Mushy brakes 4 life...

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If you have a soft pedal, Def flex brake lines, Def master cylinder or out of adjust shoes or AIR in the system. To bleed out the air in the MC, just mount it in the car, leave the lines off, use the little red nipples and clear tubing, and use the brake peddle to bleed it. Put shop towels under it to catch drips, when no more bubbles, remove the nipples, and screw on the lines, clean up any drips, there wont be many, and refill MC, all done. EZ PeeZe. Brakes are not that difficult IMO.

Have you seen the pics above? Air in the line is about #6 on the list.
 
If you did not bleed the Mc separately, there is a high chance there is air in the system, plain and simple.
 
there seems to be other things going on with the rear brakes, but I dont think that is the end of the problem,
 
The drum is so far on the shoes are expanding over in the non friction surface area. You can see the shoe contact area is like 1/4”. Then I’m sure they **** in there. I think I need to sort the hardware end of this before I restart the hydraulic part of it. I need to get the shoes where they belong. Ugh. I wonder if these are some sort of truck drums or something dumb like that.
 
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If somebody has an 11x2.5 drum and can measure it like above that would be a big help. That might eliminate or confirm the problem. I just hate to go spend money on drums if that’s not the problem.
 
Are the drums china repops? On my Dart, I had to have a machinist shave about 1/8 inch off my drums. I know you can't do that, since it's hitting ing the groove on the drum, but maybe off the backing plate, if you have no other options. Also, look for slight leaks from the wheel cylinders. I had a new Oreillys that you could see leaking by pulling the wheel cylinder boot back.
 
They are Chrysler OEM. For what it’s worth... RockAuto has an 11” drum that measures 4.23” overall “height”. Where I am at 4.5. That 1/4 would seem to be to be what I need. Now... they don’t list if that’s a 2 or 2.5” drum. I’m not taking a guess chance though.
 
I found another Raybestos reference that shows 4.47” flange depth to inward face depth... which is pretty much what I have. It’s now seeming like I have a weird backing plate. I’m not opposed to grinding back the backing plate but I’d like to find the answer. I guess in the past I’ve been lucky to find complete donors and I knew exactly what I had and it was already working.
 
I agree with you about the narrow pad contact area. It looks like they are rocking, contacting too far into the drum in the un machined area first.

This is not the first post about drums contacting the backing plate after installing green bearings. I wonder if it is a housing problem, if the bearing cavities in the housing ends are either machined too deep from the factory, or if that housing suffered a bearing failure at one time and the failed bearing wore the housing. With the original tapered wheel bearings adjusted to proper clearances the problem likely would not be apparent.

Perhaps pull the axles and put some spacers (1/8"??) In the housing ends before putting the axles back in? This would space the axles and therefore drums outboard enough to clear the backing plates and allow the pads to contact the drums where they are meant to.
 
Or as another thought, the retaining ring groove could be in the wrong location on the bearings? Or the area where the retainer seats is worn?
 
Axle housing looked very very nice. The green bearings have snap rings so you would have to destroy the snap ring to go to deep. DrDiff aka Cass was very helpful and gave me a backing plate to axle flange measurement. He said 2.4”. I’m right at 2.4. So the axle depth spec is on the money. I’ve got new drums coming just to make sure I don’t have some weird truck drum or something going on there.
 
Dude, You've got a cluster-duck there, & I'm afraid the wrong backing plates. But I'll post these dimensions for You, & You can verify this to see;
1) For the 11X2.5" shoes
A) Backing Plate outer face of axle tube mount to Brake Shoe Seating Pads-----1.125" (1 1/8")
B) Shoe Seating Pads to Backing Plate Outward Facing Edge------.09375" (3/32")
C) Shoe Seating Pads to Back-side(Inner) face of Anchor Pin "Wing Plate"-------1.50"(1 1/2")

2) For the "other" 11" Backing Plates I have
A) .9375" (15/16")
B) .250" (1/4")
c) 1.3125" (1 5/16")

I believe You have the second (wrong) set of backing plates...................................
 
I measured last night. Axle flange to brake pads both sides. Measured the axle flange surface of the drum to friction surface. They are dead on. In other words the shoes and shoe surface of the drums are in perfect alignment. It’s just the damn lip of the backing plate and drum interference. I don’t think I could put a 2.5” pad on an 11x2 backing plate and it even be close. Thanks for the measurements. I’ll take one side apart and measure it.
 
