Not sure if you know this already, but a brake hose can look fine from the outside but be collapsing on the inside. Then the caliper piston(s) won't release eventually causing the caliper to seize.

In case you need it, here is some good info from the 700/900 FAQ on testing a brake hose. I will be doing the same test myself soon enough!

"Brake Hose Deterioration and Brake Binding. [Query] My front brakes are dragging - both sides and quite severe. On the right side the pads are worn evenly and the pistons move freely. How can I check the brake line for internal swelling/collapsing? [Tip from Herb Goltz] An old brake hose acting like a one-way valve is a very common problem. The inside of the hose rubber deteriorates, creating a flap internally that blocks the return of fluid when the brake pedal is released, causing dragging brakes, warped rotors, and pad wear. Many "dragging" calipers get replaced for this reason. [John Randstrom] The easiest way to check for a bad brake hose is to pump and release the brake pedal, then open the bleeder screws on the caliper. If pressurized fluid escapes the hose is bad. I have had quite a few hoses that were bad that caused a caliper to drag. [Colin] Apply the brake a few times to get the brakes binding and then slacken the bleed nipples. If you get a spurt of fluid and the brake frees off you have a restriction preventing fluid returning back to the master cyl resevoir. This could be brake lines or master cyl. Do the same again but slacken the lines at the master cyl. this time, instead of the bleed nipples. If both brakes are binding equally it`s more likely to be a cylinder problem."

G'luck!

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90 244DL 252K - original engine/drivetrain :)