Hi, I have a 91 toyota pickup with a 3.4L swap and I want to do a transmission fluid change. Its an automatic, 230k miles on it. A few questions. Forgive me if I sound ignorant, I know my engine inside and out but my transmission knowledge is quite limited. I've seen this covered in some other forums but still am not getting the exact answers I need since a lot of them are older.

-I've heard flushes are bad news, is this true? I know that a empty and fill only changes out a few quarts, is there a way to change more out, and possibly get everything changed? I know there is typically some in the torque converter etc. anyway, in short, is there a way to swap it out without officially "flushing" it.

-In the manual I'm not seeing anything about driving it before the change. Would anyone suggest this and if so is it just your basic ten minutes of driving?

-When I change it I've heard of changing out some other things like the filter. I'm not finding any that are OEM. does anyone know a place I can find one that is? If not are there any other brands that hold up?

-Would anyone suggest me doing anything else since I plan on dropping the pan?

I plan on doing the method where I empty and measure how much I empty out and then fill that much, any objections to doing so?

Thanks all and sorry if this has been covered a million times. Mostly in the older ones it wasn't clear if they were actually talking about an official "flush" which I had heard negative things about vs empty and fill.

thanks!

 

I feel like flushes get a bad rap because people always do them when it's far too late and the transmission is on it's way out. I have done the home flush before with good success, you just route the suction side of your transmission cooler into a 5 gallon bucket of ATF and route the side into an empty 5 gallon bucket and start the engine and let it run until you either overfill the empty bucket or just about run out of clean ATF.

But to be completely honest there's not much of a need to that as long you do frequent ATF/filter changes because most of the junk you get in a transmission is going to fall to the bottom of the transmission
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Toyota does have a pretty heavy-duty strainer in the pan, but there’s no reason to replace it every time. Just clean and re-use. Unless the wire mesh got damaged somehow. That’s assuming the oem strainer is still there, of course

 

Lubegard Red is about the only trans fluid fortifying additive I'd recommend.