louieolmos

Bought a 2010 RX 350 AWD last month with 120k miles from carmax. All I know is that the oil is fresh. No idea on brand/type, etc. No idea on the trans fluid nor diff oils… Finally had a free moment to drain and fill the diffs today… fluid looked mostly new but no idea on brand/type. Put in mobil1 75/90 and have logged it in my maintenance log. Next up is a trans filter change and fill with either amsoil or Valvoline ML.

this forum has been a great resource!

Felix

A few yrs ago I drained & filled the diff & tranfer case w/ Royal Purple 75/90 diff fluid....the transfer case was a little work to get at the fill plug thou. Great time to also do the trans as well.....

JW4RX350

4Gen RX350 AWD....I went to my Lexus dealer for rear differential & transfer case fluid change at 36,000 miles. I though the dealership would use Toyota oil but later found out they used BG system and fluid without disclosing it ahead of time...Anyway, at this point I want to know if it'll do harm to the transfer case.

Transfer case
BG 79264 Synchro Shift II GL-4 75W-80
Lexus manual calls for GL-5 75W-85
GL-4 is good for manual transmission. Can it be used in the RX AWD transfer case without issues? Also the viscosity 80 is lower than specified 85...possible wear?

Rear differential
BG 75364 Ultra Guard GL-5 75W-140
Lexus manual GL-5 75W-85
I know this is not a problem, might hurt the mileage that's all.

RealWing

GL4 and 5 are 2 different lubricants with different properties and additives. They put the wrong one in your TC.
Jim

Pinballer

Google difference between GL4 and GL5. GL5 is better for extreme pressure. In my humble opinion they put an inferior gear oil in your transfer case.

carguy75

Sound odd that a Lexus dealership would use two non-OEM products that are not even the correct spec of oil to use in your Lexus. I am not buying that a dealership performed your service.

Can you post a picture of the service receipt from that dealership that performed the work with the listed gear oils please.

JW4RX350

I contacted BG and they confirmed with my VIN # that my RX350 AWD TC and the rear diffs both take GL-5. (GL-4 and GL-5 are 2 different types of oils, I did quite a lot of reading after this)
The dealership flushed and installed GL-5 in my TC at no cost. As usual, they filmed part of the service process and sent me a link while I was in the waiting room.
Next time, check your service writeup...don't assume Lexus dealerships use Lexus/Toyota OEM oils.

RX in NC

A Lexus dealership doing a differential service at no cost to the customer? I would report that to the Guiness Book of World Records....

JW4RX350

Correcting a mistake is very different than doing a service, isn't it?

Clutchless

Yes, it is very different. It is a corrective service.
They are protecting themselves from future liability in the event a component fails due to use of improper lubricants that they negligently installed previously.