Ok i have a 1999 expedition awd-4wheel drive-4wheel low. the truck was stuck in 4low brought it to the shop they put in a new moduel and a new pump in the transfer case, now the truck is stuck in 4 high i bring it back and they tell me im imagianing it! wtf.. i know it is stuck in 4 high when i turn the corners the front tires go chirp chirp chirp, and the thing is killing gas now. what should i do?