Rear brake caliper pistons. How hard is it to rewind back in?

[Grogey]

Hi,

How hard do you find it to wind in the rear caliper pistons? I have done mine twice now using a correct tool for this purpose . I have found it fairly hard. They go in all the way but they are quite stiff. I have watched youtube videos of this on the same T27 Avensis model and yes no one is spinning them in with one finger, but I have also watched videos of the same job on other vehicles where the pistons wind in with ease.

My vehicle has 170,000 miles on it and runs well. I am considering replacing or rebuilding the calipers as I think they might be on the way out due to this.

This is the link to the tool I use, but i bought mine for less at Eurocarparts.

https://www.halfords.com/tools/hand-tools/all-hand-tools/laser-brake-caliper-adjustable-rewind-tool--5751-113609.html

 

Cheers

[Infiniti]

1 hour ago, Grogey said:

Hi,

How hard do you find it to wind in the rear caliper pistons? I have done mine twice now using a correct tool for this purpose . I have found it fairly hard. They go in all the way but they are quite stiff. I have watched youtube videos of this on the same T27 Avensis model and yes no one is spinning them in with one finger, but I have also watched videos of the same job on other vehicles where the pistons wind in with ease.

My vehicle has 170,000 miles on it and runs well. I am considering replacing or rebuilding the calipers as I think they might be on the way out due to this.

This is the link to the tool I use, but i bought mine for less at Eurocarparts.

https://www.halfords.com/tools/hand-tools/all-hand-tools/laser-brake-caliper-adjustable-rewind-tool--5751-113609.html

 

Cheers

I did my Auris SR180 a few months back, and they were incredibly difficult to wind back in. However I put this down to probably needing a recondition/ replacement.

[flash22]

EPB ? if so you have to put it in service mode with a scan tool

[Grogey]

46 minutes ago, flash22 said:

EPB ? if so you have to put it in service mode with a scan tool

Hi flash22,

This model being 2010 doesn't or at least hasn't required any computer resets on previous brake pad changes. It's simply let off handbrake, rewind piston, replace pads. It has reset automatically after that.

As I understand it the piston is adjusted by the EPB by an internal screw thread. It is this thread that we have to wind back down. I understand that there will be friction between the piston and the screw, between the piston and it's cylinder walls, between the piston and the main seal and also between the piston and the outer expanding boot.

I'm not sure how service mode effects the mechanical resistance in this system?

If there is diagnostics that need to be completed when replacing rear breakpads on a 2010 Avensis can some one please confirm that?

 

Hi Infiniti

2 hours ago, Infiniti said:

I did my Auris SR180 a few months back, and they were incredibly difficult to wind back in. However I put this down to probably needing a recondition/ replacement.

I'm thinking similar too you. 

[Infiniti]

5 minutes ago, Grogey said:

Hi flash22,

This model being 2010 doesn't or at least hasn't required any computer resets on previous brake pad changes. It's simply let off handbrake, rewind piston, replace pads. It has reset automatically after that.

As I understand it the piston is adjusted by the EPB by an internal screw thread. It is this thread that we have to wind back down. I understand that there will be friction between the piston and the screw, between the piston and it's cylinder walls, between the piston and the main seal and also between the piston and the outer expanding boot.

I'm not sure how service mode effects the mechanical resistance in this system?

If there is diagnostics that need to be completed when replacing rear breakpads on a 2010 Avensis can some one please confirm that?

 

Hi Infiniti

I'm thinking similar too you. 

If it's any consolation, I'm still driving fine, did a brake bleed too and i'm braking very strong compared to before the pad change!

[JiiN]

15 minutes ago, Grogey said:

Hi flash22,

This model being 2010 doesn't or at least hasn't required any computer resets on previous brake pad changes. It's simply let off handbrake, rewind piston, replace pads. It has reset automatically after that.

As I understand it the piston is adjusted by the EPB by an internal screw thread. It is this thread that we have to wind back down. I understand that there will be friction between the piston and the screw, between the piston and it's cylinder walls, between the piston and the main seal and also between the piston and the outer expanding boot.

