Squeal from rear wheels

un1eash

The way I've rear your post is unless he jack's up the rear leaving it in gear will do diddly squat.
So leaving it in gear won't work unless he jack's up the rear, hence my confusion.

nvingo

No post at this point has mentioned jacking up the rear of the car.
Now jacking up the rear of the car has been mentioned.

But that's not what we're doing, we just want the car to stay where it is, so:

Leaving the car in eg. 5th gear, means the engine will turn slowly compared to road speed, if the handbrake fails, gravity will pull the car downhill and the engine won't offer much resistance.

Leaving the car in 1st or Reverse, the engine will turn fast compared to road speed, if the handbrake fails and gravity pulls the car downhill, the engine will offer most resistance and the car will move slowly if at all.

IronGiant

mjn was reminding people that while working on the car neither the handbrake nor the engine will be providing any braking if the rear wheels are off the ground.  No more no less.    ie it is important to chock the front wheels if you are working on it yourself.

Engaging the engine for normal parking because the handbrake is suspect is a separate issue.

noiseboy72

Most likely worn pads or a seized caliper at that age of car.

If the brake disc looks pitted, scored or has a lot of surface rust, change them as well.

Not expensive to get done and very easy DIY if you have the tools, but if you are not confident, find a good local garage. Doesn't need a main dealer for something this straightforward.