Triumph Repair: Prop shaft alignment, shaft alignment, diagonal measurements

Question
Jim , first you may recall you gave us advice (all good) about removing the tub. Well its off. We braced between the door openings using the door latch and hinge nuts to secure it. This prevents the tub buckling and is also an excellent lifting point for 4 people who can easily carry it. However to turn it over to work on the bottom needs six so you dont put the windscreen on the ground. Its now supported on two pillars at the front and a saw horse in the boot.
Now the question. Its an overdrive model with gearshift switch. Looking from the rear the engine/gearbox appears slightly angled towards the drivers side and the prop shaft in the other direction towards the diff. The gearbox overdrive unit appears mounted slightly towards the drivers side. I can find no evidence that the chassis frame is bent, diagonal measurements are equal. Whats going on?
Thanks for your help.
Roger6v8tn

Answer
Roger and Chris,

While you've got everything apart it's not a bad time to check the frame for straightness.  The Bentley manual has a diagram showing alignment points and dimensions for the frame.  Some versions of the Haynes manual also include that diagram, although looking in my collection I see that not all versions of the Haynes manual seem to.

And yes, the drivetrain does sit a bit diagonal in the frame.  If you look at the differential, it's mounted "centered" so the axles are equal length.  But the driveshaft mounting flange is not centered on the differential.  

So that's what's going on.



Cheers,

Jim