Hi, had a weird issue with 2 driveshafts last Thursday, on the way to Silverstone (shaft number 1) and on track (shaft number 2).   Basically on the way there I stopped to fuel up to fine gear oil pissing out of the offside gearbox seal.   Limped it to the garages at Silverstone to find this:     The collar had come loose, allowing the bearing to slide down the shaft, and the shaft to pull out of the box.   So put my 1st spare shaft in, filled up with oil, took it out for a couple of laps, and lost all drive! Same thing happened to the spare shaft only this time it came out so far the splines were no longer in the diff!    We had one shaft left, so put it in and gave it a hammering (wheel spin, full lock) outside the track, and all seemed well. Went out and spent the whole afternoon on the track with no further issues.   Checked with Miles and he said that it’s very unusual but some of the rally guys weld on the collars to stop this happening, so just put it down to bad luck and a poor tolerance fit on the bearing retaining collars on both shafts. Both collars have been moved previously (after failed wishbone and a crash).   Yesterday I took a look at the shafts and drifted the collars back on, but it took a lot of force (tube over the shaft and a lump hammer), so now I’m a bit stumped as to how / why the collar came loose.    Immediate thoughts were:   - Problem with Gripper diff - cross pins moving / knocking the shaft out. - Problem with Diff bearings - diff moving left right and hammering the shaft out.   But, took the speedo housing off and there’s no sign of this - no movement of the diff, and the diff is operating well. Plus you would have thought the other shaft would have also been knocked out given that’s only held in place with a spring...|

  3rd shaft has been fine since, so shall I just get the collard tack welded in place and forget about it?    Anyone else had anything like this happen?