Depends on how much money your willing to spend. Idealy synthetic is the best however its expensive. Personally I use Castrol GTX high mileage. Remember since you should be changing the oil every 3K miles, its good to pick an oil that fits your budget
Need instructions on how to replace a manual window regulator on drivers side on 1995 saturn
Yes
R-134A
The thermostat on a 1995 Saturn SL1 is located on top of the motor. The largest hose coming off the radiator will have to be loosened to access the thermostat housing on the motor.
Buy a car that isn't a Saturn
My son's 1999 Salvaged/total Saturn SL1 was rebuilt using many engine and body parts from 1995-1999 Saturn SL1 and SL2 cars, I believe it will work fine. I do not recommend before 1995 or 2000 or later models. I do not recommend SL2 either. I am not the expert but most of my son's engine is not 1999 SL1. Good luck!
12.8 Us gallons
On the 1995 Saturn SL1 The oil pressure sending unit is the sensor closest to the alternator. The unit is on the back of the block.
It could be as simple as a few bolts need to be tightened, or it could be a worn/failed seal.
on the firewall side of the engine below the intake.
Thermostat bad or missing or engine not running.
In the alternator Needs new Alternator if it's bad