Rear Differential & Transfer Case

[Lexmex]

Some of you may remember this photo.

My buddy Michael, whose RX-7 is on my car domain page, his wife had a Murano that busted its transfer case under 50,000 miles. Not a pretty sight after we took out the gear.

[thomas1]

There is one on the radiator and one on the engine block, just to the right of the oil filter when looking at the front of the engine....

[TunedRX300]

Originally Posted by thomas1

There is one on the radiator and one on the engine block, just to the right of the oil filter when looking at the front of the engine....

There are two on the engine block, see this helpful DIY thread started by Lexmex. I took a picture of where the 2nd engine block drain plug is, near the front sway bar.
http://www.clublexus.com/forums/rx-first-generation/249741-coolant-diy.html

[mrberl]

Guys, can somebody knowledgeable make it clear which types of fluids to use in:

Front Diff.
Rear Diff.
Transfer Case.

And which one is interchangeable with the ATF oil ?

Also, if regular gear oil is poured into the Front Diff (interchangeable with ATF?), will it mix with the ATF fluid ?

Thanks in advance,

Mrberl

[Lexmex]

Originally Posted by mrberl

Guys, can somebody knowledgeable make it clear which types of fluids to use in:

Front Diff.
Rear Diff.
Transfer Case.

And which one is interchangeable with the ATF oil ?

Also, if regular gear oil is poured into the Front Diff (interchangeable with ATF?), will it mix with the ATF fluid ?

Thanks in advance,

Mrberl

For transfer case and rear differential, a 75W90 gear fluid from any of the following, Amsoil, Mobil 1, Redline, Royal Purple would do just fine.

For front differential, which sits behind the tranny pan, only ATF, either Toyota Type IV or Amsoil ATF. Both the front differential and transmission are interconncted in terms of their fluid (even though they have separate drain plugs) and they are filled through the tranny dipstick (don't worry whatever you pour in will trickle on over to the front differential).

Don't pour gear fluid into the tranny dipstick. This is an error as we noted previously.

[mrberl]

Thanks for the reply, Lexmex.

Also, is there a way to check how much fluid there is in the transfer case and the rear differential ?

[Lexmex]

Originally Posted by mrberl

Thanks for the reply, Lexmex.

Also, is there a way to check how much fluid there is in the transfer case and the rear differential ?

Well, kind of.

First of all, technically there is .9 L of fluid in each. The bottle you normally buy to fill it up is .946 L total.

If you take off the fill cap of each and reach in with your finger you should be able to feel the fluid by slightly dipping your finger in there.

Best thing to do is that if you have not done this in a while or are not sure if you have done it in a while to go ahead and change the fluid.

The only time where you will lose fluid is in 2 cases:

1) you have a leak and can visibly see the fluid dripping out the bottom.

2) you have a leak, but it is the puddle is not visible underneath. This is because you have a leak on the top and the fluid will only exist under high pressure through the top of transfer case/differential. I actually have this with my transfer case, but it is a nuisance I live with since it is tough to get at the top of the transfer case (eventually I will).

Eventually leak number 2 stops as the fluid level/pressure combined is not enough to push the fluid up and out.

[ohiois350]

Originally Posted by Lexmex

For transfer case and rear differential, a 75W90 gear fluid from any of the following, Amsoil, Mobil 1, Redline, Royal Purple would do just fine.

For front differential, which sits behind the tranny pan, only ATF, either Toyota Type IV or Amsoil ATF. Both the front differential and transmission are interconncted in terms of their fluid (even though they have separate drain plugs) and they are filled through the tranny dipstick (don't worry whatever you pour in will trickle on over to the front differential).

Don't pour gear fluid into the tranny dipstick. This is an error as we noted previously.

For front differential, which sits behind the tranny pan, only ATF, either Toyota Type IV or Amsoil ATF. Both the front differential and transmission are interconncted in terms of their fluid (even though they have separate drain plugs) and they are filled through the tranny dipstick (don't worry whatever you pour in will trickle on over to the front differential).

