Vibration through steering wheel

[abh29]

Folks, its back!
I got out of the car earlier in the week and there was a distinct burning smell from the brake on the rear driver side. I jacked the car up and the wheel wasn't spinning freely at all.
I removed the slider pins and cleaned them up, and I've also adjusted the handbrake to make sure it isn't dragging on the disc internally. The pads are tight in the caliper, but how do I adjust that?
The caliper seems to operate correctly, although the piston does have some corrosion on it and could probably do with a clean.
I'm minded to replace the caliper, but when I rotate the wheel when the car is jacked up, it rotates and there are patches where the disc is clearly rubbing on the pads, and areas where it isn't.
A new caliper is close to £100 and I don't want to replace the caliper unless it is the caliper.
When I got back today, the caliper was red hot, whereas the opposite caliper was cold.
Thoughts?
P

I am surprise at your figure of £100 for a new caliper.
A few month ago after about 35 miles f/o/s pads started sticking resulting in very bad vibration in steering, the wheel was very hot , the n/s/f was hot but not as bad. Called at a mates to put his thermometer on them , can not recall actual temps but very hot decided to change them.
Went and bought 2 Discs,set of Pads[Pagid] and 2 Calipers from ecp at the rates that day totalling £224 [got refund of £48 on return of old calipers]
Unfortunately this was only 4,000miles after replacing all discs and pads.
Turned out I needed to also had to renew two brake hoses as they were also a bit the worse . Got BMW parts to be sure but one did not fit ,resulting mate making a new hose,fortunatly he has all the equipment to do that.
Just hope the rears dont need doing , they are double the price of fronts if I recall the comments at ecp counter correctly

 

[Philpatton]

So I thought I would write a conclusion to this issue as I appear to have sorted it with everyones help, especially t-tony. This morning I stripped the calipers and set about them with a wire brush and sandpaper to remove any corrosion around the areas where the pads sit. There was a significant amount of corrosion which came away quite easily. At this point I copper greased all the metal on metal parts and when out for a jolly drive, fully believing that the issue was resolved, however it wasn't. After i returned from my jolly out, the caliper was red hot again and I had pretty much resolved myself to paying a pro to sort it out. Grrrr
After a cuppa, I read the comments from Tony who advised that it may be worth exercising the piston with some WD-40 to see if that cleared the issue. It was here that my day started to get better. The rubber boot around the piston had come away for a length of around 5-6mm which would have let any water in, and maybe even prevent the piston from slightly retracting. Lots of squirts of WD-40 and exercising the piston and replacing the rubber boot in the square rebate (which is a pig of a job), the issue appears to be resolved.
Moral of the story is tackle each piece of the puzzle one at a time and don't lose faith!
P

 

[gookah]

I am surprise at your figure of £100 for a new caliper.
....
Just hope the rears dont need doing , they are double the price of fronts if I recall the comments at ecp counter correctly

Rear callipers are far more expensive than the fronts for some reason, and his problem is rear