Rebuilt R380 gearbox crunches going from first to second with revs

So I've just had the R380 gearbox for my 1995 Defender 110 rebuilt and refurbished. Everything feels great except when changing from first to second - it almost always crunches.

Third to second is fine and every other gear change is fine.

If I double clutch from first to second it doesn't do it. If I hold down the clutch, then slowly slip it into netural, let the revs slow a bit and then go for second it's OK.

But that's not how any normal person drives a car and it's certainly no good going up hill as I lose too many revs in the hesitation.

I've contacted the people who just rebuilt the gearbox and they tested it and it did it to them too, but they said to leave it for a while, let it settle down and if it doesn't go away to go back to them.

Any ideas what's going on? Is this common for a refurb/rebuild and do I need to be worried?

new baulk rings may run in ,but you may have faulty one on second ,if it doesnt seem to be improving they will have to fit another one, have you got the right oil in dexron 2or 3 (atf)or mtf as this will effect baulk rings and give poor change especially 2nd as it has the hardest work during gear change ,baulk rings are cone shaped rings that run on gear cone the synchro hub pushing them ,should allow the friction between them to bring gear speed to synchro hub speed allowing hub to slide over on to gear dog teeth,its more common for new baulk rings to jam on making gear stick hard to push into gear ,worn baulk rings grip gear cone and so not matching gear speed to synchro speed making it crate as you try to engage gear

Well as the Transmission place sorted out the rebuild I assume they've also sorted out the required oils. Is that an incorrect assumption to make?

I'll run it in for a week and see how it goes. It's just really frustrating as it's been out of action for the past 3 weeks and now I get it back I can't drive it 'properly'.

who did it? Give ashcroft transmissions a call, they are usually helpful on the phone

My guess is its been filled with the wrong oil.

After having a new clutch fitted, mine crunched badly from 1st to 2nd. I had to have the box sent off for a new synchro mesh to be fitted. Still not perfect, but much better than it was.

Interesting. I also just had a new clutch fitted.

Perhaps something in the clutch needs adjusting?