Does this look like sticking caliper or something else?
 

This is on my 1987 260E...

I have this high pitch squeak while driving from the right side and also the car pulls very slightly to the right.

Here are some hard readings though with my IR temp gun on each wheel:

FR Wheel: 128F
FR Caliper: 151F
FR Disk: 167F

FL Wheel: 110F
FL Caliper: 131F
FL Disk: 131F

As you can see the right side is much warmer for sure.

You guys think its a sticking caliper or could there be anything else causing this noise?

The pads looked okay and I couldn't tell if one was worn more than the other. They are brand new rotors + pads from last year. The caliper is from a 400E I got from the junkyard (4pot).

I don't think those temps are anything for brakes and certainly not suggestive of any drag. If one was say 350 then maybe a concern.

What about the bearings maybe causing the squeak?

Well that was after leaving the car off for 15mins while I went inside to find the gun...

Bearings are possibility, but I have no slack up/down when I grab the wheel. Should I maybe replace them and get them repacked for good measure?

When was the last time the brake fluid was changed? Jack the front end up and spin each front wheel to see if you can feel a difference. You don't need to replace the front wheel bearings if they are ok but you will want to replace the hub seal.

Changed brake fluid with ATE Blue last year with the brake upgrade using motive power bleeder.

I'll try spinning each wheel and report back.

My reason for doubting any drag is I have a motorhome that I've had some brake problems in the past (big problem, but that's another story for another forum ;)). Now the MB isn't a motorhome I understand but from my experience a dragging brake that is a problem is going to be several hundred degrees F (350, 400 maybe even higher), not just the slightly elevated temps you metioned. Also when i had my issue, i became very astute to my temps on all my vehicles and it isn't uncommon for them to be well into the range you mentioned or even up to 200 and a bit above if you have done some repeated or heavy braking before checking. Just my thoughts and probably only worth what you paid for them!

Regarding the wheel bearings, if they haven't been packed recently that is an easy job and worth doing anyway. I would not replace them, no reason for that unless you get in there and find some obvious worn bearings. You will need new inner seals but those are only a few bucks each. I recently packed the fronts on both of my W124's since they needed adjusting (tightening) anyway. It may not be the problem, but its a good routine maintenance task that probably is seldom done but an real easy job and worth a couple hours. Sounds like after that you will have eliminated all the potential problems with the front wheel making the noise. Good luck, these things are fun to do anyway.

Any chance it isn't coming from the wheel and it's an idler bearing or something? I am not familiar with the 87 260E but I know on the mid 90's gassers (E320) the smog pump pulley and tensioner pulley (idler) can wear out. I assume your car has some of that kind of thing that could cause the noise, maybe only when revving it up when driving? Again more free advice that is probably worthless.

ps2cho, a brake hose deteriorating on the inside can prevent a caliper from releasing properly, causing its brake pads to drag slightly.

^2, it acts almost like a check valve.

Def not that as I replaced the front brake hoses too haha :)
They were cracked on outside so replaced them.

View video:
Sticking caliper? - YouTube

You can see something is definitely going on...

Does this give a better indication? I want to repack the bearings, but with my wagon out of action with the transmission, if something goes wrong I cannot afford to be stranded right now....so any more thoughts based on the video?

Agree, right is dragging. To verify if pads vs bearings, push the pads back manually (eg with lever, opening bleed screw if needed) and retest.

W/O watching the video, a question, does it pull all the time or just when braking? If it does it all the time, does it pull any worse when braking?
Gilly

Have you pulled that right wheel and tried to tell if it's the brake/rotor or bearing (meaning you can put your ear right down on the sound or clearly see it when the rim/wheel are removed)? If you still are unsure, you can easily pull the caliper or pads. If it's still making noise, bearings are all that's left. At some point the rubbing better stop! I recently replaced the rotors/pads on my 95 E320 and when done I had a brake rub sound. I ultimately found that tightening the wheel bearings was the fix (although I packed them as part of the process).