2.75 vs 3 inch front brake shoe conversion - same spindle?

MoPar~Man

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Was the 2.75" front shoe the standard size for all non-wagon, non-440 C-bodies from '65 right up to when disk brakes became standard?

I imagine that police or taxi or otherwise a "heavy duty" brake option would have given you the 3" drums?

I see some 3" drums on rockauto that are indicated as being for wagons? Thing is, I don't think I'm seeing any 3" shoes being listed.

If you wanted to beef up the front brakes a little, is it just a matter of throwing on the wider "wagon" drum, and finding the 3" shoes?
 
Nope, not that easy.
To upgrade from the 2.75 to 3 inch drums you need the backing plates, wheel cylinders and all related hold down kit.
Which means separating the knuckle ftom the suspension.
 
In all of the various brake widths, the centerline of the brake shoes should be in the same place, related to the spindle the backing plates mount to. Wider shoes mean more offset inward for the backing plates and similar offsets to the outside for the drums. With the mounting surface for the wheels in the same place. Wheel cyl placements would not be affected by the inward offsets, I suspect, so same cyls used. Attaching hardware would be width-specific, but the adjusting mechanism should be common.

The availability of quality brake drums in the correct widths might lead to more disc brake conversions, I suspect.

You CAN get your linings upgraded to something more-metallic, for a cost. Seems like the Muscle Car Brakes linings are over $400.00 frt/rr for 11x3 and 11x2.5 sizings?

CBODY67
 
Here's an old thread:


@69furyIII hasn't been around since last November so can't ask him how this worked out.

Another thread:


I note this: "He is correct that you cannot change the shoe width. The top pin on the backing plates is set for the width."

Yes, that pivot pin would have to dimensionally match the shoe, but is that the only difference between backing plates - that they're the same plate with different pins?

A slight diversion -> I wonder if asbestos linings of years ago made drum brakes more effective in the past than they are today...

But the pin can be made to take a lot of different shoe widths so I'm not exactly getting that part.

@ascari hasn't been around here for a few months, it would be good to get an update from him.

@mobileparts do you still have NOS 2.75 or 3 inch asbestos shoes? I have to wonder what age does to these linings and bonding glues.

----------------

"I had a 68 Chrysler New Yorker as my first car. It had 11 X 3 drums on all four wheels. Later I had a few 68 Newport's as well but they had the smaller 2.75 inch wide shoes on the rear."

I could use a reality-check on that.
----------------
 
In all of the various brake widths, the centerline of the brake shoes should be in the same place, related to the spindle the backing plates mount to. Wider shoes mean more offset inward for the backing plates and similar offsets to the outside for the drums. With the mounting surface for the wheels in the same place. Wheel cyl placements would not be affected by the inward offsets, I suspect, so same cyls used. Attaching hardware would be width-specific, but the adjusting mechanism should be common.

The availability of quality brake drums in the correct widths might lead to more disc brake conversions, I suspect.

You CAN get your linings upgraded to something more-metallic, for a cost. Seems like the Muscle Car Brakes linings are over $400.00 frt/rr for 11x3 and 11x2.5 sizings?

CBODY67
Checked my parts bok.
Yup. Wheel cylinder same for wider drums. Just left and right are different.
Here's an old thread:

[/URL]

@69furyIII hasn't been around since last November so can't ask him how this worked out.

Another thread:

[/URL]

I note this: "He is correct that you cannot change the shoe width. The top pin on the backing plates is set for the width."

Yes, that pivot pin would have to dimensionally match the shoe, but is that the only difference between backing plates - that they're the same plate with different pins?

A slight diversion -> I wonder if asbestos linings of years ago made drum brakes more effective in the past than they are today...

But the pin can be made to take a lot of different shoe widths so I'm not exactly getting that part.

@ascari hasn't been around here for a few months, it would be good to get an update from him.

@mobileparts do you still have NOS 2.75 or 3 inch asbestos shoes? I have to wonder what age does to these linings and bonding glues.

----------------
[/URL]

"I had a 68 Chrysler New Yorker as my first car. It had 11 X 3 drums on all four wheels. Later I had a few 68 Newport's as well but they had the smaller 2.75 inch wide shoes on the rear."

I could use a reality-check on that.
----------------
Basically, 440 powered C bodies got front 11x3 drums.
All others were 11x2.75
Except tow package had 11x3 on all 4 corners and were manually adjusted ( no automatic adjusters)
 
I have *** N.O.S. *** U.S.A. made *** 11 " x 3 " Front Brake Drums......
I have *** N.O.S. *** U.S.A. made *** 11 " x 2 1 / 2 " Rear Brake Drums.......

