The first Wrangler was introduced amid tighter CAFÉ regulations, tighteremissions laws, a fear of the new computer-controlled engines, and a recent witch hunt that killed the CJ-5. It was a Jeep of many compromises to many groups and some will argue that it met none of the pundit's demands well.
We can remember being down on the new Jeep, too. "No more CJ?"; "What is with those headlights?"; "I can't fit a 31-32-inch tire anymore?"; "Where did the tailgate go?"; "What is with this plastic junk for a dashboard?" Yeah, we were as angry as everyone else.
It didn't take us long to come around and now we see how much of an improvement the Wrangler was over the CJ that preceded it. With a better frame, a galvanized body, wider and longer springs, the big picture was really nice, even if none of us could see the forest for the trees. After a few rough years, the YJ really hit its stride and the Wrangler ran with the same basic powertrain for 15 years.
Much of the Jeep community has come around too, but not before the TJ popped up and eclipsed the YJ. The buy-in price for this cornerstone of the Wrangler marque is low and there is a lot of value, but like any other vehicle, there is just a bit of caveat emptor. So sit back, strap in, and run with us as we run down 10 of the most common chinks in the YJ armor.
The Central Axle Disconnect system or CAD was a response to two separate inputs. On the one hand, Jeep had to meet better fuel economy goals, and on the other hand, Jeep was looking at a consumer who was sick of locking and unlocking hubs. Who wanted to get out of the Jeep when the going got rough?
Sounds nice, doesn't it? Better mileage and no need to get out of the Jeep to engage 4WD must be a great idea. The issue is, the CAD system straddled the crossroads of the dawn of the chain-driven T-case and a change in the demographic of the typical Jeep buyer. It was a system that was outdated as soon as it was introduced. A chain-driven T-case by nature can absorb more shock than a gear-driven case, spinning the planetary doesn't suck up that much fuel, and the CAD really wasn't needed. However, for 46 years there were manual hubs to disengage the front axle, so some disconnect must still be needed, right?
The problem is that the system relies on vacuum and electric for everything to work. Dried out lines or melted connectors means something has gone wrong with it. Most often you will be stuck where you should have been able to drive out of.
Getting rid of the system is the best way to fix it. Hand-me-down TJ or XJ axleshafts will work, but you'll have to pop the carrier out to install a new inner axleshaft seal. The easiest way to get around the troublesome system is to install a 4x4 Posi-lok that replaces the vacuum portion with a cable that you engage from your seat. If you are an abusive driver, however, the cast CAD portion is prone to cracking and leaking. You can use an XJ front high-pinion axle, cut off the XJ brackets, weld on leaf spring mounts, and swap your gears, outer knuckles, unit bearings, and brakes over.
Flatter, more supple springs made for more lateral and vertical movement than the old CJ springs ever had. The flatter springs necessitated a sway bar, and a track bar was added front and rear. Both items became standard for the entire Wrangler line.
The problem with the track bar is that it moves in an arc, while the leaf springs want to move straight up and down. The dissimilar movement puts unneeded stress on the frame and axle. Over time, we've seen brackets tear off the frame and even break the frame. Ditch the track bars and never look back.