locks, the soft tops were the same as the later years, and mirrors were moved to the doors for both the half-door and full-door Jeeps. Both the carbureted six-cylinder and the TBI four-cylinder received the NP231 T-case, which were around until the end of YJ production. During the '89 model year, as with the Cherokee, we started to see the AX-15 installed in order to get rid of the Peugot transmission.
There are many more fans of...
There are many more fans of the 4.0L than the 4.2L, thanks to its out-of-the-box reliability. However, if you swap the carburetor out for a fuel injection kit, such as the Mopar unit on this 4.2L, it makes a world of difference. The 4.2L pulls harder right at idle when you let off the clutch than the 4.0L does, and while it doesn't pull as hard at the top end, if wheeling is your main concern, maybe a 4.2L Jeep without the computer-controlled Carter carb is what you need.
If you look at the back of...
If you look at the back of the bellhousing, on the driver's side, and see two lines coming out of it, you've got the internal hydraulic throwout bearing. When it left the factory it could go for tens of thousands of miles without a problem. Once it does go, it is often a frequent problem and many YJ owners, after a few internal hydraulic throwout bearing replacements, bolt-on the parts from an external-slave transmission to fix it.
If your potential YJ has been...
If your potential YJ has been ridden hard, you might find some frame cracking around the steering box mount, or the frame-side track bar mount. Thanks to many hundred-thousand miles, and a rough rustbelt life, this track bar managed to separate the frame completely. In the south, you will only see this if your Jeep has been flogged really hard, or if it came down from the north. Regardless of where you are, take a quick look at it before you buy.