There are two lines on the passenger's side of the transmission up front near
the converter; the lower one is the "To Cooler" line and the upper one is the
"From Cooler" line. If you disconnect the "From Cooler" line from the transmission
you can put it in a bucket and flush to your heart's content.

In case you haven't seen the Jiffy-Tite style connector before: Slide back the
plastic cover over the c-clip-shaped spring, then use a small screwdriver to
pop the spring out of its groove.
KEEP A FINGER ON THE SPRING AS YOU DO THIS,
because those springs just love to go flying off into some dark hole where
you'll never find it. Once the spring is out,just pull and wiggle on the line
until it comes out of the fitting. As soon as you have the line out you can put
the spring back into its groove so you don't lose it - the line will snap right
back into place when you're done, even with the spring there.
Be careful not to damage the o-rings when re-installing.

A few other tips for your pan swap...
When you're removing the old suction filter: if the seal stays in the bore, don't use a screwdriver
 to pry it out. Just wipe off the neck of the filter, wipe out the seal, and reinstall the filter.
 Cock it sideways a bit and pull down again - the seal should come out with it.>

Your refill quantity will be 10.5 quarts or roughly 2.5 gallons. This
is with the deep pan, and does not include the cooler lines. The torque
converter holds roughly 4.5 quarts in addition to the 10.5 quarts. Obviously
this means you will have a mixture of TranSynd and Dexron. The two fluids
are compatible.

I bought a 5 gal pail of Transynd ($125) and poured two quarts in clean
containers just in case I needed to add any in the future. The remaining
4.5 gal went through the tranny - start the engine, run a few quarts out,
shut off the engine, add more Transynd and repeat until it was all in.
Lucked out that my final check was right on the correct fill level
(checked HOT as per the manuals).

If you refill with Transynd as I did, you will have about 58% Transynd.
After the second fluid change using Transynd, you will have about 80%
and over 90% at the third change. If you plan on switching to TranSynd I
recommend you buy 3 Gallons and pull the "From Cooler" line loose from
the transmission (install a short hose into a bucket) and start the truck
up to flush (the majority) the Dexron 2 out... I over fill the pan by 2-3
quarts when I'm doing this...

You "feed and bleed" , *DO NOT* pump your tranny dry!! You install
your filters, pans and whatnots, fill her up to the "cold" mark with new
fluid. Then hook up your flush hose and also feed new fluid down the
dipstick hole while you are pumping. After pumping about 2-1/2 to 3 gallons,
stop, reconnect the flush line, fill back up to the cold mark with new
fluid. Then start it up and work your way through all the gears
(holding the brakes), pausing for a few seconds in each selection.
Take her out for a spin around the block and drive for about 15-3O minutes.
Then come back and do the through-the-gears routine again before winding up
in Park and while still idling check for fluid at the "Hot" level. Adjust
as necessary and you are set!

No.. What I'm saying is after you have drained the fluid and replaced
the spin-on filter you can remove the "From Cooler" line and install
a short piece of hose into a bucket... From that point I hope you measured
about how much fluid you took out of the trans including the filter...
Now install the same amount +2-3 more quarts and start the truck up
(it may take a few seconds for the fluid to start coming out so don't
be alarmed if it does this) You should be able to tell when the Dexron III
 stops and the TranSynd starts. At that point cut the
truck off and reinstall the Cooler Line.. Now crank the truck back up
(check for leaks) and place it in Drive-Neutral-Reverse then back to PARK..
Do this a few times then check the Fluid level.. It should be on the "COLD FULL"
line if not add Fluid until.. Then as idle chatter said, drive it around
to get the trans temp up then check to see if it's at the HOT FULL mark
if not add fluid..

Pan bolt torque - 18-21 ft-lbs.
Drain plug torque - 25 ft-lbs.

Pan: 29536522 $48.87 PHOTO
Gasket: 29536526 $29.36 PHOTO   GASKET NOT REQUIRED UNLESS DAMAGED
Filter-Suction, Deep: 29537966 $21.22 PHOTO
Spin on filter: 29537268 $8.87 PHOTO

...Prices may vary.....