Hi all I am haveing big problems with my p38 it was a 4.0 but engine went tits up so found a genuine 4.6 landrover exchange unit so. Had it fitted at a garage car started first time idel good sounds really sweet they took it for a test drive everything ok then when stopped at junction went to set of no drive came up gearbox fault so had it recoverd back to garage left it over night still no drive no gearbox fault message not displayed any more still no drive on dash it says in in gear and when you move gear selector it says you in relivent gear but still no drive it revs fine and runs smooth any ideas please I don't know where to turn