Unknown Plugs on Transmission

Hello everyone,

I'm looking for a suitable drain and pressure source for my add-on transmission oil filter. When looking at some pictures off of ebay of used transmissions, I came across a couple of plugs that aren't discussed here or in my manuals. One of these is listed on
OEM Toyota Parts Online | Village Toyota Parts
as a "Plug for Front Differential Filler". Was wondering if anyone can recognize the plugs marked with green in the attached picture. Would you also know if any is a pressure source or drain for the Transmission oil or Inverter coolant? Thanks for your time.

 

Another reason I'm asking is I have the volume 1 service manual and these plugs aren't mentioned. Does TIS have this info?

 

Yeah If I can find a location to mount a bypass filter it'll happen. I may get a tiny flow rate out of the pump but it shouldn't matter.

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My only concern is that the filter will divert too much flow from the trans so Ill be monitoring the before and after temperatures of MG1 and MG2. I can always get a smaller restriction orifice. The spec for the trans pump is only 0.4 PSI so I may have to find a small external pump.

It'll add about an extra quart to the sump and provide more cooling.

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The filter is similar to: Frantz Filters, LLC. Official Website

Bob (Bwilson4web) had the transmission oil changed and analyzed three times. His results were that the oil oxidized, got thicker, and it's good to change it every 30k to keep the viscosity and wear down. I'm hoping to install a bypass filter and then change the element every 10k. The goals are to never need to drain the transmission fluid and to substantially reduce wear.

I bought Bob's Prius last month and hope to continue the tradition of keeping the transmission clean. Several years ago I put a Frantz on a '95 Saturn transmission and it became like a brand new transmission shifting perfectly all the time. Of course, the Prius doesn't have gears but I still believe in the benefits of clean ATF.

 

If the plug above the fill plug (bottom right of my pic) is also attached to the transmission sump it will be easier to use.

 

I understand. The filter would come off when I sell the car.

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After reading this SAE article about the P410 I have a better understanding of how the transmission pump is used. The article states that 50-70% of the heat from the gears and motors is dissipated by dripping ATF onto the transmission. Unless the oil pump has a relief valve (like the engine's oil pump) - it's a very bad idea to bleed pressure from this pump.

There's another way to pump oil to a bypass filter. A low pressure, low power, 3-12V DC fuel pump can be bought online for <$10.

I would still need a place to pick up the ATF. Installing an adapter into the bottom of the transmission in place of the drain plug doesn't appeal to me. If that fitting ever leaked it could drain the transmission and I'd be SOL. It's safer tapping somewhere else. If the "Plug for front differential filler", facing the hood, gives access to the reservoir I might be able to run a metal tube into the reservoir that feeds a pump.