I know the ZEP works but also check the slide cables if you hear a 'jingling' noise or squeal. The cable, chain and rollers do not use any lube. The BAL website and instruction manual will give you what kind of cable slack is acceptable. Adjustment as a DIYer is very easy though the first couple will put you on a steep learning curve and may take an hour or so. You need 3 tools - a 3/8" and a 7/16" wrench and a pair of pliers or , better, Vise Grips. The wrenches I use are the ratcheting GearWrenches
You most likely do not have rollers under any slide as Keystone started using a slide bar instead, evidently as a cost reduction. Ours has rollers under the bedroom side only with the other three slides having the slide bars. A note about those slide bars - they occasionally do collapse/fail though I believe that has been corrected after 2015.
Add on rollers are often the LCI J-36 service rollers. They are a bit taller then the slide bars. I have a box full of them but have been reluctant to give them a try with that extra 3/8-1/2 inch height.
ZEP lube may be great stuff but way over priced. I found CRC industrial power lube with PTFE has the same basic ingredients and a bunch less money and works very well on our 3 rollerless slides:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1