How can you drain my transmission completely on a Volvo s90 1997 when you drain the pan you get 3 quarts out and the manual says it takes 7.4 quarts where is the rest and how can you drain it?

Answer 1

You can flush the ATF yourself by locating the two oil-cooling-lines connected to the radiator.

Connect clear 1/2" inner diameter clear plastic tubing from Homedepot to the output line, and put the other end into a clear milk jug. TURN ON THE ENGINE and ATF Fluid will rush out of the cooling line.

After 2 quarts have come out the system, take out the ATF dipstick and fill 2 quarts of fresh new ATF. Repeat the process until oil in the output line appears clear/cherry red. This process may take 12-20 quarts of new ATF fluid. When you're done, plug the output line back into the radiator and check the fluid level from the dip stick.

If you over filled, you know how to take some out of the system by starting the process again.

{The rest is in the torque converter, the cooling lines and tank. The only way to completely change the fluid is to use a transmission flush machine which does its work by connecting to the transmission cooling lines and let the car run at idle. This is not the type of job for a do it yourself person. I have been a Volvo master technician for more than 30 years so please allow the dealer or a qualified repair shop to perform this job. The transmission in the 960/s90 and engine are almost bulletproof if properly maintained. Seeing one with over 300,000 mile is not unusual.} You will know quickly if you have the hose on the wrong line. Transmission Fluid will go EVERYWHERE. Note: The trans lines are 960/S90 are notorious for stripping the threads. Also be sure to turn the engine off when you have 2 quarts in the jug