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It is the same as the Highlander gen 2, so this link will show what you need to know. With both, you just fill them until fluid comes out the fill hole and then you are done! Always loosen the fill bolt first! It is a huge problem to drain the fluid then find out you cannot get the fill bolt loose!
Also do some www.youtube.com searching for both RX350 and Highlander as I think there are some videos.
FYI here is a list of all the Highlander DIY tips as many apply to the RX as they are 90% the same mechanically (only the rear suspension is different)
i found this pump useful for filling my transmission and diffs...it has a nice clip so the hose doesnt fall out while pumping into the fill hole..only problem is that the pump doesnt fit directly into some brand bottles ..but if you have a gallon milk jug for the fluid it will work. Its easy enough to take it apart and retrofit a different size sealing cap that is drilled out. https://www.pepboys.com/product/deta...052?quantity=1
I was attempting to remove the fill plug on the rear differential and the allen head was really rusted and in bad shape. I hammered in the 10mm hex head and got a pretty good grip but as soon as I tried to break it lose, it started to strip. Now the bolt is loose and I might have to use a bolt extractor to remove it.
Anyhow, anybody got the part # for the fill and drain bolt on the rear differential ?
Google Lexus South Atlanta Parts they have a great website with exploded drawings of all the parts. It will be there. Or hunt on eBay for 2008 - 2012 Highlander differential fill plug. They are twins and that is a part that will rarely change.
I just changed my Xfer case and rear Differential oil at 47,000 Km (29000 miles) and had the oil analyzed. The Xfer case results were fine but the rear diff was contaminated with dirt and had abnormal wear indications. I need to check the breather and dust seals to make sure they are OK. Seems strange to see so much dirt in there. Will definitely change more often to watch what is happening.
I took our 2015 in for the 30K mile service at a Lexus dealer in Denver. The service writer recommended changing the gear oil in both diffs if we did a lot of mountain driving. We don't, so I said no. He then said it will NEED to be changed at 60K mile service. Yeah, sure, if we still own the RX.
I just changed my transfer case and rear differential gear oil on my 2010 RX350 at 122,000 Km, used Mobil 1 synthetic as it is less expensive that the Toyota fluid. I raised the vehicle and made sure it was level. The rear diff was relatively easy after spraying penetrating fluid and using a wire brush to clean the area. Being in Ontario Canada the underside is fairly rusty. I used a 10mm hex male socket with a breaker bar handle. The drained fluid front and rear looked pretty dirty and smelled like rotten eggs, pretty nasty stuff. The front transfer case was a bit more challenging, of course removing the fill plug first. Access tight near the exhaust pipe. I found I had direct line of sight by using two 12" extension bars joined together and essentially untorqued the plug with direct access with a 24mm hex socket . The drain plug was also a 24mm socket and that one was easy access from directly below. I wish I had bought new crush washers ahead of time, as I cleaned and reused the original ones but clearly they were slightly deformed. Both magnetic drain plugs had considerable metal particles attached. Here are few pictures. Rear diff with plugs already removed transfer case drain plug transfer case fill plug view from two feet back, direct access with 24" extension locations.
I just changed my transfer case and rear differential gear oil on my 2010 RX350 at 122,000 Km, used Mobil 1 synthetic as it is less expensive that the Toyota fluid. I raised the vehicle and made sure it was level. The rear diff was relatively easy after spraying penetrating fluid and using a wire brush to clean the area. Being in Ontario Canada the underside is fairly rusty. I used a 10mm hex male socket with a breaker bar handle. The drained fluid front and rear looked pretty dirty and smelled like rotten eggs, pretty nasty stuff. The front transfer case was a bit more challenging, of course removing the fill plug first. Access tight near the exhaust pipe. I found I had direct line of sight by using two 12" extension bars joined together and essentially untorqued the plug with direct access with a 24mm hex socket . The drain plug was also a 24mm socket and that one was easy access from directly below. I wish I had bought new crush washers ahead of time, as I cleaned and reused the original ones but clearly they were slightly deformed. Both magnetic drain plugs had considerable metal particles attached. Here are few pictures. Rear diff with plugs already removed transfer case drain plug transfer case fill plug view from two feet back, direct access with 24" extension locations.
Nice job there. I did mine at 82K miles. And all fluids were clear without metal particles. But that diff fluid smells very bad.
[color=#222222] I used a 10mm hex male socket with a breaker bar handle. Access tight near the exhaust pipe. I found I had direct line of sight by using two 12" extension bars joined together and essentially untorqued the plug with direct access with a 24mm hex socket . The drain plug was also a 24mm socket and that one was easy access from directly below. I wish I had bought new crush washers ahead of time, as I cleaned and reused the original ones but clearly they were slightly deformed. Both magnetic drain plugs had considerable metal particles attached. Here are few pictures.
Thanks for this info. I now know to get a 24" extension before I start this job
I assume the differential gear oil is another fluid that Lexus considers to be "lifetime". We all know there is no such animal.
So at what mileage are you folks changing your differential gear oil? And what type and weight of aftermarket gear oil are you using?
I have an 06 Highlander Limited that I got with 109,000 (now has 167,000) and picked up my 13 RX350 with 85,000 in May. Both are AWD. I changed all fluids and went with full synthetics when I purchased them. On the Highlander, I've been changing out the fluid every 20-25K. As would be expected, the front is usually more dirty than the rear. In fact, I could lengthen the rear differential interval and be fine.
I looked up the history on the RX and didn't see that it had ever been changed although I suspect at some point it had because the gear oil wasn't dirty.
Thanks for this info. I now know to get a 24" extension before I start this job
I just checked the tool length, sorry I made a mistake, I used two 8* extensions and not two 12" extensions. I suspect you would probably be good with anything longer than about 10" total. You might be able to fit a 3/8" drive socket wrench with a really shallow 24mm socket but I only had a deep socket in the 24mm size. I plan to change both fluid locations (diff and transfer case about every 50 000 km as I do some towing maybe only 5% of the time. I too used Mobile 1 75W-90 full synthetic. This is definitely the first time the fluids were changed at 120 000km and I found the rear diff to be worse (darker oil) and the plug had more debris on the magnet.
05-15-18, 07:43 AM
