['ol Pinion head]

Hello,
Need the spec for when an 8 lug drum is too far gone & should be relined or go to oversized shoes. Do not have any pre '69 service manual's. ThanKs!!!

['ol Pinion head]

Hello,
Need the spec for when an 8 lug drum is too far gone & should be relined or go to oversized shoes. Do not have any pre '69 service manual's. ThanKs!!!

[Zimtok]

My 1965 Chasiss manual states that the 11" drums,,,,

"cannot be out of round, including taper for width, max .005 front and .006 rear."

"indicator shall not change more than .0005" in any inch of circumference"

Nothing is said about the min thickness of the steel drum inserts on the aluminum drums.

I would think that because the internal parts of the brakes are the same for the standard drums and the heavy duty (aluminum) drums, that the internal diameter specs would be the same for both.

The manual does not give the min/max specs for resurfacing the drums.

['ol Pinion head]

Zimtok,
Thanks for your response. I'm having a real hard time, even finding minimum spec's for non 8 lug big Pontiac's in this year range. I use O'Reilly's here in town, to turn my drums & their spec's only go back to '70. I would think a '70 big Pontiac steel drum would be same diameter inside as '65 drum. Better ck my parts books just to be sure

[Heybuck]

Page 5-7 of the 1965 Chassis Manual

"Inspection and Cleaning"

.......... CAUTION: Removing material from brake drum reduces the strength of the drum and also its ability to transfer heat. Never remove more than is absolutely nesessary AND IN NO CASE remove more than 0.030" (increasing diameter by 0.060") After a drum is turned down, be sure the drum is free of all metal particles. Whenever a drum is turned down, the drum on the opposite side should also be turned. If the drum diameter is less than 0.030" oversize(11.030") after refinishing, standard linings may be installed. If drum diameter is 11.030" - 11.060", then oversize linings must be installed.

*********************************************

ALL brake assemblies use the same (inside diameter) 11" drum but there are TWO types of heavy duty brakes.

Standard 8 Lugs and Heavy duty Alloy drums which require a 15" wheel. These heavy duty alloy drums have a standard 5 bolt pattern. When the 15" type drums are used, a metal impregnated lining was originally used. Ambulance and Police cars had these heavy duty drums and 15" wheels.

You can bolt a 15" wheel onto a standard iron drum but you can't bolt a 14" wheel onto the heavy duty alloy drums.

[ May 02, 2002, 07:09 PM: Message edited by: Heybuck ]