front drum brakes grabbing
#1
front drum brakes grabbing
my 62 Olds seems to have a problem with my front brakes grabbing hard almost throwing me into the dash , we have put new brakes on ,turned the drums down , I was told only way to stop it is to put disk brakes on the front , did anybody have same trouble with these older cars with drum brakes , any suggestion's on how to stop brakes from grabbing so hard , thanks Dennis
#2
Who told you this? Did you or he stop and think for a minute that hundreds of thousands of cars were built during this period as there were no disc brakes in 1962, and yet these cars did not have grabby brakes?
Have you you checked the service manual? There is a Diagnosis section in the Brakes section with possible reasons for grabby brakes. It's shown below. You say you "put new brakes on." That's not very informative. What parts, exactly, did you replace? Presumably your "new brakes" included new brake shoes, so we can rule out both B and C on the list as you say the drums have been turned. But there are other possibilities, some of which don't involve components at the wheel at all but rather involve the power brake unit.
Remember that it IS possible to make your brakes work correctly short of replacing them with discs. If it was your mechanic who told you that the only solution is discs, find another mechanic. If it was your brother-in-law, find another brother-in-law.
Have you you checked the service manual? There is a Diagnosis section in the Brakes section with possible reasons for grabby brakes. It's shown below. You say you "put new brakes on." That's not very informative. What parts, exactly, did you replace? Presumably your "new brakes" included new brake shoes, so we can rule out both B and C on the list as you say the drums have been turned. But there are other possibilities, some of which don't involve components at the wheel at all but rather involve the power brake unit.
Remember that it IS possible to make your brakes work correctly short of replacing them with discs. If it was your mechanic who told you that the only solution is discs, find another mechanic. If it was your brother-in-law, find another brother-in-law.
#4
As already stated, you should be able to remedy this issue without installing disc brakes up front.
#7
my 62 Olds seems to have a problem with my front brakes grabbing hard almost throwing me into the dash , we have put new brakes on ,turned the drums down , I was told only way to stop it is to put disk brakes on the front , did anybody have same trouble with these older cars with drum brakes , any suggestion's on how to stop brakes from grabbing so hard , thanks Dennis
Who ever told you disc brakes is the only fix I wouldn't listen to them anymore. Complete idiot.
#8
You know - there is a "leading" shoe, and a "trailing" shoe on each drum brake setup - double-check that you have your brake shoes oriented and assembled correctly. Getting these two shoes into the wrong position can lead to grabbiness. Take a look. You may find that you have two leading shoes on one side, and two trailing shoes on the other - instant recipe for less than stellar brake actions.
What others have suggested are also possibilities to check.
Also, is there ANY brake fluid leaking onto the brake shoe material, or contaminated brake linings? THEY can ALSO become grabby - only solution is to stop the source of brake fluid/wheel grease, Brakleen inside the drums, and replace the affected brake shoes,
Finally, you mentioned that the drums were turned - is the entire brake shoe area of the drum SMOOTH - NO lips or grooves? Is the drum diameter within the accepted factory spec, or, are they too oversized/large, thereby out of spec and unable to provide the correct sized stopping surface for the shoes to ride against?
While discs are desireable in this day and age, the old drum brakes can perform well enough when set-up correctly - especially if you are fortunate to have aluminum finned drums, which dissipate the heat quite well during fast stops - have BIG factory finned aluminum drums on a 1970 Buick Riv, my 1963 go-fast stick Pontiac Catalina (factory 8-lug wheels with aluminum finned drums). Don't count on the drum brakes being able to stop you from triple-digit speeds - stab them hard at a buck-10, and they will get you down to about 40, before the drum brakes begin fading away. Ask me how I know . . .
Good luck.
Table-Top Flat
What others have suggested are also possibilities to check.
Also, is there ANY brake fluid leaking onto the brake shoe material, or contaminated brake linings? THEY can ALSO become grabby - only solution is to stop the source of brake fluid/wheel grease, Brakleen inside the drums, and replace the affected brake shoes,
Finally, you mentioned that the drums were turned - is the entire brake shoe area of the drum SMOOTH - NO lips or grooves? Is the drum diameter within the accepted factory spec, or, are they too oversized/large, thereby out of spec and unable to provide the correct sized stopping surface for the shoes to ride against?
While discs are desireable in this day and age, the old drum brakes can perform well enough when set-up correctly - especially if you are fortunate to have aluminum finned drums, which dissipate the heat quite well during fast stops - have BIG factory finned aluminum drums on a 1970 Buick Riv, my 1963 go-fast stick Pontiac Catalina (factory 8-lug wheels with aluminum finned drums). Don't count on the drum brakes being able to stop you from triple-digit speeds - stab them hard at a buck-10, and they will get you down to about 40, before the drum brakes begin fading away. Ask me how I know . . .
Good luck.
Table-Top Flat
Last edited by Torque Monster; May 23rd, 2019 at 07:11 PM.
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