The prop shaft has to be installed before the differential, so it was next on my list. I didn’t expect this part of the build to warrant a post, but I decided it was worth a mention, because it wasn’t as easy as expected (for this build anyway).
Prop shaft as delivered Prop shaft grease nipple Grease gun
The first thing worth mentioning is the grease-nipple on both universal joints. I wanted to start as I mean to carry on, so I decided to get the grease gun out and top up the lubrication. It’s full of Castrol Multipurpose (LM), which is lithium based.
BMW spline grease Smear of oil on the shaft
I applied a small amount of BMW spline grease into the prop spline, and applied a smear of oil on the shaft to protect the gearbox oil seal during insertion.

I assumed I might get a few drips of gearbox oil when the bung was removed, so I wrapped a lid in a bin bag as a temporary drip tray. I used side cutters to remove the tie wrap and pulled the bung is out from the gearbox.
Now I am not sure why, but for some reason the front universal joint of the prop shaft was wider than the transmission tunnel, not all the way down, just the cut-outs / recesses for the seat belts, and not by much. The problem was limited to about one inch and the solution was to push it through with a simple tap of my hand, but this removed paint from the universal joint and the aluminium cut-out skin. It was one of those moments when you have to decide between do (and cause damage) or don’t (and the car won’t be built). Now, I am keen to look after my car as best as I can, but at the end of a day it’s not a show car – I want to drive it, so it will never be “perfect”.
What’s strange is, that I don’t remember this from my last build, but the 360R had a 6-speed gearbox, so maybe the universal joint may have been smaller, or this is a tolerance issue with the seat belt cuts-outs.
Prop shaft installed Looking down the transmission tunnel
Still nothing that POR15 chassis paint couldn’t sort, so this is just a warning for future builders.
Tool Used
- Grease gun
- Side cutters