My Son's girlfriend's Baja is jumping out of 4th gear. the gearbox is out of a 1971 Superbug. He was having problems with a dead spot in a Holley bugspray Carby, which He fixed... made the engine go like Turbo boosted... trying to accelerate as soon as the throttle was touched.....
Went extremely well .. but couldn't just drive it in 4th gear at the same speed... it was Go & Whoa.... So He thinks that was what caused the problem with 4th gear jumping out...
Is it easier to change gearboxes or fix the 4th gear???
:o:o:bounce

get yourself a good 2nd hand box.....much cheaper than fixing it. Keep the old one though, could be good in parts and be worth fixing one day.