Rear brakes...what a mess

[Bad Lobster]

I recently posted on the "new member" forum that I'm new to Saabs but bought a '96 900 on eBay. I had a mechanic look it over and one thing they told me was that the rear brakes would need work within the next few thousand miles. Well, several weeks later I went in to put in new pads and...

The pads were worn but not horribly so. I already had the new ones, so I replaced them. More worryingly, the surfaces of both pads and rotor were a bit rusty. The non-friction surfaces of the rotors had very heavy rust (East Coast car) as did the pins that hold the pads. The parking brake shoes have very thin linings and also have surface rust. On the bright side, the bleed valves were fine and I backed off the calipers and put the new pads in. Oh, and one more thing: the set screws (the ones that prevent the brake rotor from turning relative to the hub) were missingon both sides. Is this really a problem? It seems to me that the lug nuts should hold the rotor in place with or without set screws.

I also adjusted the parking brake star screws--it's been a long time since I had a car that wasn't self-adjusting, and I never seem to get these adjusted very well. I also had Mrs. Lobster step on the brake pedal while I sat by the back wheel and watched the caliper. I didn't see any movement at all.

The bottom line is: brake pads and rotors should be shiny on a car that's been driven several thousand miles in recent months. I suspect the rear brakes aren't working at all. You'd think I would have noticed this while driving, but who knows?

Now the shaggy dog story is over and I get to my question for the forum. It looks like I might need to get my rear brake calipers and cylinders rebuilt, parking brake shoes relined, and the rotors machined or replaced. (Also those little pins that were so rusty.) Are all these parts available, and how much is it all gonna cost me? How much is it gonna cost if I take it to a mechanic instead of doing it mself?

[Bad Lobster]

Followup: I put it back together with the new pads but nothing else changed and yeah, braking is pretty weak. It's surprising how easy it is not to notice poor brake action in a car with power brakes, as long as it still does stop eventually. No one else who has driven the car niticed either, including the mechanic who did the pre-purchase inspection.

[Oscuro]

All the parts are quite available and the work is DIYable. RockAuto has a good selection of all the bits (rotors, pads, hardware kits, handbrake shoes, etc.) and always has 5% off coupon codes floating around, but shop around too. I don't think it's worth resurfacing the rotors or relining the shoes, since replacements are not very expensive. Rebuild kits are available for the calipers to replace seals and other wear items, but not everyone is comfortable doing that and may opt for remanufactured units.

The set screws are optional and I wouldn't worry about replacing them. Rust on the non-friction surfaces is pretty unavoidable too in a damp/salty area.

[Bartman]

Your rear calipers are rusted and the pistons are not moving properly. That's why the rotors are rusty. You need to rebuild them or replace them. Replacements are inexpensive from Rock auto.

The most difficult part will be getting the flare nuts that hold the metal lines into the calipers unscrewed without breaking the lines. I suggest spraying the flare nut threads with PB Blast for several days. Get a flare nut wrench, fit it carefully, then try to break them free. If they move just a smidge, tighten again, then loosen again just a smidge. Continue that, loosening a little more each time, until they are loose on the lines and they are coming out. If the lines break , twist, or are rusty, you will need to source some from a junkyard or get the proper flare tools and fittings to make some up.

[Bad Lobster]

Thanks - I took the car to a Saab shop to have it evaluated. The mechanic test drove it and said the brake action was just fine; maybe I was talking myself into seeing problems that didn't exist. He said that as long as I was able to push the pistons back into the calipers to get the new pads in, the calipers are OK (and he's never had to totally replace a caliper in one of these cars).

As for that flare nut on the brake line, that was one reason I wanted to avoid this job if possible. I bought a flare nut wrench just for this job, and promptly rounded off the corners. I don't want to mess with it any more and risk breaking it, so I'll leave it alone as long as I can. (btw, it IS possible to remove the caliper far enough to get the rotor out without disconnecting the brake line, as long as I don't let it dangle. Even though the brake line doesn't have a flexible hose, the metal line has a little bit of give.)

Case closed. Thanks for the input, everyone.