I need to replace the input shaft on a R380 gearbox. I know that I have to pull the box apart and remove the gear on the back of the layshaft, but do I have to disturb the gears on the rear of the mainshaft ?
I'm hoping that I can get sufficient movement by moving the layshaft forwards to allow the removal of the input shaft, does any one know if this will work ?

Not done any of above [ I am LT77 ] but I have R380 manual. It says layshaft, output shaft and selector shaft come out of casing as a unit. Then remove input shaft and 4th gear baulk ring if it did not come out with output shaft. Hope this helps. What is issue with your input shaft?

tottot said:

Not done any of above [ I am LT77 ] but I have R380 manual. It says layshaft, output shaft and selector shaft come out of casing as a unit. Then remove input shaft and 4th gear baulk ring if it did not come out with output shaft. Hope this helps. What is issue with your input shaft?

Click to expand...

Thanks for the reply, I'm trying to convert a TD5 R380 to a R380 Stumpy without destroying anything expensive.

Ah yes, going Defender mode.

It's over five years since I last had an R380 in pieces, but I don't recall it being too difficult. I put it bellhousing downwards (on blocks of wood so the input shaft wasn't touching the ground) and just undid all the bolts that hold the two parts of the case together - there's even a little hole in the rear part of the case so you can get a socket on some of them. They think of everything, these Rolls Royce engineers. There's also a detent peg that needs to come out - it's on a small oval plate on the top of the box, usually hidden by the selector mechanism, but when you take this off it should be pretty obvious. Then the internal mechanism can all be lifted out in one piece, as it's attached to the centre sandwich plate. In my case I laid it on a clean surface and then you can dismantle as much or as little as you like. I didn't take any pictures sadly so I can't show you.

Thanks for your replies, it's in bits at the moment, just awaiting a couple of bearings. I managed to remove the input pinion without moving the mainshaft, but only time will tell if I have to dismantle it further to re-fit the pinion.

Rougharse Racing said:

Thanks for your replies, it's in bits at the moment, just awaiting a couple of bearings. I managed to remove the input pinion without moving the mainshaft, but only time will tell if I have to dismantle it further to re-fit the pinion.

Click to expand...

Yes, might as well change the bearings whilst you've got it apart. Hope the gears are looking good and not starting to resemble circular saws!