Rear Backing Plate

PC/SR

Well-known member
Am working on the brakes. The nut on the rear backing plate bolt bottoms out on the shoulder of the bolt. It is "snug" but not "tight" if that makes sense. The plate is not loose and does not rattle around, but it would take maybe a quarter turn more to be really tight. Is this correct? Am I missing something? Use a washer? Thanks
 
It sounds like the grease catcher has worn out holes from being used with loose bolts. If so you could find a better grease shield or just use a flat washer to take up the space.
 
I have seen this problem over the years and have never seen a satisfactory answer to the reason for it. Therefore I developed a method of dealing with it.

The first time I ran into this problem all four bolts on both sides had bottomed out and it allowed the backing plate to rock back and forth during braking and acceleration and ruined the backing plates as all the bolt holes were worn oblong.

There is a technical article on how to deal with it. Go to the web site of the Santa Anita A's of Arcadia, California at santaanitaas.org. On the home page put you cursor on "Technical Reference", my name will appear below, click on it. A menu of articles will come up, Scroll to "Rear Backing Plates" and click. The article is a pdf file. You are welcome to download it and print it out.

Tom Endy
 
I concur this is a decent fix as long as the baffle is in decent shape and will hold tight as well. I have also used lock washers from time to time behind the nut ( they must fit tighly and go in to the hole of the baffle. They tighten well and hold the baffle snuggly which is a plus. It is imperative that all backing plate bolts front and back be very tight.
Larry Shepard
 
I have used spacers on the bolt under the head to take up the difference, the shoulder of the nut needs fit the grease shield. A lock washer would likely be too large OD to fit without distorting the shield.

A's Always
Dave
 
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