I have a 1998 isuzu rodeo 3.2 V6 DOHC 2wd.I had to replace the alternator and since that went out my transmission is acting up. My husband got under the car and checked the fluid and it was low so he put some in with a hand pump. But it still won't engage in drive and if it does it only creeps and then quits again. Reverse works fine. Do I need to reset something or does it sound like the tranny is bad? And if it is bad what tranny is in my car?