I just started having this problem with my TC rear calipers. Overnight when the temps go below freezing, one of (or maybe both) rear calipers is freezing up and will not release, without driving the car and getting everything warmed up. After driving for five minutes it usually goes back to normal. The calipers are rebuilt and are about 2 years old. I've never had any problems before now. Could this be water in one of the units that is freezing and not letting it release? I tried spraying the cables and levers with WD 40, but it did not seem to help. I remember Eric mentioning that they need to be greased in order for them to work properly. Where do they need to be greased?
The slider pins.
Definitely inspect the slider pins, and the rubber boots around them. You'll probably have to remove the caliper to get to everything. Just grease the hell out of the pins. Also, extend the rubber boots out all the way and make sure there are no holes...that's how water gets in. If you find that you do have holes, there is a kit at NAPA you can get for the TC rear calipers that includes new boots and slider pins.
Go to th parts store and get a spray can of CRC white lithium grease. Stuff some paper towels inside the caliper and around the rotor to keep the grease of them the spray your slider pins. The spray grease penetrates well and will set up as a solid pretty quick. That should free them up til you can get a proper fix.
I took them apart today. It is the cable going to the right caliper. It is seized, and will not move. I have to go to the parts store tomorrow and get a new one. The slider pins were fine. I lubed them up, but the boots were intact and they were not seized. The only thing that bothered me was that, after I sruggled to remove the cable, I was able to move the lever for the parking brake with a pliers, and even though the spring was attached, it would not move it back to an open position. The spring does not seem to be putting any tension on it. I think I may pick up a rebuilt caliper also.
If you get a rebuilt caliper, get one for each side. Last thing you want is a side to side brake imbalange. Especially going into winter in NY.
and the lines that go to the caliper.
Its been my experience that if a caliper is not releasing properly, its because of the crimp where the rubber line transitions into the metal crip at the caliper. The rubber lining on the interior of the hose starts to become cut and fraid (although you cant see it inside the hose) and this blocks fluid from returning to the resivoir when you let off the brakes. Fluid travels just fine to extend the caliper, it just does not bleed back properly. This keeps the caliper partially enguaged and warms up the rotor which warps it as well.
The rubber lines are only a couple of years old. I replaced the calipers, rubber lines, and the cables when I put the rear in the car. I am unsure why the cable seized. The caliper works properly, its the parking brake part of it that does not spring back when released.