Front Drum Brake liner

[OldGerman]

I'm in process to rework my brakes, because one rear wheel cylinder was leaking and I had poor front brake stopping performance in the past years now. I have a redone original brake booster and a new dual master brake cylinder.

While the car is on hoist, I'm checking the front brakes for wear and for any brake fluid leak contamination.

Both front drums are clean, no leak found.

 

I  have a set of new heavy duty (what ever that means) riveted Dorman Brake liners (black color) and a set of Centric liners (gold color). I noticed a difference in the position of the shorter primary liners between both sets, but the liners have similar total length.

 

Question: does this even matter and if yes, what is wrong or right ?

I would think the black Dorman brake shoe would be more "agressive" because of the liner is closer to the upper pivot point.

 

Thank you for sharing your thoughts.

 

Picture below shows the primary brake shoes from Centric (left/gold color) and Dorman (right/black Color). Please see the difference in liner offset.

Edited June 21 by OldGerman
Correction (see edit history)

[JFranklin]

Flip a coin, heads the dark ones, tails the other.

[mobileparts]

Sadly, they are both Chineseum garbage , that will rip up very expensive Brake Drums 

to smithereens….

 

 

[JFranklin]

52 minutes ago, mobileparts said:

..., that will rip up very expensive Brake Drums 

to smithereens….

 

 

Sounds a bit extreme to me. Any lining is softer than cast iron or steel.

[NTX5467]

It is common for brake linings on one wheel to have different lengths of linings.  One is termed "primary" and the other one is "secondary".  Check the factory service manual to see which one goes toward the front end of the car and which one goes toward the rear of the car.

 

One set if bonded and the other one is riveted.  No performance differences, just that the bonded lining can be run until there is no more as there will be lining left when the rivets hit the brake drum.

 

NTX5467

[OldGerman]

3 hours ago, NTX5467 said:

It is common for brake linings on one wheel to have different lengths of linings.  One is termed "primary" and the other one is "secondary".  Check the factory service manual to see which one goes toward the front end of the car and which one goes toward the rear of the car.

 

One set if bonded and the other one is riveted.  No performance differences, just that the bonded lining can be run until there is no more as there will be lining left when the rivets hit the brake drum.

 

NTX5467

The picture shows two primary brake shoes from different Brands (Dorman and Centric) with different offset of the liner.  

I have a service manual but it does not deal with such quality differences in service parts. 

[EmTee]

The placement on riveted shoe looks like what I am accustomed to seeing.  I think that one will likely perform a bit better, as usually most of the wear occurs near the middle of the shoe.  Worn shoes will generally have thicker material left at the adjuster end.  Will you be able to notice a performance difference?  Maybe, but I expect the friction material will have a bigger impact on how the brakes perform.  To me, the riveted shoe looks like better quality.

[OldGerman]

8 hours ago, mobileparts said:

Sadly, they are both Chineseum garbage , that will rip up very expensive Brake Drums 

to smithereens….

 

 

Do you know any certified source not suppling Chineseum made stuff ?   I think no one manufactures 50+ year old service parts in USA and EU anymore. Our wages are to high.

[EmTee]

7 minutes ago, OldGerman said:

Do you know any certified source not suppling Chineseum made stuff ?

I think he 'knows somebody'... 

[NTX5467]

PM sent.  

 

There are "industry specs" determined by the car manufacturers for brake lining lengths.  NO difference between brands in that respect, or at least as much as indicated.  Which tends to make me suspect one of them is not for your vehicle.

 

Just some thoughts,

NTX5467

[RivNut]

Turn your drums ( they can be turned with the hub in place ) Then have them measured. The factory specs state that anything over 12.080” is too far out and not safe. 

[Frank DuVal]

On 6/20/2024 at 11:37 PM, NTX5467 said:

Check the factory service manual to see which one goes toward the front end of the car and which one goes toward the rear of the car.

On a Duo-Servo, which is why there is different length primary and secondary shoes, I have only seen the shorter lining towards the front of the car and the longer lining toward the rear of the car. Have you seen it the other way around correctly installed? Yes, I have seen them the wrong way, but it was incorrectly installed.

 

 

 

If the drums look good DO NOT TURN THEM!!!!!!!!!! Metal scraped off is metal gone for good. I'm sure brake drums are not readily available in Germany, nor America, for this car.

 

 

 

 

On 6/21/2024 at 10:13 AM, NTX5467 said:

NO difference between brands in that respect, or at least as much as indicated. 

I see you have not bought brake shoes in a while, at least the new made brake shoes.... Ha!  Heck, on #189 shoes we are now cutting one shoe lining shorter to make a primary shoe since they come as a set of four equal length linings on many makes. 😮  Wasn't that movie line "specs? We don't need no stinkin' specs!"🤣

Edited June 23 by Frank DuVal (see edit history)

[NTX5467]

Past the original A.M.A. Specs the OEMs did, I suspect that an OEM would not alter them past the then-current year model products.  Which could well mean that the aftermarket seller "changed the specs" to something more-near something they already sold.  As in "inventory consolidation".  That could explain the differences mentioned.

