Garagistic M30 Swap Guide- Shifter Mechanism


You have many choices here with the shifter mechanism. This depends on the transmission you get. In this section, I’ll denote these two designations as “Plate Style” Shifter mechanism and a “Rod Style” Shifter mechanism. I will discuss both types of shortening. Since I got this specific E28 transmission, I had to use the plate style shifter. It’s simply different hookups on the transmission itself. I’m going to cover the way I did it, and I think it was the harder of the two, so that should benefit anybody reading this.

I used the plate shifter method. I had to shorten and weld NOT ONLY the shifter plate, but also the shifter selector arm. This was very tricky because I had to feel how long to make it. Word to the wise: Do this after the engine/tranny has been dropped in. I can’t imagine how you would do it without any frame of reference. I’m not going to tell you exactly how much to shorten it, but I can probably ballpark it to be about 2 inches shorter. Every car is slightly different, especially since each engine sits at a different length.

See below for the realoem snapshots of both the plate style shifter and the rod style shifter.

As you can see in Figure 64 , Figure 65, and Figure 66, you need to shorten both the selector rod & the plate/Rod.

1. Cut the plate/rod in half (width wise), not length wise. Remember you’re shortening it.

2. Have a friend sit in the driver seat. You under the car with both halves. Attach the one half to the transmission via the two hex bolts. Forget about the shift rod for now. Line up the other half of the plate overlapping the first half. There will be about an inch or two (depending on engine position) of your shifter plate. Have your friend in the driver seat tell you when the shifter would be in the center of the hole. Then, make a mark, take it apart. And weld it together. I bolted them first, then I welded.

3. Now for the selector rod. This is very important how you do this because if it’s not right, you will have problems shifting and you’ll rip your shift boot.

a. Too short – 2nd and 4th gear will hit the center console

b. Too long – 1st, 3rd, 5th gear will hit the center console

c. Just right, the neutral position of the shifter will be right in the middle of the console and all gears will shift perfectly, including reverse.

I replaced all nylon bushings. They are yellow and look like thin plastic washers. I replaced 4 of them. It was tight, but then again, tight is good. It means minimal play in the shifter. I also used AND highly recommend a short shift kit to prevent any scraping of the shifter in the console, ruining my shift boot. 40% reduced throw, so I was happy.

Now in order to retain the shifter mechanism to the frame of the E30, you must think smartly about it, lol. The first iteration of this, I had no rubber bushing in between the shifter mechanism and the body (highlighted by Yellow circle in first picture) . I bolted it tight! Bad idea. Turns out that under coasting conditions, I could shift fine, but hard acceleration or turning situations I forgot that the tranny/engine DO MOVE, so having the shifter bolted to the frame was a bad idea. That’s why I decided to put a rubber bushing (Item # 15 in Figure 63). That allows about ¼” to ½” of play for the tranny to move around under hard acceleration. Now I can easily shift under any circumstances. I will leave this to your imagination. It’s not difficult if you can be creative and have a lowes or homedepot near you. I initially ruled out using the actual BMW part. I just didn’t think it would be compatible, but it most definitely could be.

In retrospect, you can weld/fabricate your own shifter mount/mechanism however you like. You will definitely need a stock selector arm and shorten it. There’s no question about that. That is simply a cut, shorten, and re-weld application. This is a pivotal step though because the length of this selector arm dictates the position of the shift knob when in neutral. You want it completely centered.

For reference, I’ve attached a picture of the Rod Style Shifter, including nylon bushings in Figure 67. I tried to find a picture of the connection points for the plate style shifter and the best I could come up with in Figure 68.

Above in Figure 68 shows the M30 Transmission that uses the sheet-metal style shifter. As you can see there are 2 13mm bolts that screw the plate shifter into the transmission. However, if you look at Figure 69, you will effectively see that the alternative is just as easy to install.

N/A TIME & $$ .2Hrs & $17 INSTRUCTIONS

You have the option to upgrade your shifter bushings to Delrin bushings by Garagistic.

Figure 70 shows the bushings and how useful they can be to enhance your ride. You can even get a rear