NOTE:
It is recommended (but not required) to do the Magnefine installation at a time of transmission fluid drain for best results.
It might be a good time to do the transmission cooler line flush at same time, since you will be unplugging the ATF cooler hoses.
However, draining transmission is not necessary, fluid spill from disconnected hoses and lines on both ends will be similar no matter if transmission is drained or not 
I just did both things at same time on my V6.
In past I installed Magnefine (with new hoses) on 5s-fe without draining anything. However I was doing transmission flush via a cooler line at that time, also I didn't even remove the fan assembly (nor battery) as there was just enough working space on 5s-fe (scratched and burned my hands though) to get it done with car on ground.
This DIY assumes, you will be draining the transmission (and differential on V6) at same time, if you are not willing to do so, just skip the drain related steps.
Just remember to check fluid level after Magnefine installation, as some fluid will get spilled, so it will need to be topped off at hot car.
On a V6 model it is a must to remove the driver side fan, and most likely it will require removal of battery first in order to do so, working space is tight.
On an i4/2.2L model it is recommended to remove driver side fan (still doable with fan installed, it's hard though) for easy access to transmission cooler pipes at bottom of radiator, besides that working space is open.
Pre-requisites:
-
10mm allen wrench / hex key with long arm and a cheater pipe (for differential drain plug on V6)
-optionally 17mm shallow 6-point socket on 3/8'' dr ratchet (and a cheater pipe) for differential fill plug on 2.2L i4 (can be done at other time)
-optionally (recommended)
10mm hex bit socket for 3/8'' drive (and ratchet or breaker bar) for transmission drain
-1/4'' & 10mm sockets on tiny 1/4'' dr ratchet
-3/8'' dr torque wrench, e.g.
like this
-1/4'' dr torque wrench, e.g.
like this
-pliers
-large scissors
-bucket which fits under frame of a raised front end
-3/8'' ID clear flexible vinyl hose (4-5ft should be enough) from Home Depot or so
-Magnefine filter off ebay like
this (4 pack)
-around 3ft (1m) of bulk NAPA 3/8'' transmission oil cooler hose, you may want a longer piece in case you screw up the 1st time trimming and end up having no more long enough pieces

-6 matching NAPA clamps for new hoses (worm gear type is best)
-lots of shop/paper towels

-at least 4qts (for trans+diff refill on 3.0L V6) or 3qts (just trans refill on 2.2L i4, if doing diff to at same time then have 2 more quarts handy) of new fresh ATF
-about 2 hours of time at slow pace and a few 5 minute breaks :thumbsup:
Before you start, it's recommended to use PB Blaster on both transmission and differential (V6) drain plugs (and a diff fill plug for 2.2L) if they haven't been touched in a while.
*BELOW PICS ARE TAKEN FROM 1MZ-FE (2002 Solara V6 / A541E)*
1. Warm the car up by driving 15-30 mins past reaching the engine operating temperature (most of dirt particles will easier drain out from trans and diff)
2. Park the car on level ground, set the e-brake and put wheel chocks behind the rear tires. Raise the front end high enough, so your waste bucket fits under the frame behind differential drain plug
3. Secure the car with jack stands under front sides of frame or use factory jack points behind mud guards.
4. Pull out the transmission ATF dip stick and put at side of engine bay on some paper towels. Drain the transmission by opening the 10mm hex bit drain plug (torque for re-installation is 36ft-lbs), place the bucket under drain plug before removing it completely
5. This is what you will be working on soon, as you can see clearance is tight, so we need working space.
6. While transmission is draining, unclip the small fuse box off the battery holder arm, then unbolt the battery hold down arm on both ends (10mm socket), disconnect both battery terminals and remove battery and the plastic tray under it off the car.
7. Disconnect 2 wire connectors on driver side fan shroud, upper one is for driver side fan motor and the one below it is for fan switch harness (wire is routed around the shroud and at its bottom).
Make sure NOT to use pliers on them!!! both connectors have a clearly marked place for pressing on the tab with your thumb while pulling the plug away (you can hold the socket with other hand to make it easier). Use some plastic safe cleaner (no residue), e.g. electronic parts cleaner/spray (e.g. QD electronic parts cleaner) on connector first if it is dirty. Dirty connectors are hard to disconnect.
8. Unbolt the driver side fan on top (2 bolts 10mm, torque for re-installation is 44in-lbs)
9. Unclip the harness of the side of fan shroud (2 clips) and slide the fan assembly out slowly, rotating it so you can eventually unclip the plastic clip holding it's connector to the shroud (use pliers on its sides).
10. Once there you have clear access to transmission oil cooler hoses.
11. If transmission got drained completely by now, flip the metal gasket on the drain bolt and re-install it in the pan's bottom (36ft-lbs).
12. Place bucket under the differential and use 10mm allen wrench (long) with a cheater pipe to open the diff drain (remember counter clock wise and mind your perspective!!!)
*SPECIAL anti-fubar step for 2.2L IF you want to drain differential too at same time (totally optional, it's a separate chamber on A140E)*
LOOSEN the 17mm (socket) differential fill plug BEFORE loosening the differential drain plug!
More information on draining and refilling 2.2L differential here:
http://www.toyotanation.com/forum/showthread.php?t=197974
13. Now, while differential is draining, loosen with pliers the clamps on both ends of both hoses. Best way on radiator side is to first twist them for easier access and then move away from ends.
Use a hand to twist either of hose ends to sides several times until you feel it breaks free. Place some paper towels under each connection and first unplug the hoses on transmission side (both).
14. Temporarily attach clear 3/8'' hoses to transmission cooler lines (pipes) and route them to bucket.
Then temporarily insert car battery and connect the terminals (only hand tight), start the car for 1-2 seconds and shut it down, remove the key from ignition.
15. Look at the clear hoses and note which one turned red and which one is clear (empty). The empty one marks the side (line) for trans oil return to transmission. This is the line where you want to install the Magnefine filter on (flow arrow pointing towards the transmission).
16. Disconnect the battery and remove from car to get working space again.
17. Disconnect the clear hoses from transmission, route (bend them) original ATF cooler hoses from radiator to the bucket and let them drain out. Once they are more or less empty then unplug the original ATF cooler hoses from radiator (some fluid will spill from ports).
18. Now you need to remember which hose is which, so don't mix them and don't swap the sides, you want to place them on ground as they are on car.
On my car the left hand side hose was the transmission outlet to radiator (hot fluid), I only trimmed the new one to exact same size (wanted to replace it anyways while at it).
On my car the right hand side hose was the trans oil cooler return (transmission inlet). Place you filter closer to top portion of hose leaving some space for the inlet pipe (around 2 inches will do) and estimate the lengths of remaining hose connections on both sides of filter and then cut them from new bulk hose.
19. Use some ATF on filter connections (easier to slide new hose on it this way) and temporarily install clamps. I found that using 1/4'' socket and 1/4'' dr ratchet is fastest for loosening and tightening those NAPA clamps, much better this way than using a screw driver possibly stripping the adjustment bolts eventually when making them tight.
This is what I got after a while of tinkering, filter was placed in top portion of hose (most optimal, you will see later in pics on car):
This is what I tried earlier. I wanted to place filter below the fan shroud, at bottom of return hose. But it didn't work out as the fan shroud was coming in contact with filter body even before reaching its mounting holes. THIS BELOW WON'T WORK!
20. If the differential drained by now, flip the metal gasket on the drain plug and install it securely back. Torque is same as pan drain bolt, but since no torque wrench fits on it, then you have to do it by feel (don't over tighten too much!!)
21. Install you new trans oil cooler hoses back on car, make sure the hose ends go all the way onto pipe connections just like original ones did and see how it looks like. MAKE SURE NO HOSE IS COLLAPSED OR TWISTED ANYWHERE!!!
Try inserting the fan shroud back in place and see if the clearance is not an issue for anything.
22. If all looks good then remove fan shroud and tighten all 6 clamps with 1/4'' socket and 1/4'' ratchet until clamps stop turning and maybe 1/4-1/2 turn farther to make them sit tight. BE MORE GENTLE ON FILTER PLASTIC CONNECTIONS.
This is how it looked like on my car when hoses were installed back in place.
23. Re-install everything in opposite order using proper torque for all bolts, don't snap anything please
24. Once all is in place, you will get something like this below. This pic shows the clearance between Magnefine filter and lower radiator hose (it's minimal, seems like less than 1mm, but things are not touching each other on cold car).
This is the same clearance picture on a warm car when coolant flows through the lower radiator hose, note how clearance is much bigger, around 7mm, no problem :thumbsup:
25. NOW LOWER THE CAR ON GROUND AND DON'T FORGET TO REFILL THE TRANSMISSION AND DIFFERENTIAL before starting engine and trying to drive