Don't pour gear fluid into the tranny dipstick. This is an error as we noted previously.
_____________Hi Lemex, I have 98 camry v6, and I want to change the transmission fluid, beside the tranny pan drain plug, what else i have to drian? and is it the differential fluid and tranny fluid use the same fluid for front wheel drive? please help.

[Lexmex]

Originally Posted by ohiois350

For front differential, which sits behind the tranny pan, only ATF, either Toyota Type IV or Amsoil ATF. Both the front differential and transmission are interconncted in terms of their fluid (even though they have separate drain plugs) and they are filled through the tranny dipstick (don't worry whatever you pour in will trickle on over to the front differential).

Don't pour gear fluid into the tranny dipstick. This is an error as we noted previously.
_____________Hi Lemex, I have 98 camry v6, and I want to change the transmission fluid, beside the tranny pan drain plug, what else i have to drian? and is it the differential fluid and tranny fluid use the same fluid for front wheel drive? please help.

Right you are, I am happy you reinforced this. As mentioned only the AWD has a transfer case and a rear differential. But for everyone, both AWD and FWD, the transmission has two drain valves, one for the tranny on the pan, and one for the front differential, both of course take ATF only.

I know, because my uncle the first time we looked at it, was wondering if gear oil was supposed to go back there and that's how we actually found a separate, but inconspicuous fill hole on the back of the tranny above the front differential area.

With your Camry V6, you should have both plugs like on my RX300 as below. I believe it's the 4 cylinder version, the 2.2 Camry, that doesn't have this setup. The differential and the tranny use the same fluid. To explain this right so I don't confuse you, there are two drain plugs as you see below, but the transmission fluid for both areas is filled via the tranny dipstick at the top. The fluid trickles over to the front differential area (Takes up to 30 seconds from my experiment once in Mexico, where you can close up the tranny pan plug, leave the front differential plug open and watch fluid poured in the dipstick at the top come out the front differential plug, shown at left below).

Now, I did mention earlier that I found on the back of the transmission a separate fill hole. Don't concern yourself with this. It is our opinion that this was done for some factory reason in assembly. Just drain the two plugs and then fill up the tranny dipstick from the top.

[lexus114]

Lex,
For the front differential,you said it holds about .5 liters.About how much of a quart is that?

[Lexmex]

.52 or so quarts.

Keep in mind front differential is different from the transfer case.

.5 is about what comes out in terms of ATF out of the front differential if you have drain the tranny pan completely first.

[Lexmex]

Ah yes, almost that time of the year again for me, but decided to do my so-called annual changeout of the transfer case and rear differential.

First, let's recap the chain of events over the past year. Last April we changed out both the rear differential and transfer case to another round of Royal Purple. Over the past year I have had to add some BMW 75W140 to the transfer case due to a leak, the leak has been stopped not just due to that but also due to replacement of both seals. So we have had a mix in the front so to speak. The rear differential has remained the same.

Right now I have just about 128K miles, or 8K more than last year when I changed it out.

I have no Royal Purple 75W90 left, so this made for some interesting decisions, do I go for the .500 ml $30 USD 75W140 from BMW, the GM 75W90 1 liter also for $30 USD or something else. I was planning on stopping by Subaru to get some of their gear oil, but the only way they would sell it to me is in a huge drum.

Well by fortunate chance, right near my uncle's place on the highway is a little place called KM20 and they sold out of a drum, Pennzoil Synthetic 75W90 gear oil, http://www.pennzoil.com/products/gea..._gear7590.html

Now the particular bottle below is one they used to bottle it, but at just under $14 USD a liter, this was a nice bargain, and it is a good quality gear oil. I actually saw the drum they had there and I have known this group for all of my six years in Mexico.

For the tools one can use a 3/8th inch or 10 mm hex wrench for the rear differential and a 15/16th or 24mm bolt/wrench for the transfer case in the front. I used inch wrenches in this one, but metric will work, too.

All right now, let's get to the pretty pictures.

[Lexmex]

We flipped a coin and the rear differential went first. We put my RX up on the lift we had at the shop and proceeded to loosen the drain plug with a 3/8ths hex wrench extension

[Lexmex]

Another shot

[Lexmex]

Let her drain.