Auto Parts: BMW E28 rear sub frame bushing problem, bmw e28, alloy rim

Question
Mike,

My beloved '87 BMW, 535is has lost the sheet metal around the rear sub-frame bushing mount points due to rust. In retrospect, I believe the cause was a leaky rear window seal causing a chronically wet trunk. The water ran to rim around those inverted cups that locate the bushings, sat there and, voila!

The problem finally became obvious when one of the bushings totally separated and the banging started under heavy load and the torque steer kicked in.

The bushing pins and cross sections the pins mount to are in good enough shape, but the formed sheet metal sites that served as locating "cups" for the bushings are shot on both side. They are simply gone.

Have you ever heard of a fix kit or procedure for this problem? I believe it would involve sections of stamped sheet metal to replace the sections involved, the area being a square, about three to four inches on a side. Perhaps they might manufacture such a kit in Europe where these sedans are/were very common.

I am already aware that this is probably not going to be inexpensive. When I consider costs I compare it to owning and insuring a new 535is equivalent. I have an excellent mechanic who enjoys a challenge and loves this car almost as much as I do, but he has never run onto this problem in an E28 before. We are both pursuing solutions.

The vehicle is generally in excellent shape with recent investment in new winter and summer rubber on separate alloy rim sets (useless on more modern vehicles), new front and rear glass, recently replaced bottom end on engine (that's another story), updated air conditioning system, the usual front end rebuild on an E28, etc., etc. It's a fussed over car. If I retire it now, I get blown out of the water.

Thanks for any help you can lend.

Regards,

Rick Melloh

Answer
    For a good body man, this is a relatively easy problem to solve.  He cuts the needed parts out of a wrecked car and welds them into your car in place of the old sheet metal.  I hope you are not driving the car in the mean time, it's dangerous.  You probably won't be able to get this done at a dealer body shop or even a big independent operator.  But there are guys out there who will do it.  I had a similar problem on an XJ12C and my body guy just cut out the old piece and fabricated a new one from sheet metal.  I could have bought new sheet metal from Jaguar but it involved such a big piece of the unibody that we decided to go the other way.  This kind of fabrication is common on street rods, so you might look for hot rods parked outside of a shop as an indication of who can do what.