Both cylinders are leaking on one side. Can they be replaced without removing the backing plate? Youtube has a few videos but nothing definitive. Thanks!

 

The cylinders are accessed by removing the drum. You do not have to remove the backing plate, although I have seen folks mention buying "loaded" backing plates for trucks like this.

You need a shop manual that spells out the brakes. The spring in the parking brake is dangerous if you don't know what you are doing.

 

I'll have the spring caged on the side I'm working on but I also agree, I definitely need a shop manual, videos are nice, but just don't give all pertinent info needed. Also have a Girling adjusting tool and spring tool on order.

 

How much? And where did you order these special "girling" brake tools from? I'm actually getting a truck going that has these brakes, but havnt had any issues with brakes yet besides the res being somewhat low of dot 3 fluid. I havnt drove it enough to notice any leaking anywhere but to my knowledge the previous owner could have done something with brakes and just finished bleeding system and forgot to top it off, so that could be why its low but I did drive it home about 100miles and didn't have any brake issues on the way but the carb that was on it that's another story.....

 

Brake Spring tool: https://smile.amazon.com/OTC-7462-Gi...-no-redirect=1

Adjustment tool: https://smile.amazon.com/OTC-5072-Lu...E2CDX3G8MBYD7S

 

Thanks for the info. hope all goes well for your project your working on....

 

To give an update, both sides got to leaking really bad AND one of the Maxibrake chambers had a broken caging bolt. I decided to go with loaded backing plates and new Maxibrake chambers for both sides. The only brake components I reused was the shoes.
You will need the Lucas Girling adjustment tool - it is a must! I was able to adjust the top and bottom shoes with no problems whatsoever, I've read where people say the leaf spring is in the way to adjust the top shoe even with the tool, but I had no problem. FYI, the 'Arrow' stamped in the backing plate is the way the handle needs to be pushed on the tool, not the way the adjustment wheel needs to be turned I had also purchased the spring tool but I didn't need it. I think it is needed when replacing the shoes without pulling the hubs. I would recommend having an inverted flare kit on hand as one of the lines refused to allow the flare nut to turn. After multiple penetrant oil soaking/heating/soaking cycles I decided to cut the line and replace it. Advance Auto had the lines and fittings I needed.
Also to replace with a loaded backing plate I needed a 3-1/2 inch socket for the wheel bearing locknuts. Other tools I used was a really bright LED headlight (helps to see while adjusting shoes) and a large pair of Channellock pliers for the Maxibrake locknuts then just common tools most every backyard shade tree mechanic will have on hand. I also watched some videos on Youtube - very helpful.