My sister’s 2001 Neon is having tranny issues. I haven’t experianced it yet but she said that going down the highway it acts like the tranny pops into neutral and she floors it to keep the speed up. I already told her not to floor it but to pull over or she'll blow the motor. It will then pop back into gear. It’s done this a few times to her. Any idea what this might be and how to fix it? I haven't taken the pan off yet to look for any metal shavings. I'm hoping changing the oil and filter might help it, or at least extend it's life.

Thanks,
Dave