I'll be doing mine at 30K here... within the next two months.
A real rough procedure:
You'll want a large container to catch the fluid, and plenty of cardboard or plastic to throw down around the container if you want to save the surface your working on. ?It's a very very messy job.
I don't know exactly how much new fluid you'll need. ?I think between 4-6 quarts. I believe the manual states the exact amount.
There are a number of bolts all around the transmissions oil pan. ?I think there are about 12-16 or so. I heard the best procedure is to remove all of the 'center' bolts, and leave the four corners rather tight. ?You can go ahead and do that. ?
The bolts between the corners are probably seeping by now, and you're already making a mess. ?You'll want to start to back out one of those corner bolts. ?This is where all hell breaks loose. ?The fluid will start to flow, and go wherever it chooses. ?You will start to back out the other corner bolts a bit at a time, so that nothing is left torqued down too hard all by itself. ?It's best to do it so that one of the corners of the pan is just a little lower than the rest, so the fluid will hopefully spill in that direction.
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Pull the bracket for the shift linkage up and out of the way. I believe this is held on with those center bolts. ?In some cases you might have to disconnect it, but I don't think you will with the 4L60E's. ?I pull mine up and out with some wire or wire ties. It just makes this stressfull job easier.
When the fluid has stopped dumping, you can support the pan with one hand, and remove the bolts completely. ?Keep the catch-pan nearby, because there is still a ton of fluid in the pan... get ready for the weight when you pull out those last few bolts.
When they're free, tilt the pan a bit to try and drain out as much fluid in the pan as you can. ?When you've done that, you'll probably have to finagle the pan a bit to get it to clear crossmembers, exhausts, and shift linkages. ?You'll spill some more fluid doing this.
Once the pan is down and out of the way, you'll see the valve body sitting there slowly raining fluid around your catch-can. ?The filter is usually a 4x4 or 5x5-ish (in inches) sized flat piece of black plastic, hanging off the valve body. ?I believe you can see the filter element from underneat - it's usually white.
Pull down / unsnap the filter. It's just held in with friction. ?Depending on what filter kit you have, you'll also have to retrieve a plastic collar (with a metal ring around it) up inside the valve body in the cylinder you just pulled the filter out of. ?This is the biggest PITA of this job. ?It's hard to get at with conventional tools, and you don't want to gouge the cylinder that the sleeve is sitting in. ?Once you get it wiggled free, it comes out easily. ?My method to remove the collar was to drive through one side of it with a sharp screwdriver. ?this split it down one side, and allowed it to be coaxed out easier.
Once that's out - tap in the new one with a wooden dowel or something soft like that. ?It's easy.
In all honestly, if I come across this again, I will probably not go this extra step to remove/reinstall the collars. ?I didn't see any difference between them, and the new and old fiters fit the same either way.
Install the new filter in the same location as the other. ?Wiggle it around to make sure it's nice and snug.
Clean out the brownish sediment that adheres to the metal in the pan... make sure the sealing surfaces are clean. ? Now would be a great time to install a tranny-drain-plug kit... so that the next time you do this it won't be NEARLY as messy.
I used RTV sealer on my gastets, althought you really don't have to. I just ran a thin bead around both sides of the gasket, and stuck it to the pan. ?
I positioned the pan back up onto the tranny, and boltd it up. ?I don't have the torque specs handy, but they're quite light.
Fill the tranny with fluid... I think 4 quarts rings a bell with me...
Start the truck, and slide the shifter through all gear ranges. ?Let everything warm up and leave the truck in park.... Engine running. ?Fill the fluid as needed....
You're all set.
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There are other ways of doing this too, but this is a standard filter/oil change. ?There is still about twice as much fluid left in the torque converter... This is where a profesional flush would come into play, if you wanted to flush out all 10-12-to however many quarts are in the system.
I've heard of people disconnecting a tranny cooler line, and feeding fluid in the dipstick hole until clean stuff comes out of the cooler line, but I personally don't like that idea too much.
Hope this helps...
