parking brake, rear pads

This may be due to the fact that there is one leading and one trailing brake shoe in the system. The leading shoe gets worn and bedded in much quicker because of the normal forward direction of ware and thus beds in quickly. the trailing shoe rarely sees much movement in reverse so does not bed in as well.

John (Britprius)

 

Thanks for the explanation BP. So just wondering, have you ever noticed any asymmetry between the forward and reverse effectiveness of the park brake on your Prius?

 

If I were you I would replace the discs and pads at the same time if possible.

The problem with just changing the pads (after freeing the slide pins) is that the new pads will ware to the shape of the old discs. However you could continue the old discs as the brake performance will be no worse than it is now. This is assuming you do not do a 1000 miles a week, but some reasonable figure.

Your discs look about the same as mine when I replaced them at about 80,000 miles.

When you replace the discs the new used pads would not bed in for a long time, because they will not be flat. This will cause the new discs to rust where the pads do not contact the new flat discs.

You could fit another new set of pads, but these are about £30 so could be as much if not more than new discs. The alternative would be to rub the new "used pads" flat on some sand paper before refitting.

You will probably find when you remove the discs the back of them "the side you cannot see" will be worse than the side you can see.

Hope this helps.

John (Britprius)

 

Yes I would agree that the parking brake works better in the forward direction than reverse.

John (Britprius)

 

Replace them.
I'll wager that the inboard surfaces are even worse.

 

Not a bad price at £23 delivered. Removing delivery cost around the same price as I paid nearly 18 months ago. The hole with the dark ring round it in the first picture is the parking brake adjuster hole.

Make sure when you fit the discs make sure you clean off all the anti rust coating particularly inside the drum and the inside flat face of the drum. If you do not do that area when the brake warms up the coating melts and runs onto the braking surface of the drum as it spins.

You may have to slacken the the brake shoe adjusters off to get the new drum/disc on. Inspecting the manual adjusters with the drum/discs off will allow you to see how they are adjusted and there relative positions.

John (Britprius)

 

I suggest you purchase some copper grease if you have not already. Put a thin smear of this on the back of the pads and on the edges where they move against the carrier, also on the anti rattle shims.

Can you tell us the supplier of the discs as this might help someone else in and around the UK.

Any advice required just ask.

John (Britprius)

 

Thanks and well done.

John (Britprius)

 

Still not too bad. I noticed this a lot on Ebay usually tucked away in some obscure place.

I should have informed you that the four stud version as fitted to the gen1 Prius are the same size and much cheaper, but then need to have four holes drilled to match the five stud version.

This is easyer to do than it sounds.

Bolting the old 5 stud disc to the new 4 stud disc through one wheel stud hole, making sure the drum center holes line up. Then with a hand held electric/battery drill, drill the other four holes. This drilling does not have to be supper accurate as the hole have lots of clearance on the wheel studs.

John (Britprius)

 

Those are the scariest instructions I've read in a long time

Regarding quantities, brake pads seem to always be one per axle while rotors are one per each.

 

You won't regret this.

Use a philosophy of "every 186,000 km whether it needs it or not"

 

Modding the discs is not as scary as it sounds. The wheel studs play no part in the positioning or the loading of the discs.

The centering is done by the large central hole the radial positioning is done by the small countersunk screw "often thrown away or missing", the discs mounting area is sandwiched between the wheel and the hub/wheel stud flange.

John (Britprius)