I have a 2017 LS460 (non-FSport) with 85,000 miles on the clock, and took my car into a Lexus dealer today to get an alignment. It's a long story about how I ended up at a dealership, but the short version is Les Schwab said all my control arms and bushings were shot when I took it to them for their free tire rotation. They said I needed an alignment, but it couldn't be done because all my control arms and bushings had "substantial damage." I got paranoid and took it to my Lexus dealer for an alignment, turns out the control arms and bushings were perfectly fine.
I'm a stickler for maintenance, and get everything done on time at a trusted independent mechanic, so I was shocked to hear the dealer tell me that I am waaaaay overdue for getting my rear differential fluid changed, as well as the transmission fluid changed.
I was shocked because the Lexus Maintenance Schedule only recommends the F-Sport version get it's differential fluid changed, and doesn't ever say change the transmission fluid.
Did I misread the maintenance schedule, or is this service not needed? I was certain it was not needed, but need a sanity check here. If it's needed, I'll get my independent guy to do it. Thanks in advance.

 

It is usually fine, I have serviced quite a few and it practically amounted to perfectly clean fluid being drained at miles ranging from 60k-220k miles for the rear diff. FRONT diff however does get a little more stressed out as does the transfer case.

 

There's no magic fluid that lasts forever just because it says " whatever OEM" on the bottle. When exposed to thermal cycling, humidity and mechanical action all fluids are breaking down and losing their properties. Yes, modern transmissions and diffs will last longer than 50 years ago but they still require maintenance, even if marketing folks saying otherwise. If you want your car to last beyond factory warranty you want ALL the fluids to be changed at least every 5 years or so. I have 2017 LS460 RWD with 50K on it and I did all that at 30K miles few years ago.
As for your rear diff fluid change. Well, maintenance schedule says you have to " INSPECT AND ADJUST ALL FLUID LEVELS" at 66 months or 55K miles, at which point you might as well drain it and refill it. Preventative maintenance is the cheapest kind of maintenance there is.

 

Thank you for this perspective. I think I'll get it done at my 90k mile service at my local independent. I think I was just taken back by the dealer, who wanted $725 to drain and fill the diff. and transmission fluids. They also made it seem like I'd been ruining my car. My reaction was probably a bit of shock and pride. Cheers again.

 

I have a 2013 LS460 that I bought with 86K on it. Since there was no record of the transfer case, front/rear diff change or transmission fluid change, I got all of them done since I want to get 300K out of my car. A good resource for those who want to get the most of their Lexus is the Car Care Nut on Youtube -- here is a vid on the transmission change question -- -- Here is one on the transfer case and diffs

 

Another question - is the transmission drain and fill, and the rear differential drain, simple enough to have an independent mechanic do it? Or is it safer at the dealer because they have the tech stream equipment, etc? The $725 the dealer quoted me seems high, but I'll do it if I need to have the dealer do it.

 

Any properly equipped mechanic should be able to take care of it. I prefer to use dealer for all scheduled maintenance just because of the maintenance records keeping for when I decide to sell my car, but otherwise local mechanic is just as good. This is not a space ship, it is pretty much just another Toyota. I've used my local shop couple of times for something similar on my 2017 LS460 and 2016 ES350. No issues whatsoever.