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MM Short Shift Install - Long

Due to strong interest from fellow Digesters, below is the installation procedure I followed to install a 
Metric Mechanic short-shift kit in my ’87 535is.  My shifter was swimming all over the place, was inclined to 
come out of 1st gear just as I was pulling away from a stop, and would bump into the side of the console when 
going into reverse.  Replacing the stock bushings would tighten things up but I was interested in a shorter 
throw too.  I chose MM’s kit because it was the only one that replaced all the stock shift linkage components. 
 The AutoThority kit ($99) is a machined piece of metal that changes the fulcrum point of the shift to shorten 
throws.  It doesn’t address the tendency of the factory shift linkage bushings to wear out.  I bought the kit 
from BMP for $149 but it is available directly from MM for $140 ($170 for cars after 9/89).  You can reach MM 
at 2507 Truman Road, Kansas City, MO  64127 – 816-231-0604.

Before I get started I’d like to strongly recommend the Bentley service manual.  The included illustrations 
and instructions in it were extremely helpful in my installation.  You will need an assortment of 
screwdrivers, wrenches and metric sockets.  Replacing a number of lock nuts is also recommended but you won’t 
be able to get the right ones until you take the ones you are replacing off the car.  

The entire procedure took me 6-8 hours.  If I did it again it would probably take 3-4 hours.  In general you 
will be removing the exhaust system, disconnecting and removing the upper and lower shift lever, lowering the 
transmission/engine assembly a couple of inches, and replacing the shift rod assembly.  Then, of course, 
you’ll want to put all that stuff back together.

There are several steps to the install:

1.  You will first need to jack up the front end a good 1-2 feet.  Please use jack stands and wheel stops as I 
don’t want to feel responsible for something awful.

2.  Disconnect the exhaust system from the exhaust manifold.  You will need a long socket extension for this 
as access from above to accomplish this is very limited.  The locking nuts that you will be removing have been 
exposed to a lot of heat and will likely need a good bit of effort to break free.  Some Liquid Wrench or 
similar product may help.  Moving from front to back, the next attachment point for the exhaust system on a 
535 is a bracket attached to the transmission by two bolts.  Remove these.  (FWIW, 528s and 533s differ 
slightly from the 535 in how the exhaust system is supported.)  Now go to the back of the car and remove the 
bolt holding the muffler retaining ring (rubber suspension thing).  At this point the only things supporting 
the exhaust system are two retaining rings like the one at the muffler which are located forward of the 
differential.  I suggest supporting the exhaust with a floor jack prior to disconnecting these retaining 
rings.  Now lower the exhaust to the floor and push it over toward the passenger side of the car.  It will be 
supported by the muffler at the rear and by the sway bar at the front.  Remove the heat shield concealing the 
drive shaft center bearing  which is halfway between the transmission and differential.  There are 6-8 nuts 
and washers holding the shield to the car.

3.  Next we need to lower the transmission a couple of inches.  First reach up over the drive shaft and remove 
the circlip holding the shift rod to the lower shift lever.  Disconnect the shift rod from the lever.  Remove 
the two nuts holding the center bearing bracket to the car.  Use a coat hanger or similar stiff wire pulled 
tightly across where this bracket attached to the car to support the drive shaft for the next step.  Moving 
forward, support the transmission with a floor jack.  Remove the four nuts holding the transmission support 
bar to the car.  I also removed the two nuts holding this bar to the transmission so as to remove the bar and 
get it out of the way.  Lower the transmission/engine combination until it rests on the front crossmember.  At 
this point you should be able to reach up and over the drive shaft/transmission joint and touch the connection 
between the shift rod and transmission selector shaft.

4.  Now we remove the shift rod.  The socket on the rod slips over the transmission selector shaft and a pin 
drops through a hole in both.  This pin is held in place by a lockring which is open on one side.  Reaching up 
to the joint, rotate the ring until the opening in it faces the passenger seat.  Use a small slotted hobby 
screwdriver to lift the lower edge of the lockring.  Then use a long (1.5-2 feet) slotted screwdriver levered 
against the transmission to push the lockring toward the rear so it skirts back up on the rear of the socket 
assembly.  This may take a few attempts.  The pin will now be exposed and may even fall out by pushing forward 
on the shift rod.  If it doesn’t, use a stiff piece of wire to push it out.  Remove the shift rod. Transfer 
the lockring to the new shift rod and install this rod on the transmission.  Be sure the lockring opening is 
rotated to one side so as not to allow the pin to drop out.

5.  Take a break if you haven’t already done so.  By now you deserve one.

6.  Remove the old lower shift lever and install the new one from inside the car per the instructions from MM.

7.  Now reverse the above sequence and put everything back together.  It is recommended to replace any 
locknuts that have been removed.  

I am pleased with the results.  I know what gear I’m in now and I can find the gear I want.  The throws are 
also shorter which is a nice improvement.  I would definitely do it again.  Good luck with your own 
installation.