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W-Body Performance - Pushrod / DOHC
TTs - Transmission Fluid (Automatic)

"I'm giving it gas, but nothing's happening..."

Another maintenance item is the transmission fluid.  One of the major ways that the tranny fails to work is from bad / burnt fluid.  This project is quite is easy, and recommended if a buddy help you out as well.  The process is know as a torque flush, since the car's torque converter in the transmission basically does all the work for you.  Please read all directions before preforming procedure.
1.) First place front end of car on wheel ramps or properly lifted to slide underneath, shut off car
2.) Find the transmission cooler line on the bottom of the tranny that the connection vertically points up and down
3.) Loosen and remove fitting of transmission cooler line
** after fitting is removed there will be some fluid that will drain out of the line and the unit.  Be ready with a giant drain bucket / rags **
4.) Start car and begin pouring in the new tranny fluid into the dipstick tube while the torque converter is pumping out the old fluid below
5.) Flush about 30 pints through the tranny, or untill exiting fluid is a red / deep pink
6.) Run car till all fluid is pumped out and air is begining to spit out of the unit; shut off motor
** letting the engine run with no transmission fluid is not healthy for the torque converter; once you see air being pushed out, shut down car imediately **
7.) Re-install the transmission cooler line and tighten snuggly
8.) Check owner's manual to see what capacity the transmission holds; remember there is some extra fluid still in the tranny, so pour in a couple less then what's recommend
9.) After filling tranny, start car and switch gears about every ten seconds or so (e.g. R, D, 3, 2...).  Run that sequence at least twice; then place car in Park and check level.  If level is low add accordingly, and re-run gear sequence
10.) When level is correct, clean all excess fluid and mess.  Drive car normally checking for any leaks the first week; re-check fluid after end of week since air bubbles can affect fluid level


Underneath, when facing towards the driver side of the car, you'll find this: the front of the transmission pan and the two tranny cooler lines.  The horizontal line (full of grime and dirt) is the return line from the tranny cooler located, in front of the radiator; cooled fluid flows into the transmission there. 
The vertical tranny line, just right of the return line, is the "out" line, pushing scorching hot fluid to the tranny cooler to prolong fluid life.  Picture from a 1995 Pontiac Grand Prix GTP, all other W-Body models will apply.

- Average Time:  45+ minutes with help of a friend
- Scheduled Maintenance:  every 15K miles or when fluid color is tan / brown
- Written by Erik Melander