transmission u0101, p0700, p0098
 

I have a ford focus 1.6 tdci 56 plate automatic, when in lower revs (1k - 1.5k revs) it slips into what feels like 2nd gear and doesnt change, i can turn the engine off and back on again and re-sets it so i can use normally until a few minutes later when revs get low it happens again,until today, i could hear the fan on and very loud, and the car struggles to build up speed after about 5 minutes of driving it, it shows fault codes u0101 - p0700 - and p0098 and i have also noticed some oil coming out at the bottom left when driven where the gearbox is, so i have parked it up and now not using it, do you think it will need another gearbox or as 2 of the 3 faults are to do with the tcm i can get one out of the scrappy and just change it? I dont know alot about cars but any help would be appreciated, Thanks

I think u0101 - no communication with tcm p0700 - short or open curcuit within tcm and p0098 - intake air temperature sensor 2