 

The A.M.A. Specs only mentioned sizes of the brake frictions.  "D52" is a common 1970s-era GM front disc brake pad size spec.  Fits a huge number of vehicles from cars to C30 trucks, BUT the differences come in the friction material applied to that basic pad.  In GM, that generated a lot of different OEM part numbers.  In the aftermarket, it generates lots of prefixes and suffixes surrounding the common "D52" part of the aftermarket part number, within a particular brand.

 

The A.M.A. Specs had to be finalized prior to the start of vehicle production, which means they were finalized, probably, in the June prior to the August/September start of that model year production.  Revisions might be made during that particular production year, but not during the later model year.  

 

NTX5467

[gungeey]

On 6/20/2024 at 3:20 PM, OldGerman said:

I'm in process to rework my brakes, because one rear wheel cylinder was leaking and I had poor front brake stopping performance in the past years now. I have a redone original brake booster and a new dual master brake cylinder.

While the car is on hoist, I'm checking the front brakes for wear and for any brake fluid leak contamination.

Both front drums are clean, no leak found.

 

I  have a set of new heavy duty (what ever that means) riveted Dorman Brake liners (black color) and a set of Centric liners (gold color). I noticed a difference in the position of the shorter primary liners between both sets, but the liners have similar total length.

 

Question: does this even matter and if yes, what is wrong or right ?

I would think the black Dorman brake shoe would be more "agressive" because of the liner is closer to the upper pivot point.

 

Thank you for sharing your thoughts.

 

Picture below shows the primary brake shoes from Centric (left/gold color) and Dorman (right/black Color). Please see the difference in liner offset.

Frank, Below are factory shoes F&R. Notice the hand ground taper on both ends of all shoes. It's a nominal 3/4".

Front shoes 2 1/4" wide

Rear.              2"

 

Front length:  Pri 10 3/4" Sec 13 1/2"

Rear.               Pri 10"        Sec 13 1/4"

 

Of course you are dictated by what you have available.

My own opinion is avoid bonded shoes from China

Hope that's of use to you.

 

[Frank DuVal]

I know what they should look like. As I said, I cut #189 shoes (not a Buick part that I know of) to be like factory length linings.

 

Our friend in Germany needs to know what to do. He has two sets of shoes and they do not match. Your pictures may help him decide.  👍  I too would go with the riveted linings. Also on new shoes holes may need to be enlarged to fit e-brake pins, etc.

[gungeey]

6 hours ago, Frank DuVal said:

I know what they should look like. As I said, I cut #189 shoes (not a Buick part that I know of) to be like factory length linings.

 

Our friend in Germany needs to know what to do. He has two sets of shoes and they do not match. Your pictures may help him decide.  👍  I too would go with the riveted linings. Also on new shoes holes may need to be enlarged to fit e-brake pins, etc.

Old German is named Frank also 👍 

[60FlatTop]

Since 1993 I have had all my drum brake shoe jobs relined by a local company, Rochester Clutch and Brake. I was introduced to their brake service by a friend who specialized in making RR Sliver Clouds stop. I drop off my drums and old shoes. Phil, the current generation owner arcs, grinds and fits each shoe with fresh non-asbestos lining. They have three grades of stopping power. I pick the middle and have always been happy with the results.

 

I have never had them do disc brake pads for me but I may try them on my '05 Cadillac when it comes due.

 

My experience with aged brake linings appears to show a loss of stopping power over time. Cars with old but not worn linings have had stopping problems cured by replacing the shoes. I have never seen durometer tests comparing old to new but I think some outgasing  of the volatiles may reduce flexibility over time. I replaced my oldest set about 5 years old, at 20 years, for that reason just as a precaution.

[OldGerman]

I'm also tending towards the riveted Dorman shoes.  Thank you for your thoughts !

No one sells just the liners with a set of rivets for do it yourself ?

That is what I always did 30years ago on my old Opels

 

[RivNut]

My dad who was a professional Buick mechanic for years liked riveted shoes. He said the holes for the rivets gave the dust a place to accumulate.  

[60FlatTop]

Technology changes. When I took my shoes in to be relined in 2020 Phil looked at the riveted lining and said "We didn't do these. We only bond them". I said "Your uncle did them in 1993." My new ones are bonded. Just like the heat shields on spacecraft that withstands 5,000 degrees F. on reentry. Good enough for me.

 

[OldGerman]

12 hours ago, 60FlatTop said:

Technology changes. When I took my shoes in to be relined in 2020 Phil looked at the riveted lining and said "We didn't do these. We only bond them". I said "Your uncle did them in 1993." My new ones are bonded. Just like the heat shields on spacecraft that withstands 5,000 degrees F. on reentry. Good enough for me.

 

I need such a solid wheel chair for my garage. Looks to be very robust. Nowadays you only get plastic garbage.  

[60FlatTop]

4 hours ago, OldGerman said:

need such a solid wheel chair for my garage. Looks to be very robust. Nowadays you only get plastic garbage.  

That rolling seat has been with me so long I forgot where it came from. If I needed a replacement Williams Tools makes a good one for about $70. They make tools for Snap On. A couple years ago I bought a Williams creeper for $120 that was a dead ringer for the $325 S-O.