I measured last night. Axle flange to brake pads both sides. Measured the axle flange surface of the drum to friction surface. They are dead on. In other words the shoes and shoe surface of the drums are in perfect alignment. It’s just the damn lip of the backing plate and drum interference. I don’t think I could put a 2.5” pad on an 11x2 backing plate and it even be close. Thanks for the measurements. I’ll take one side apart and measure it.
The friction surface in the drum is 3" wide, the shoes are only 2.5", there should be approx. 1/4" gap from each edge to the edge of the linings,......is that the case??
 
I believe ,you have early C body brake, backing plates, they use thinner shoes than the later brakes. That is the reason the shoes are cocked on the pin.
 
The friction surface in the drum is 3" wide, the shoes are only 2.5", there should be approx. 1/4" gap from each edge to the edge of the linings,......is that the case??
Yeah math shows the shoes will be right in the middle of the friction surface.
 
I believe ,you have early C body brake, backing plates, they use thinner shoes than the later brakes. That is the reason the shoes are cocked on the pin.
The shoes are cocked from where I pulled off the drum without backing the adjuster off. They are flush easily by hand. As mentioned above.
 
For what it’s worth you can tell these backing plates were married to this axle housing. Just the rust spots and grease on one side etc. and this is a B body axle. So I have to believe they are B body plates. I wish I had a set of 11x2.5 plates that I knew were correct just to damn try. Ugh.
 
For what it’s worth you can tell these backing plates were married to this axle housing. Just the rust spots and grease on one side etc. and this is a B body axle. So I have to believe they are B body plates. I wish I had a set of 11x2.5 plates that I knew were correct just to damn try. Ugh.
If I get a chance, I'll see if i can expose some part# stampings on these, but the dimensions I gave show the amount of diff being about 3/16-~1/4" of offset, w/the "other"
out towards the drum. I put a '68 RoadRunner 8.75 in My ex-cop Dippy, left the brakes,lines,cables, everything hooked up to the car, just yanked the axles & unbolted 'em
w/o havin to so much as re-adjust or bleed anything, drums went right on. The BP's I gave dimensions as 2.5" are the same as those. Still have that rear but it's not close.
As far as bleeding, I don't bench-bleed anything anymore, but You do need to bleed the master at the lines after the fluid runs out the ports good. Otherwise, unless a cal.
piston or wheel cyl. piston is over-retracting, I'd say the way those shoes are touching they are not square in there at all, & there is a lot of lost travel trying to put them
there.
 
I’m positive the “brake drag” I felt to adjust the drums was really the backing plates rubbing. I think the shoes were miles from the drum in reality. I think once I fix the backing plate clearance issue, and run the shoes out... I’ll be good to go. I hope and think.
 
I’m positive the “brake drag” I felt to adjust the drums was really the backing plates rubbing. I think the shoes were miles from the drum in reality. I think once I fix the backing plate clearance issue, and run the shoes out... I’ll be good to go. I hope and think.
LOL, I hear that, frustrating for sure....
It looks like that backing plate took a little "real world" abuse service-wise over the years, not uncommon, may need a little TLC massage here & there. BTW, a lot of the
aftermarket stuff doesn't come finish machined to spec, every single pre-owned Tundra done for the dealership My co-worker & I have had to machine the park drum
section "lip" of the rear rotors down at least 1/8" to prevent them from rubbing the backing plates before installing them. I prefer OE Toyota ones, but the $$$ & how deep
they are in the deal usually dictates which ones go on.................
 
They were mint before I machined them with the drum! 2000’ of driving it clearanced them! I thought we had them spaced but I guess a little play and they machined themselves. Ugh.
 
The rust transfer from the drum to the shoe is telling you a story.
And I'm not sure about the drums either; I have never seen a drum that wasn't machined right out to very edge. Yours appears to have a deep lip, and the only time I have seen that was with worn out drums.
 
I'm not even too damn sure you have the correct diameter backing plates at this point. Somehow I missed those photos earlier. "How do you know" what you have, ANY of it? I can see the shoes, you bought them, and the hardware. But the backing plate and drums may be completely unknown??

The way the shoes are cocked seems to me the drum is not going on far enough, not too far. As I said earlier, IF IF it was a simple matter of the drum/ backing plate interferance, you could have the rear edge of the drum taken off in a brake lathe. I don't think that is the "only" issue(s)

Cam you seat the shoes on the backing plate and "see" that they actually fit that much OK?
 
I have never seen shoes flip up like that unless they were too wide, or the backing plates were in the wrong plane. If the pushrods from the W/Cs are in any position but parallel to the centerline of the car, then you have a mismatch of parts, that has nothing to do with the axles..........yet.
If the shoes flip up by themselves......something is wrong, and they will flip up after the drum is on, and SHAZZAM there is your mushiness.
 
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