Drums from a 7" 1/4 fit on 8" 1/4?
- Thread starter pylle66
- Start date
-
whitepunkonnitro
Well-Known Member
What size rear brakes? What size bolt pattern?
Alaskan_TA
Well-Known Member
Backing plates interchange, they will fit the 8 3/4 also.
But you may need LBP drums.
But you may need LBP drums.
I love all the backing plate myths! I agree they all fit.
whitepunkonnitro
Well-Known Member
Wrong. Backing plates only interchange from 74-up BBP 7.25s. All of the earlier ones are 4 bolt.
8.75, 8.25 and BBP 7.25 all interchange.
Awesome! And where would you find these drums, if i wanted them in the future? If you can provide a link. Thanks!
I have drilled the fifth whole out the offsets are the same at least in my experience.
Check rock auto to start, there is a discount in the discount link also.
Standard rear brakes, so i guess 10" (?). Large bolt pattern, 4.5 x 5
You need the width also. That depends on the offset of the backing plates. They interchange by fit on the axel tube but have different offsets for the shoe width.
Ok whats the application (car) and what rear is it. And what do you currently have in parts?
Oh just noticed where you are, Shipping is a killer to there. Just helped out Anders and it was crazy on the shipping.
Yeah, but I'm only doing groundwork. My axle is from a F-body and i only have the housing. Just wanted to find out if brakes were something i had to look at too, or if I could be off using the old ones.
Tony @whitepunkonnitro your more versed on these there are 1 34 and 2.5 for ten in brakes? And the 2.5 backing plates are more offset in if I remember?
whitepunkonnitro
Well-Known Member
Yes, the offset is way different
whitepunkonnitro
Well-Known Member
You can't, the size of the whole pocket is different.
Sedanman
67-9 Valiant specialist
IF that F body 8 1/4 has 10" brakes order drums for a Diplomat. They are also 10x2.5
leblanc
member 2883
Can't you get drums from ''Summit'' and others? Just google mopar 8 1/4'' brake drums and pick your best option.
Sure I can, I just wanted to know if I absolutely had to.
Alaskan_TA
Well-Known Member
If you have them what type of rear is it 7 1/4, 8 1/4
I have to look could have sworn I did that once. I should have a couple of pairs left have to look again. Thanks.
Ok so you have a bare housing that is a 7 1/4 from a f body and no internals? so we are all on the same page.
Agreed, this has turned a bit confusing. My impression is the OP has an early A w/a 7 1/4 rear, and is planning to put an F body 8 1/4 in it. If so the OP has a lot more to
worry about than drums! The obvious answer is no, the drums don't work from any 4" bolt pattern axle, 9 or 10". The F body could've come with 10 or 11 X 2.5", and as
Tony stated, the only 7 1/4 compatible brakes are the '73& up 4.5" bolt pattern, which were 10 X 2.5". The 10 X 2.5" drum is as common as dirt as these get, You should not
have trouble finding them, just deciding where you want to purchase. If the 8 1/4 has the 11" brakes, they are also still available as well, but the OP stated std..................
worry about than drums! The obvious answer is no, the drums don't work from any 4" bolt pattern axle, 9 or 10". The F body could've come with 10 or 11 X 2.5", and as
Tony stated, the only 7 1/4 compatible brakes are the '73& up 4.5" bolt pattern, which were 10 X 2.5". The 10 X 2.5" drum is as common as dirt as these get, You should not
have trouble finding them, just deciding where you want to purchase. If the 8 1/4 has the 11" brakes, they are also still available as well, but the OP stated std..................
Trevor B
Well-Known Member
So... to be clear: the complete drum brake package (from backing plates outward) from any 1973 and later 7.25, 8.25, or 8.75 can be transferred to another 1973 and later rear end?
If the 7.25 is the large bolt pattern, yes. In A bodies, they produced both concurrently '73-'76, small pattern w/frt. drums & large pattern w/frt. discs.
-
