You can rebuild your e15t box with n13 internals!
1 st get n13 box...then the crown wheel(4.11:1)unbolts off the n13
diff and bolts straght on to the ET diff(still using ET
Take the crown wheel from your n13 gearbox, and put it on your n12 diff.
You'll find that the n13 diff just won't sit and spin in the n12
bellhousing, which is why we reuse the n12 one, but with the appropriate
You need to do this so that the final gear on the output shaft of the
n13 gearset matches it's original counterpart, the crown wheel.
> i also know that the gear train needs to be swaped over...but am
> unsure of if it is a straight swap....
Pull everything that is n12 related out of your existing gearbox,
hanging onto the diff.
Keep the bellhousing part of the gearbox, aka the bit that bolts to the
engine, you don't need the cover that goes over all the gears
You then take the n13 input shaft, and put it in the n12 bellhousing,
likewise with the output shaft. Keep the n13 selectors with the n13
Now, SWAP THE SELECTOR SHAFT.
This is very important. Additionally, I found I even had to swap the
reverse gear section that bolts through the side of the bellhousing on
into the side of the input shaft.
It's an ass to get out, you'll need a really big headed phillips
screwdriver to get them out.
So take this out of the n13 bellhousing, and put it in your n12
bellhousing, along with the n13 selector.
To remove the selector, it's actually in two pieces, you'll need to
knock out the split pins (2, one inside the other) about half way down
the selector - then you can get each half out.
Basically everything gets swapped over. Oh with one nasty exception -
the speedo drive, you use your original speedo drive BECAUSE the speedo pickup is *after* all
the gear ratios, it's going at wheelspeed, not 'diff speed' hence no
matter what gearset you have in there, the speedo is still spinning at
the same speed as your wheels, so you don't use the n13 one. Another
trap for the unlucky amoungst us.
The dog selector gear has teeth on both sides of it. These are
what crunch when you don't fully engage gears. They are all made the
same, even the one that engages 5th gear. This means one side isn't
used. So, when doing the re-assembly, this gear can be popped off
and swapped end for end giving brand new never used teeth to mesh
with. Just be a little careful as there are 3 locating pins which
are spring loaded, these need to be pushed into place to allow the
dog gear back on the shaft.