My car took 4qts even to refill both and compensating for Magnefine filter.
BTW, This time I used Mobil1 Dex/Merc Full Synthetic ATF from Advance Auto, I paid around $5.65 per quart when ordering online with a can of electric parts cleaner (code A123) and choosing local pickup after 1hr :thumbsup:
26. Check everything for leaks and make sure there isn't one after starting engine.
27. warm up the car (I drive it gently locally for 15 minutes) and check the level, you may want to fill it initially with 3-3.5qts of ATF first then shift through all gears (one by one), drive a bit, check level on running car after 15-30 minutes. refill as needed.
I usually leave the car for 2-3 hours and come back to it later, this time allows the fluid to drain down to pan completely. Then I make it hot driving locally and refill as needed on hot running car up to lower HOT mark.
then I drive it again (highway this time) and check the level again and make sure it touches the upper HOT mark once everything is HOT.
If all worked out nicely like it did for me, then have a cold one and enjoy having a clean transmission :clap:
*BELOW REFERENCE PICTURES WERE TAKEN FROM 5S-FE (2000 Solara 2.2L / A140E)*
This is how the transmission oil cooler lines look like on 2.2L model, note how they are crossed over (1mz-fe/A541E are straight through):
However on my wife's 2000 Solara 2.2L also the same line was a return (but since pipes were crossed over then technically it was opposite).
This is how installed Magnefine looks like on 2.2L model with A140E transmission.
Procedure is same for 5s-fe as for 1mz-fe, but you will NOT have to remove the battery off the car.
I actually did it while the driver side radiator fan was still installed on radiator and without draining the transmission ... just cut my both forearms a bit and burned my left forearm by touching hot exhaust manifold heat shield (now have a scar for lifetime LOL :lol

due to clearance issues with things in place, but to make things easier just remove the fan assembly (same thing as V6) and it will be real easy :thumbsup:
Automatic Transmission Fluid drain and refill capacity per Owner's Manual:
a) 1mz-fe / A541E
transmission AND differential up to 5 quarts (4.75L)
b) 5s-fe / A140E
transmission up to 2.6 quarts (2.5L)
differential 1.7 quarts (1.6L)
Disclaimer:
If you screw up something or hurt yourself…that’s your fault. Neither myself nor TN are responsible for any injury, damage, or even death caused by this DIY