I want to do a brake booster upgrade for my 1988 XJ and was wondering what the best route would be in new/remanufactured/used brake boosters intended for a WJ. Would it be best for me to get a brand new brake booster from let's say CarParts.com, RockAuto... or a used booster from the junkyard that's 20 years old?
The price of a brake booster from PickYourPart (my local junkyard) is pretty much the same price as a new one online. I have options below for new parts... if you think the new parts are garbage and the junkyard route is the way to go, let me know.
Brake Booster
Brake Master Cylinder

 

Buy a new one. Rolling the dice on a used part that is 20+ years old is not an upgrade in my opinion.

 

But, you could roll the dice on a new POS also.

 

absolutely true

 

I purchased a 87 Cherokee Laredo about two weeks ago the Booster is leaking but the brakes still works the president of the local Cherokee club has an 88 and told me that he upgraded his booster and master to a 97 it is a direct replacement according to him.

 

 

I've often wondered why we don't see folks using a ZJ booster/master if it's so easy.

 

Here's how I did mine in our '89 XJ. Ours was complicated by the fact that it has the wonderful Bendix 9 ABS. I used a NOS JEEP unit from Omix. It came with the master, booster, spacer and seal, all factory Jeep components.
Note: the bad reviews were mostly people who were trying to screw a standard fitting into a metric hole without the required adapter.