I got a 98 saturn sc2 with 201k miles. I believe the transmission is going out because one time when I floored it, it down shift but I wouldn't sift back up. I'm thinking of just putting in Lucas automatic fluid. But my dad says that I should also change the fluid in the transmission. I don't believe it has been changed for at least 5k miles, possibly more.Should I do a complete service of the transmission or just add Lucas?
Transmission fluid is usually changed around 40K-60K mile intervals, along with the filter if so equipped. Any idea when it was last done? What is the condition of your fluid? If fresh it will be bright red. If old it will be dark red. If really bad it will be burnt and gritty.
My dad said the last time was around 20k miles.
OK, it's still pretty fresh then. Changing the fluid is unlikely to do anything but if you're going to try Lucas you need to drain some out anyway so you may as well do a drain and fill. Assuming that's an electronically-controlled transmission it would be best to have it scanned for codes using a professional-grade scan tool. If lucky it might be something like a bad shift solenoid, though at that age and mileage it's likely the trans is just worn out.