M35a2 Brake Shoe Anchor Pins and Major Adjustment Problems

[Lieutenant Dan]

Ok so I got my rear all back together today re packed bearings and the whole 9.... brake shoes are like brand new or all but......

So I followed the tm on major and minor brake adjustment. The right side went beautiful with .010" on the bottom and .020" on top. Backed off till no drag.

Now the right side was a different story. The bottom adjusters seem to push the shoe up and makes it tight at the top not the bottom on both shoes. I tried clockwise and counter clockwise tighten the top first then the bottom and tried them evenly. The best I could do was .035 " at the bottom which puts the top at almost completely bottomed out with zero adjustment meaning they are completely loose. I got it set nicely with no drag but I don't like the bottom gap cause its going to wear the shoes funny. I can't see why this is doing this. The anchor pins where fine and I put the punch mark showing the high spot towards each other so they would adjust correctly.

Any help on this? I'm probably going to have to pull it all back apart again just because I can't figure out why it's doing this. It just sucks since I got it all fresh grease and cleaned and rtv and corked the key ways. Man it makes me furious.

 

[gimpyrobb]

For future brake jobs, I have found that .015 top and bottom works great. Did you turn the bottom adjuster all the way around? It should make the shoe go up, left, down, right. Not sure the issue there.

 

[Lieutenant Dan]

Yeah robe kept spinning them and spinning them in both directions clock wise and counter clockwise and the top would get tight and that was it. You could see the shoe moving up and down but it never got closer then .035" to the bottom but

 

[Lieutenant Dan]

And there is nothing in the tm about this situation either

 

[gimpyrobb]

Is this one of the "not new" shoes? Maybe it was previously adjusted wrong and now you have a (non adjustable)gap?

 

[Lieutenant Dan]

No they are both like brand new on both shoes and both sides of the axle. They measure .498" on all shoes measuring anywhere on the shoe.

 

[gimpyrobb]

It would suck, but those adjusters come off. Might be due for an inspection.

 

[Lieutenant Dan]

I just did the entire brake system that's what I don't understand

 

[gimpyrobb]

Did you take the bottom adjusting cams off the backing plate? Thats what I was suggesting.

 

[Lieutenant Dan]

No I didn't do that

 

[welldigger]

I have dealt with this on several trucks. I hope you find an answer cause I just adjusted them the best I could and moved on.

 

[Lieutenant Dan]

I'm seriously thinking about it.....

 

[Lieutenant Dan]

How close did you get yours welldigger?

 

[DieselBob]

I would suspect 3 things. Worn anchor pins, slightly over size mounting hole on the brake shoe and my number one thought that the brake drums are past the max diameter spec. Add all three together and you will never get the adjustment correct. Just my

 

[Lieutenant Dan]

Idk about the shoes being worn but I guess so and the drum didn't have any lip so I can't see it being worn to much. If it was to big why does the tip get so tight with only the bottom adjusters

 

[gimpyrobb]

Ha, I never thought about that. The tops and the bottoms are related. Adjusting one affects the other. Have you tried adjusting them multiple times? Try going back and forth top and bottom and see if it helps.

 

[welldigger]

I think the worst one I did was .03 on bottom and .015 on top. That was as close as I could get it without one end of the shoe dragging the drum. This was with new shoes.

 

[Lieutenant Dan]

Yup. I'm thinking the anchor pins are messed up.... I'll have to wait to get it apart and see.

Welldigger mine were .035" on the bottom but the top touches big time. It get so tight with very little adjustment that I can't spin the tire with everything I have.

 

[welldigger]

I did not remove the bottom adjusters since I had to adjust all 6 and get the truck on the road. Since I'm starting the tear down of my truck next week I think I'm going to pull my adjusters completely apart and see if I can figure out what exactly is going on.

 

[welldigger]

Yup. I'm thinking the anchor pins are messed up.... I'll have to wait to get it apart and see.

Welldigger mine were .035" on the bottom but the top touches big time. It get so tight with very little adjustment that I can't spin the tire with everything I have.

Yup pretty much what I went through on no less than 2 trucks. And to some extent on an a3.