Does Anyone Know What This Drain Plug Is For?

[lemon]

The drain plug circled in GREEN is the drain plug for the transmission fluid. The fill plug you can't see - it's above and toward the rear of the drain plug.

What I'm wondering is what the drain plug circled in RED is for? It's obviously part of the transmission as well. I don't want to remove it and have something important drain out that I don't know how to refill.

Both plugs are the same size and you need an allen key (or allen socket) to remove them.

[riwyle]

It is probably a drain for the fluid which lubricates the planetary gear set of the power split device. No maintenance required.

Why would you want to remove the plug?

[lemon]

It is probably a drain for the fluid which lubricates the planetary gear set of the power split device. No maintenance required.

Why would you want to remove the plug?

I don't. I'm changing the tranny fluid, and I know for sure that the green circled plug is tranny fluid. I was just wondering what the other plug was holding back.

[katzjamr]

you are aware the toyota world tranny fluid is full synthetic and rated to go 100,000 miles, are you replacing it with the toyota brand? and how many miles do you have at this time, i understand if you dont want to go the full 100K before change, just curious why you are doing it now.

[BadBrad]

I sure see a lot of rust under there. I reccomend moving to California. We are nearly as socialist as Canada, without the salty roads.

[lemon]

you are aware the toyota world tranny fluid is full synthetic and rated to go 100,000 miles, are you replacing it with the toyota brand? and how many miles do you have at this time, i understand if you dont want to go the full 100K before change, just curious why you are doing it now.

My maintenance manual says replace hybrid transaxle fluid every 72 months or 96000 KILOMETRES. Same for the rear differential fluid. My vehicle has 117000 km on it. I bought it used at 115000 km. Did the previous owner have it done? Who knows? For the minor amount the fluid costs (and the fact I can do it myself and save on labour) it's worth it to me. The rear diff I've already done.

By the way, the jury is still out on whether the WS fluid is full synthetic. Check at www.bobsitheoilguy.com

Also do a google on the fluid. It's not highly regarded by many people. Despite this, I am using it because I don't know what else is compatible with it. If I could find another fluid (Amsoil, Mobil whatever) that I knew 100% was compatible, I would use it.

[lemon]

I sure see a lot of rust under there. I reccomend moving to California. We are nearly as socialist as Canada, without the salty roads.

I bought the car used. Trust me, if I'd had it since day one, the underside would look different. I use Krown rustproofing (yearly oil spray) on all my cars with very good results (and Krown is recommended by the Automobile Protection Association). www.krown.ca Other cars I've had since new and Krown'd looked like new underneath after many salty winters.

Regardless, the RX is scheduled for a spraying next week.

[lemon]

Well, I've done some searching and I think the plug is holding back coolant. It's the coolant that circulates through the transaxle and the inverter.