hi i have a 1996 2.8TD mitsubishi challenger and over the last few days an A/T warning light has been flashing on my dashboard this will happen for about 30 seconds and then goes off it tends to be when the engine is wwarming up it has only happened twice but it has got me worried in case it is the gear box or somthing that is going to be a big and expensive job can someone please help me with this problem