I'm not sure how service mode effects the mechanical resistance in this system?

If there is diagnostics that need to be completed when replacing rear breakpads on a 2010 Avensis can some one please confirm that?

 

Hi Infiniti

I'm thinking similar too you. 

I changed brake pads and discs while ago to my T27 and it didn't need any diagnostics. I checked with Techstream fault codes after brake replacement and there was no any fault codes and EPB works like a charm.

[flash22]

epb service mode releases the actuator(s) and allows free movement - its a service function not a diagnostics, on some cars the service tools can wind back the calipers for you

[Grogey]

1 hour ago, flash22 said:

epb service mode releases the actuator(s) and allows free movement - its a service function not a diagnostics, on some cars the service tools can wind back the calipers for you

Cheers for that. Anyone know if that can be done on a 2010 Avensis?

[JiiN]

2 hours ago, Grogey said:

Cheers for that. Anyone know if that can be done on a 2010 Avensis?

My 2010 Avensis didn't need anything to be done, than EPB normal button release, ignition off, gear to 1st and just manually rewind piston.

I used a tool similar than this: 

Left side anti-clockwise and right side clockwise.

And when rewinding pistons, You should also check the brake fluid at reservoir that the brake fluid level doesn't get too high.

[Grogey]

6 hours ago, JiiN said:

My 2010 Avensis didn't need anything to be done, than EPB normal button release, ignition off, gear to 1st and just manually rewind piston.

I used a tool similar than this: 

Left side anti-clockwise and right side clockwise.

And when rewinding pistons, You should also check the brake fluid at reservoir that the brake fluid level doesn't get too high.

Hi Jiin,

How easy did you find it? I'll go multiple choice to make it a bit easier to discuss what is a subjective experience. Feel free for anyone to answer by picking an option or somewhere between options. My car was a C. 

 

Options

A# It could be rewound easily without a special tool such as by using needle nose pliers or even just by bare hand.

B# It could be rewound easily using the tool without much force.

C# It could be rewound using the tool but needed full hand strength.

D# It could not be rewound using the tool without extending the tee handle for extra leverage.

 

Thanks for the interest. 

[JiiN]

7 minutes ago, Grogey said:

Hi Jiin,

How easy did you find it? I'll go multiple choice to make it a bit easier to discuss what is a subjective experience. Feel free for anyone to answer by picking an option or somewhere between options. My car was a C. 

 

Options

A# It could be rewound easily without a special tool such as by using needle nose pliers or even just by bare hand.

B# It could be rewound easily using the tool without much force.

C# It could be rewound using the tool but needed full hand strength.

D# It could not be rewound using the tool without extending the tee handle for extra leverage.

 

Thanks for the interest. 

I think it was somewhere between B and C. It took some force but not full hand strength. I opened brake fluid reservoir cap before piston rewind to release pressure (I'm not sure if it helps anything).

[Infiniti]

11 hours ago, JiiN said:

I think it was somewhere between B and C. It took some force but not full hand strength. I opened brake fluid reservoir cap before piston rewind to release pressure (I'm not sure if it helps anything).

I'd agree with you JiiN, same process too.

[Konrad C]

I have changed my rear brake pads, and when winding back the pistons (left and right handed as using the kit shown), makes sure the piston cut outs are horizontal to the caliper when you finish! This is important at it aids fitting the caliper over the new pads, which have a nipple on the back of the pads. If the caliper has to be forced on, then the piston or inner brake pad will be force to work at an angle, causing the pad to wear at a slant or the piston jam against the inside of caliper bore. The inner pad will wear faster than the outer pad, but because it is not as visible as the out brake pad, not easy to spot! 
Apart that, no diagnostic should be needed when replacing the rear brake pads. Not everyone has diagnostics anyway, plus using the wrong diagnostic tool can cripple the auto parking brake, as I learnt to my cost. Wrong diagnostics reset will delete the zero point setting of the g-force and clutch settings, giving warning/fault lights and message. The parking brake can only be operated manually, using the button. I fixed it myself using Techstream.