I'm going to disagree with this, in my experience. A rear disk upgrade is a nice step up from drums especially if you carry a load or pull a trailer that puts the weight square over the rear axle.
Vanco/WJ upgrades are excellent choices too. And so are the Black Magic/Centric Premium rotors if stock sized stuff is kept.
Not much disagreement here. I mostly like the ZJ discs. They are more powerful than the stock drums, which is good when loaded but more prone to lockup, when empty. ZJs have rear anti-lock brakes which controls the lockup problem, when stock. I need to install a adjustable proportioning valve to limit the rear when empty.
One thing I do dislike about the ZJ discs is the weakness of the parking brake. The drum is much smaller than the stock brakes and just doesn't have much power, even with all new parts, properly fitted.
My point was the front brakes are the ones in most need of improvement.
Changing to ZJ discs did not give much of a seat-of-the-pants sensation of more powerful brakes, not like when adding the Vancos.
The Vancos are a good addition, powerful enougth to lockup 33"s on pavement, at freeway speeds.
Later upgraded to the bigger Sport-Trac calipers and Black Magic pads, it now stops even better but the rear, when empty, lifts more, leading to earlier lock-up. The ZJ proportioning valve doesn't appear to be calibrated for the more powerful front brakes.
Like I said before, I need an adjustable proportioning valve.
