Automatic Transmission plug drain and filler plugs ... replace?

[westslope]

Thinking I should drain and refill the Automatic Transmission. Done in January 2020 and we are now 4 years later. Towed once since then.

Question: Should I replace the drain and filler plugs as well as the gaskets or can I, similar to the rear differential get away with re-using the existing plugs and gaskets installed in January 2020?

 

[IM1RU]

No need to replace the plug, and the crush washer is the same one as the oil pan plug. They are cheap. That said, you should really do the poor man's flush and get a complete fluid change. Your transmission will thank you. I do it every couple years.

 

[westslope]

Thanks @IM1RU. I performed a poor man's flush back in May 2020 about 41K km or 25K miles ago. Thought I could get away with a drain and refill this time around.

 

[westslope]

Question and a solicitation for opinions from everybody:

Disregarding expense and effort, it is always better to perform a poor man's flush of the automatic transmission than a drain and refill?

 

[Muadeeb]

Pmf will be better as you're getting fluid out of the torque converter and valved off portions of the body. Drain and fill will just get the pan and whatever you let drip out.

 

[IM1RU]

it is always better to perform a poor man's flush

yes