I noticed my rear brakes were getting quite a bit hotter than the fronts. I took off the rear calipers and discovered one was stuck, driver's side rear so I replaced both. Now that side seems normal but the passenger side rear is hot enough to sizzle water while the other three are just warm.

I replaced the brake hoses at the corners and all the calipers, pads and rotors four years/40k miles ago. I didn't replace the two center rear hoses though.

I'm wondering if this is more likely to be the center hoses collapsing or the MC, booster accumulator assembly. There are no lights on the dash. Could the system be preventing the brake fluid from returning on one side only? And would there be a warning light if it's the MC?

I'll probably go ahead and replace the center hoses, as that's probably the last possible fix I'd want to do myself, but I was hoping to see if someone had some advice. Thanks in advance.