I've got a 9.25 rear from behind an early 80s van. laying around. its got huge rear drums. Anyone know if these will fit on a 8.75 ? Or should I even think about it? :burnout:
rear brake question
- Thread starter dukeboy440
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if its 5 on 4-1/2 they will most likely fit.
Probably 11" drums and 2-1/2 or 3" wide shoes.
Pretty much all the 65 and up non-small bolt brakes will interchange as a complete unit. 7-1/4, 8-1/4, 8-3/4, 9-1/4, DANA.
Some earlier and smaller rear backing plates will only have 4 mounting holes. Just drill for the fifth!
Probably 11" drums and 2-1/2 or 3" wide shoes.
Pretty much all the 65 and up non-small bolt brakes will interchange as a complete unit. 7-1/4, 8-1/4, 8-3/4, 9-1/4, DANA.
Some earlier and smaller rear backing plates will only have 4 mounting holes. Just drill for the fifth!
Sweet. They are 11 inch and 3 inch wide shoes. Figured may as well re-use the good stuff. Eventually i'll be going to disc brakes but for now, these will do. Thanks Jim
chryslerfat
Well-Known Member
Is this a floating axle rear with 8 studs ?
No, its a 5 lug, not sure of the pattern but I'm pretty sure its 5x4.5 as the rims that came off of it I used on my 74 Charger when i had it
nm9stheham
Well-Known Member
You may throw you brake proportioning all out of whack with this big increase in drum diameter and surface area; it might work or it might not; from what I have read, the police option brakes on B-bodies was 11"x3" drums. BUT, the brake size was changed both front and rear with this option to keep the right proportioning.
Impossible to tell without knowing the diameter of wheel cylinders versus your original ones, and what you have up front. What year car is this going on and what was the year of the van? Maybe we can look it up. I am only seeing 12" x3" for 1982 B150 vans; the 11" shows only in 2.5" width. They do show quite a variety of rear wheel cylinder sizs from 7/8" to 1-1/16" diameter for the 12"x3".
Too big a rear brake will cause premature rear brake lockup; that's bad juju on a wet road or even on a dry road at high speed in a panic situation ==> spinout.
Impossible to tell without knowing the diameter of wheel cylinders versus your original ones, and what you have up front. What year car is this going on and what was the year of the van? Maybe we can look it up. I am only seeing 12" x3" for 1982 B150 vans; the 11" shows only in 2.5" width. They do show quite a variety of rear wheel cylinder sizs from 7/8" to 1-1/16" diameter for the 12"x3".
Too big a rear brake will cause premature rear brake lockup; that's bad juju on a wet road or even on a dry road at high speed in a panic situation ==> spinout.
I added 11x2.5" brakes to the back of my Challenger and paired them with the 11.75" rotors from the later cars. Using the stock prop valve everything is pretty well balanced.
I also use the 11x2.5" drums on my Duster, but I have Dr Diff's 13" Cobra rotor kit on the front. Again, stock prop valve, and again, pretty well balanced with the rears not locking up before the fronts.
The 11x3" drums should fit on your 8 3/4 just fine. You may need to experiment with the wheel cylinder size if you keep the stock front brakes and prop valve, there are a couple different rear wheel cylinder sizes that came on the 11" rear drums, both 7/8" and 15/16" were pretty common depending on the model.
I also use the 11x2.5" drums on my Duster, but I have Dr Diff's 13" Cobra rotor kit on the front. Again, stock prop valve, and again, pretty well balanced with the rears not locking up before the fronts.
The 11x3" drums should fit on your 8 3/4 just fine. You may need to experiment with the wheel cylinder size if you keep the stock front brakes and prop valve, there are a couple different rear wheel cylinder sizes that came on the 11" rear drums, both 7/8" and 15/16" were pretty common depending on the model.
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