1995 Trooper, 120K miles, Engine loses power when driving uphill (drops from 70mph to 55mph).

What do you think is the culprit?


I don't think that this Trooper has had anything major replaced before. My friend is poor, I'm trying to help him figure out whether he should keep this car or trade it for another one. He needs a vehicle with more mass than a car because he is very protective of his family, and has anxiety about their being involved in a crash.