DIY transmission “poor man’s” ATF flush - writeup? (3 Viewers)

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Super77

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I have 12 fresh quarts of Toyota T-IV waiting to go in, but I can’t seem to find a definitive how-to with good pics/video of how to perform a DIY flush on an early 100 (with trans dipstick). Feels like this should be in the FAQ?

I’ve found some wandering threads on the topic, and some videos on the later (dipstick-less) models but those are different transmissions with extra steps for measuring fill. I’m looking for a vetted, no-nonsense step-by-step that applies to a 99. I did a “Rodney flush” on my 62 so familiar with the basic idea of swapping out 90+% of the fluid, not just diluting the new stuff in.

Point me the right way?
 
If you have a 99 with dipstick, Toyota IV is the WRONG fluid (I made this same mistake). Our 4 speed takes DEX 3. Guys at toyota and lexus dealership did not know and just gave me IV. Finally one guy who actually knew something said there should be a marking on the dipstick with fluid type. Sure enough, it was Dex 3. Also, my transmission drain bolt is original and it had DIII stamped into it. I ended up putting in valvoline transmission fluid (red bottles/Dex 3 compatible).

Tip: I did the transmission fluid transfer on my 2000 lx470 (dip stick). I first bought a clear home depot bucket and poured in water, 1 quart at a time and made graduated marking on the outside. This allowed me to turn engine on, trans pump did the work of putting in bucket and I would turn off engine after 2/3 quarts, add the corresponding amount into fill hole and repeat until I went through about 14 qts
 
If you have a 99 with dipstick, Toyota IV is the WRONG fluid (I made this same mistake). Our 4 speed takes DEX 3.
There's confusion around this. I can't find a thread here that concretely resolves it.

My ‘99 manual says Dex3


IMG_8633.webp

So do the 2000, 2001 MYs, according to the manuals you can view on TIS.

Starting in the 2002 MY, you see this:
02LC100-UM.webp


So, around 2002 Toyota seems to have changed the ATF spec for the A343F. If that is the same transmission in the 02, 01, 00, and 99 MYs, then logically you can reverse-apply that to a 99. Obviously they could not update the printed manuals, and Toyota never seems to have issued a TSB around this, and since T-IV is not dex3, it leads to confusion. However, I believe that many dealerships use T-IV in early gen LC100s.

I find hard to believe that Uncle T would tell them to go use Valvoline (even if it's dex3 compatible) when they can upsell customers to Toyota's 'official' ATF.
 
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If you have a 99 with dipstick, Toyota IV is the WRONG fluid (I made this same mistake). Our 4 speed takes DEX 3. Guys at toyota and lexus dealership did not know and just gave me IV. Finally one guy who actually knew something said there should be a marking on the dipstick with fluid type. Sure enough, it was Dex 3. Also, my transmission drain bolt is original and it had DIII stamped into it. I ended up putting in valvoline transmission fluid (red bottles/Dex 3 compatible).

Tip: I did the transmission fluid transfer on my 2000 lx470 (dip stick). I first bought a clear home depot bucket and poured in water, 1 quart at a time and made graduated marking on the outside. This allowed me to turn engine on, trans pump did the work of putting in bucket and I would turn off engine after 2/3 quarts, add the corresponding amount into fill hole and repeat until I went through about 14 qts
I bought a Cambro clear pitcher with the markings already for this. I used it on my wife’s RDX trans service I did. I drain 3 quarts, and replaced 3 until I got thru all 12 quarts.

I need to do this on my 2000 LX. I just want to know what exact hose I can pull to drain the old out, and refill from my dipstick.
 
There's confusion around this. I can't find a thread here that concretely resolves it.

My ‘99 manual says Dex3


View attachment 3955997
So do the 2000, 2001 MYs, according to the manuals you can view on TIS.

Starting in the 2002 MY, you see this:
View attachment 3956207

So, around 2002 Toyota seems to have changed the ATF spec for the A343F. If that is the same transmission in the 02, 01, 00, and 99 MYs, then logically you can reverse-apply that to a 99. Obviously they could not update the printed manuals, and Toyota never seems to have issued a TSB around this, and since T-IV is not dex3, it leads to confusion. However, I believe that many dealerships use T-IV in early gen LC100s.

I find hard to believe that Uncle T would tell them to go use Valvoline (even if it's dex3 compatible) when they can upsell customers to Toyota's 'official' ATF.
Simply put, according to Castrol, if you've got a 4-speed auto it's DEX-III and if you've got 5-speed auto it's WS (DEX-VI)
 
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I just did mine a few weeks ago. It was really straight forward and I normally screw up small tasks. If you pop the hood and look down between bumper and radiator/condenser, you will see two black trans fluid hoses. I disconnected the return line that is making its way back to the trans. Used a connector to attach a clear tube from that line into bucket with quart marks on the side (HD/lowes paint department sells these).

Steps:
1. Have helper start vehicle and let 2qts drain out into bucket. Then turn off vehicle.
2. Pour 2 qts new fluid in via dipstick tube.
3. Dump bucket into container for disposal so it’s empty and ready for another cycle.
4. Keep cycling vehicle on/off adding and removing fluid until it’s bright red or your out of replacement fluid.
 

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