Drum brakes - leading and lagging edge

[AliK]

I’ve read about leading and lagging edge of brake shoes on drum brakes especially as mine were installed incorrectly by the PO as advised by a mechanic.

I think I have this the right way around - would someone kindly confirm for me or tell me otherwise?

 

[Farmer42]

Looks right to me Ali. That is also how the diagram looks in the Haynes manuals although someone will now probably tell me that the manual is wrong.

 

[AliK]

Thanks Mr Farmer! The trouble with the Haynes manual was that I couldn’t tell which side it was.

As I understand it, the bit with the least brake pad material should have the drum spin into it (if that makes sense).

 

[toopy]

Thanks Mr Farmer! The trouble with the Haynes manual was that I couldn’t tell which side it was.

As I understand it, the bit with the least brake pad material should have the drum spin into it (if that makes sense).

That is my understanding also, something to do with the way the spinning drum grabs the front of the shoe forcing it downwards putting more pressure on the trailing edge of the shoe and so increasing the braking effect.

 

[Bazzateer]

Ali,
It's worth 5 mins with a file to chamfer the leading edges as well.

 

[AliK]

Ali,
It's worth 5 mins with a file to chamfer the leading edges as well.

Good advice sir!!! I saw that on the set I took off and wondered how it could possibly have worn that way! [emoji106]

That is my understanding also, something to do with the way the spinning drum grabs the front of the shoe forcing it downwards putting more pressure on the trailing edge of the shoe and so increasing the braking effect.

Yes that’s what I read too - trying to visualise it though is a little harder

 

[moggy240]

From the nissan manual. Looks like you have it correct. I think I might need to check mine now.

 

[AliK]

Thanks Moggy! The first diagram was the one I was looking at in Haynes but I couldn’t figure out which side it was

Looking at it again I can see with the position of the handbrake mechanism that it is the same side that I was doing.

 

[jonbills]

Are you sure you could even put them on the wrong way Ali? I think the location of the hole for the handbrake lever makes it pretty hard to put them on wrong.

 

[AliK]

Are you sure you could even put them on the wrong way Ali? I think the location of the hole for the handbrake lever makes it pretty hard to put them on wrong.

Yes sir, Put a line vertically in the middle and flip the image 180 and you’re there - quite easy to do.

There are two variations on the brake shoes. The ones that fit mine are uni-sex so to speak so you can fit them on either side.

 

[Rob Gaskin]

... The ones that fit mine are uni-sex so to speak so you can fit them on either side.

Can't you spell ambidextrous?

 

[jonbills]

Yes sir, Put a line vertically in the middle and flip the image 180 and you’re there - quite easy to do.

There are two variations on the brake shoes. The ones that fit mine are uni-sex so to speak so you can fit them on either side.

so you could put the one not attached to the handbrake lever in either way up?
hmm, I might have to look as well. [emoji4]

 

[AliK]

so you could put the one not attached to the handbrake lever in either way up?
hmm, I might have to look as well. [emoji4]

I think yours being an early 260 may have the other shoes that may not be uni-sex. Would be interesting to see - take a photo and show us yours!

I think they look like this ...

 

[AliK]

Can't you spell ambidextrous?

On that note why does dyslexic have to be so complex for dyslexics to have to describe themselves!?

 

[moggy240]

I had to adjust my rear cylinders and I did enlarged the adjusting hole as I had it before where you just can't see anything of the adjuster and it's a nightmare to slacken the shoes off to remove the drums. Just used a step drill from the back of the drum to open it up to 14mm with a 16mm step so I could fit a rubber grommet.

 

[Paul_S]

I had to adjust my rear cylinders and I did enlarged the adjusting hole as I had it before where you just can't see anything of the adjuster and it's a nightmare to slacken the shoes off to remove the drums. Just used a step drill from the back of the drum to open it up to 14mm with a 16mm step so I could fit a rubber grommet.

I like that mod! I think I might copy that the next time I have the rear jacked up

 

[Rob Gaskin]

I had to adjust my rear cylinders and I did enlarged the adjusting hole as I had it before where you just can't see anything of the adjuster and it's a nightmare to slacken the shoes off to remove the drums. Just used a step drill from the back of the drum to open it up to 14mm with a 16mm step so I could fit a rubber grommet.

I hope your re-balanced it.