my wagner master brake catalog only lists 11x2 1/2" rear drums as available on the charger. the only listing i could find for 11x3" rear drums were for chrysler new yorkers, newports, and imperials. this goes from 1963-1976. if there is indeed 11x3" brakes on your charger, i will have to say they were swapped on from a new yorker or a newport, as the imperial had a 5" bolt pattern. also, my 69 FSM only lists 11x2 1/2" rear drums even on police and heavy[taxi] duty brakes.

Thanks for all your time. But there is still the main question I have that is being lost because of the 'what is factory correct' discussion.

Let me rephrase: I need to order rear brake shoes for the drums on my Charger based on what is on there 'now'. The car is in storage so I must blindly order the shoes etc based on the picture I provided. Are the rear brake drums in my picture with number 36418 11x3 or 11x2.5? Thanks.

i think the number you have on your drum may be a casting # instead of a part #. all the info i have on interchange numbers indicate the 69 charger R/T, coronet R/T, super bee, road runner[with drums], or belvedere, charger and coronet with heavy duty brakes or with trailer towing package had only 11x2 1/2 rear drums. that factory part # is : 2405789.[7 digits] if it indeed has 11x3 drums, it more and more leads me to believe they were swapped. the only way i believe possible to be sure is take the drum off and measure. i know that is not what you want to here, but before you spend the money i believe it's now the only way to be 100% positive. 11x2 1/2" stuff is pretty common [unless you want absolutely NOS parts] as it was used in trucks and vans for many years after the muscle stuff was gone, and is interchangeable. i have done it countless times. i can't say how many vendors chrysler used for their drums, so someone other than me will have to chime in for this info. let us know what you find out.

the alternate part # is 3004933. this is also an 11x2 1/2" drum. this is the drum with cooling fins used in 69-70 on all mentioned above plus fury, GTX, monaco, newport, new yorker, chrysler 300, polara, 70 barracuda, 70 challenger with heavy duty or trailer towing option, 70 cuda, and 70 challenger RT with drum brakes.

OK thanks for your help. I understand you can only give me the info you have and been very nice to provide it. The reason I was hoping to get an answer by using the 36418 casting number was the post below I found on this thread:

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Post:
"So shoes are 2 7/8 wide
drums have a part number 36418 also mwyb5 c21.
Found out they are 11x3 from factory on rear. "

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I was hoping for confirmation being that he has the same casting number as me and he is sure his are 11x3, that would mean mine are that size too. (again remember this is not about if its factory correct or not but instead just what is on my car which I can't access due to it being in storage and need to order brake shoes etc for).

In your opinion, being mine is the same casting number would it likely have to also be the same 11x3 size? (I would assume you can't have the same casting number on 11x3 and 11x2.5 parts, no?) I promise this to be the last question regarding this. Thanks.

don't be afraid of asking questions ! the only "dumb" question is the one not asked ! the 2 7/8" wide dimension gives me reason to wonder because in measuring mopar brake shoe lining for 50+ years, they have all been 2 1/2" or 3" wide. so at 2 7/8", man i don't know. and part numbers are not casting numbers. as to what someone else has on their car, anything is possible. i owned a junk yard from 1970 to 1985, and the ONLY 3" wide drums i came across was on imperials, newports [very rare] wagons with the tow package, and newyorkers. to have you order 3" replacement parts because someone claimed they were factory, i would, in all sincerity, have to have more than one person confirm those were indeed factory installed. if you could round up the necessary parts and find out the drums were 2 1/2" on your car, the backing plates, in my opinion, would really tough to come up with to complete the swap. please keep us updated on this topic. we can all learn from each other. one infamous quote is : "never say never with mopar"....

If I can piggy back on this thread, I'd like to ask another related question. It's actually to do with the 4-wheel HD drums on my '70 Challenger, but I suspect the answer will be the same. Each of my drums have two ports in the back for adjustments. The dust covers were missing on all 4 corners. Has anyone got a pic of what the correct rubber plugs look like?

Like these:

http://www.ebay.com/itm/BRAKE-DRUM-ADJUSTING-HOLE-DUST-COVER-PLUG-RUBBER-/122000811017?hash=item1c67d0a409:g:NKwAAOSwstxVd3E6&vxp=mtr

The picture posted earlier in this thread looks like a standard 11 x 2 1/2" drum.

Thanks, Tman.

CENTRIC 12363016 part is 11" rear drum and friction surface is 2.93 inches wide. Found this part# at Rockauto under 69 Coronet with 440 motor. It is very close to 3 inch wide.

CENTRIC 11103360 brake shoe for 3 inch wide 11" drum. for both front and rear. Found this application under 69 GTX.

There are much more part #s for 11X2.5 drum and shoes though.

So if you definitely need 3" wide drum and shoes, it is available.

Centric # 123.63016 is a 11 x 2 1/2" rear drum.

Centric # 111.03360 is a set of 11 x 3" C/B body front brake shoes and 11 x 3" C body rear brake shoes.

the friction surface of all drums will be wider than the shoe width. note the large rust ridge present when you take drum off to replace parts ? when drums are turned, that ridge becomes part of the "friction surface". a 2.93 friction surface is for 2 1/2" wide brake shoes. 3" wide shoes would lock that drum up solid when the wheel was bolted on no matter how the shoes were adjusted.

edit : brake shoes, as a rule, use the same shoe core for both front and rear applications. that is why there are unused holes and shapes present. "most" shoe material is also the same [unless you are talking a performance shoe from a company that deals with specialty lining], and both sets have a primary[short] and secondary[long] lining, where the primary goes to the front, and the secondary goes to the rear.

I thought some might find this interesting regarding Classic Industries listing some 11x3 rear brake parts for late 60s B-bodies. I just came across this an hour ago.




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