TD42 fourth gear synchro problem
Hi all, I have just had the oil in my gearbox changed/replaced and now I have difficulty changing from fifth to fourth gear. I have checked that the oil the mechanic used was the right one, (Penrite 80 90) Pro gear. Also for the first 1000 KlM's it would not go into fourth gear without "snicking" but that seems to have fixed itself. The gearbox was fine before the oil change and I am confused as to why only an oil change can have such an effect on synchro and gear changing. My question is will it rectify itself or am I looking at a re-con gearbox down the road. the gearbox has about 320000 KLM's on it, any advice would be greatly appreciated.