howto replace rear brake backing plate on 1988 325i? - BMW Forum

lortech · 06-08-2009, 05:38 PM

Its not often I work on BMW's But in this case, the rear backing plate that secures the rear brake emergency shoes with the hold down springs has corroded holes in the backing/splash shield plate. So the spring holes are much to large and thus, the rear backing plate needs to be replaced.

It looks like the rear hub has to come off in order to remove and replace the plate. Now I need a rear hub slide hammer to take this off? Does the cv-joint axle shaft have to come out? Also, I think I will need to have a hub berring press kit to reinstall the hub? Your quick answer is much appriciated need to get this back together today.

Thanks

Loren

dannyb · 06-09-2009, 07:49 AM

easier fix for this, use "locking washers" from a drum brake kit. Needs a bit of modification but can be done in 5mins or less. Let me know if you have any questions

lortech · 06-09-2009, 12:12 PM

The plate needs to go on. seems no one has done this. And im out of time.

dannyb · 06-09-2009, 01:52 PM

You cant return it? I heard of a guy who cut the old ones and welded the new ones in place. Other than that you have to remove everything and most likely buy new bearings.

lortech · 06-09-2009, 02:15 PM

I dont think the owner will go that route. If i had a welder, I would do the same. These pieces should have been sold as a two piece unit where both pieces overlap and or rivit, bolt together the pieces.

So what are these clips you are talking about? I noticed there was one clip on the back. It was larger then the hole ?

dannyb · 06-09-2009, 02:20 PM

The four clips under the springs in the picture

I got mine off a cavalier, just needed to make the holes a bit bigger using a drill. The kit was like 6$, much nicer price compared to new backplates and all.

lortech · 06-09-2009, 02:41 PM

Seriously, they do not look like they will hold the pins. This bmw came with one clip, other is missing. So going to tell the owner to buy new clips. I will pick them up for him. Hope he has the reciept to return the backplate.

dannyb · 06-09-2009, 05:30 PM

not the horseshoe clips the round clip

silversled · 06-09-2009, 08:11 PM

so you are saying that you have a 1988 BMW 325i with drum brakes?
What country do you reside in?

dannyb · 06-09-2009, 08:25 PM

handbrake shoes are like drum brakes

lortech · 06-09-2009, 10:36 PM

and calipers are for regular brakes.

Anyway, I found a electrical junction box that had some sheet metal wings and modified its hole to accommodate the shoe hold down pins. It was a real time consuming ordeal not only in making them, but find the metal, then they would not stay in place. Finally, I got the pins to hold in them. I saved the onwer allot of money in pulling the bearings ect. BTW this bmw has corrosion. Sucks!! this is the reason why the splash plate has corrosion. Now the brake line is leaking. Corrosion has eaten it over its life and working on that brake has weaken it where it leaks. None of the lines can come off even with heat. I told the onwer if you want to flip cars, PLEASE do not buy one with corrosion it will eat you alive to in the terms of $$.

silversled · 06-11-2009, 07:44 PM

I guess it may be a matter of terms.. where I come from a backing plate is normally associated with drum brakes, on disc brakes we call it a dust plate. A backing plate is significantly more substantial than a dust plate....drum brakes are a mother to work on....but, technically, they are superior to discs.
Just a pain to maintain.....