bored7one4

Hi,

I have a 99 Rx with 75k on it and now i would like to change my transmission oil myself. Is the any way i can get detailed instrustions on how to do so and how many of the toyota transmission oil quarts do i need?

also what type of motor oil does it take? 5w30 right?

TunedRX300

check out ederny's web and bookmark it. BTW putting engine oil into tranny is a big .
http://rx300how2.home.comcast.net/xm...id_change1.htm

phillyfan

This is a sticky and often discussed item. To start the following website has some information about this topic with pictures and how to do it. http://rx300how2.home.comcast.net/index.html

The problem comes that this procedure changes about 5 qts (only about 1/3 of the transmission fluid). The debate is what good is that without changing all of the fluid (including the differentials). I'm not terribly automotively versed but apparently this process is much more difficult. I know my local Lexus dealer quoted a $1000 price tag to do the job.

Search the forum here as there are several long threads about this topic. Some have had transmission failures right after changing their fluid (even by so-called professionals). My local mechanic somewhat voted against getting the fluid changed. To me it seems like something that should be done at some point. Again though, I am no expert, but if you read through some of the older posts you'll will have a sense of the various oppinions out there.

Fern

Draining and filling the lexus rx300 is preventative maintenance, just be aware that the trani has toyota trani fluid in it not "oil".

check your trani dipstick (pull it out and see what is written) it should tell you the fluid type, ie: Type IV, etc...

As far as the drain proceedures, check ederny's site and with reference to amount (if trani is shifting properly) conclude the correct fluid amount is in there now, therefore, just drain and fill from dipstick the same amount you took out.

BTW you do know that the trani drain plug is opposite the crankcase drainplug I hope.

Cheers,

ericok

Absolutely, positively use Toyota Type IV fluid ONLY. No other fluid is acceptable.

Yeah, a drain and fill changes less that half the total fluid but all automatic transmissions are like that. If you do it regularly, your fluid will be "relatively" fresh. If a shop uses a flush machine, all the fluid will be changed.

TunedRX300

AWD has 16 quarts, drain and fill 4.2 quarts replaces only 25%.

ericok

The official, genuine, factory supplied Lexus RX300 service manual says:

U140F Automatic Transaxle (the AWD unit) Dry Fill = 9.67 US Quarts Type IV. Drain and refill = 4.3 US Quarts.

The U140E (FWD unit) Dry Fill = 8.72 Quarts. Drain and Refill =3.7 US Quarts.

mikey00

When a transmission flush is done, they use 16 qts. This is because there is some waste of clean fluid in the flushing process. Many confuse this with the capacity of the trans.
A trick I learned on this forum is to not only open the trans pan drain plug, but also the front diff plug. This is also a 10mm hex about 6 inches directly behind the trans plug. The trans drain plug sits horizontally while the front diff is vertical. This gets about another quart drained, so now you are getting over 50% of the fluid. The front diff fills from the trans dipstick same as the trans.

Lexmex

Being in Mexico, I can only do drain and fill (all that Toyota would do down here anyway). My uncle and I plan to do this early in 2006 and do drain and fill 3 times (we can get the fluid at Toyota)...once each week over three weeks to get as much as possible out.

As far as motor oil, stick to 5W-30 for now at 75K. I use Mobil 1 0W-40, but keep in mind this RX owners races and 5W-50 proved too thick.

ericok

I've seen people post this trick to get another quart out of the front differential. But... the service manual says that the front dfferential holds 1 quart of 75W-90 transfer oil (not automatic transmission fluid). And it's filled separately from the transmission. I hope you're not draining your transfer case and thinking that by refilling the transmission you're replacing the fluid.

mikey00

The words "front differential" and "transfer case" seem to be used interchangeably by people on this forum. So call it what you like, there is another 10mm hex drain plug about 6 inches behind the trans drain plug that definitely drains ATF, about another quart, and fills from the trans dip stick.

TunedRX300

Definitely replace fluid with whatever is coming out of the drain plug.
Also I don't understand why there is so much confusion. No one EVER confuse about what is in the rear differential, it is GL-5 gear oil 80w90. It is logical that Toyota uses the same fluid for the front differential because differentials, no matter front or rear, perform the same function. Transfer case is part of the transmission and uses the same ATF since there is no separate fill hole. Tranny dip stick hole fills both transfer case and tranny.

kwhoughton

I know that this is an old thread, but probably is used for reference from time to time. "TunedRX300" Says since front differentials and rear differentials perorm the same function that they use the same fluid. that is true. However "Tuned" then states that since the transmission uses ATF and since the transfer case is part of the transmission, it also uses ATF. WRONG. Although the front and rear differentials do use the same fluid, that fluid is gear oil (not ATF) and is supplied from the transfer case to the front wheels or to all wheels in AWD. The Chasis spec. clearly shows that, calling for gear oil in the "transfer" and the same gear oil in the "differential" If someone is draining ATF out of the transfer case, it is probably because someone already made the same mistake before them.

Lexmex

I have to speak in TunedRX300's defense. I sometimes use interchangeably O2 sensors and A/F sensors, even though A/F sensors go before the main cat and the O2 sensor goes after, though on some vehicles there is no distinction.

And on some vehicles, transfer case and front differential can mean the same thing. I refer to the front differential as the area on the left that is near the tranny pan and does use the ATF. We discussed this in later threads about differences, but each person is correct. The transfer case to me is another area that only applies to the AWD version and uses a higher weight gear oil. Both TunedRX300 and I did some good threads with photos on this.

Lexmex

Transfer case is on the other side of the exhaust pipe and exists on AWD versions along with a rear differential. Both use gear oil. This is after I drained it.