I have *** N.O.S. *** U.S.A. made *** 11 " x 2 3 / 4 " Front Brake Drums......
I have *** N.O.S. *** U.S.A. made *** 11 " x 2 " Rear Brake Drums......

I have *** N.O.S. *** Asbestos *** 11 " x 3 " *** Front Brake Shoes...... ( not many remaining )
I have *** N.O.S. *** Asbestos *** 11 " x 2 1 / 2 " *** Rear Brake Shoes...... ( not many remaining )

I have *** N.O.S. *** Asbestos *** 11 " x 2 3 / 4 " *** Front Brake Shoes..... ( not many remaining )
I have *** N.O.S. *** Asbestos *** 11 " x 2 " *** Rear Brake Shoes....... ( not many remaining )

If I sell as many *** N.O.S. *** Asbestos *** Brake Pads & Brake Shoes this year @ Chryslers @ Carlisle as I did last year --- there are some numbers
that I will indeed be out of ---- and the MAJOR question is, " Will I ( ever ) find more ??? " Remember, Asbestos Laws have made the Manufacture of Asbestos Brake Pads and Shoes Illegal for 31 years in the U.S.A. and 23 years in Canada now.....

It is NOT illegal to transact on *** N.O.S. *** Asbestos *** Brake Products --- they are " grandfathered in " .....

*** N.O.S. *** ASBESTOS *** can NOT be duplicated.... Manufacturers spent a lot of money on R & D ( research and development ) to attempt to duplicate the braking capabilities of *** Asbestos *** --- and finally, just gave up 15 years ago.....

Asbestos is the softest , smooooooothest braking system known to mankind, and does not rip up Brake Drums to smithereens.... It is far and away the best
Product anybody can utilize to successfully STOP a real vehicle....

As someone mentioned ^^^ above ^^^ some new-fangled company is selling some highly metallic Brake Shoes at over $ 200 / set ( Holy Schniekies !!! )
and they ( MAY ) stop a vehicle --- but they WILL rip up Brake Drums to smithereens in no time.....

And, lastly, I don't do USED --- so N O Spindles and N O Backing Plates......

Craig.....
 
I have *** N.O.S. *** U.S.A. made *** 11 " x 3 " Front Brake Drums......
I have *** N.O.S. *** U.S.A. made *** 11 " x 2 1 / 2 " Rear Brake Drums.......

I have *** N.O.S. *** U.S.A. made *** 11 " x 2 3 / 4 " Front Brake Drums......
I have *** N.O.S. *** U.S.A. made *** 11 " x 2 " Rear Brake Drums......

I have *** N.O.S. *** Asbestos *** 11 " x 3 " *** Front Brake Shoes...... ( not many remaining )
I have *** N.O.S. *** Asbestos *** 11 " x 2 1 / 2 " *** Rear Brake Shoes...... ( not many remaining )

I have *** N.O.S. *** Asbestos *** 11 " x 2 3 / 4 " *** Front Brake Shoes..... ( not many remaining )
I have *** N.O.S. *** Asbestos *** 11 " x 2 " *** Rear Brake Shoes....... ( not many remaining )

If I sell as many *** N.O.S. *** Asbestos *** Brake Pads & Brake Shoes this year @ Chryslers @ Carlisle as I did last year --- there are some numbers
that I will indeed be out of ---- and the MAJOR question is, " Will I ( ever ) find more ??? " Remember, Asbestos Laws have made the Manufacture of Asbestos Brake Pads and Shoes Illegal for 31 years in the U.S.A. and 23 years in Canada now.....

It is NOT illegal to transact on *** N.O.S. *** Asbestos *** Brake Products --- they are " grandfathered in " .....

*** N.O.S. *** ASBESTOS *** can NOT be duplicated.... Manufacturers spent a lot of money on R & D ( research and development ) to attempt to duplicate the braking capabilities of *** Asbestos *** --- and finally, just gave up 15 years ago.....

Asbestos is the softest , smooooooothest braking system known to mankind, and does not rip up Brake Drums to smithereens.... It is far and away the best
Product anybody can utilize to successfully STOP a real vehicle....

As someone mentioned ^^^ above ^^^ some new-fangled company is selling some highly metallic Brake Shoes at over $ 200 / set ( Holy Schniekies !!! )
and they ( MAY ) stop a vehicle --- but they WILL rip up Brake Drums to smithereens in no time.....

And, lastly, I don't do USED --- so N O Spindles and N O Backing Plates......

Craig.....
 
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