1986 MGM 5.0.......opinion needed

[Toploader]

When I replace the rear shoes should I just re-build the wheel cylinders, or just put in brand new units?

Additionally, if it is found that the rear cylinders are dry and not leaking, should I just leave them be, or rebuild/replace?

[friskyfrankie]

May depend how long they have been in there. If a "long" time (which you need to determine the definition of) I would replace them as they are cheap enough. As long as you don't screw up the brake lines (possible if they are very old) "no harm, no foul".

[Toploader]

May depend how long they have been in there. If a "long" time (which you need to determine the definition of) I would replace them as they are cheap enough. As long as you don't screw up the brake lines (possible if they are very old) "no harm, no foul".

Yes!........two weeks ago I had to replace the rear drivers side brake line........rotted out with numerous tiny holes;-(

[gadget73]

at a minimum peel back the dust boots and check for wetness and verify both pistons move freely. If it moves properly and isn't leaking, leave it be but don't be too surprised if they need to be replaced. Could always order them and the hardware just to have on hand. Only need what you don't have.

[friskyfrankie]

Do check all of the other hardware especially the rubber (or whatever they may be using) brake hoses. They may "look" fine but deteriorate from the inside by clogging up (like a person's artery and stop brake fluid from traveling to the brake and back).

[Toploader]

at a minimum peel back the dust boots and check for wetness and verify both pistons move freely. If it moves properly and isn't leaking, leave it be but don't be too surprised if they need to be replaced. Could always order them and the hardware just to have on hand. Only need what you don't have.

This would be what I will most likely do, as long as I am in there replace everything. Rock Auto is cheap enough!

[DerekTheGreat]

Replace them. I left the ones on a 1992 C1500 when I did the rear brakes because they seemed OK when I peeled back the skirts. A few weeks later one piston seized up after a hard stop, taking the backing plate out with it. Your results may vary.