Goodmorning. I'm new to this post but need advice as to how to best care for the GS350-Fsport. I have a 2013 and it has about 70,000 miles on it.
I am one who hates to take the vehicle to the local Lexus dealer. There is only one in my area and they are a rip-off artists in plain sight.
I have a reputable mechanic who works on performance vehicles and they tell me they inspect the vehicle each and everytime they do the oil-changes. All I get from them- is everything is fine. Maybe I should count my blessings.
The owners manuel says every 5,000 miles to change oil, inspect this, inspect that, A/c filter change, etc.....but never does it indicates and recommend to change transmission fluid, radiator fluid, etc....
I'm wanting to keep the care for a long time as I just love it- but want advice as to how to manage preventative maintenance???

David

-Do a brake flush
- Change your transmission pan filter and fluid

You may want to re-read your Owners Manual concerning engine oil and filter change. Also, concerning the transmission fluid.

THIS may help you to feel better about the transmission fluid.

And, this video (about Toyota transmission fluids) in particular...

You Tube

You Tube

There's nothing wrong with changing your oil every 5k

To side with Lexus's "recommendation" to not touch your transmission pan filter/fluid is simply absurd.

It's not a sealed unit for a very good reason.

My mechanic also has stated that Transmissions are closed units on this vehicle ( question that?) but that they would not need fluid change until the 100,000 mark.

No one said that! The OP specifically said; "The owners manuel says every 5,000 miles to change oil". This is incorrect, as the Owners Manual says to replace the engine oil and filter every 10,000 miles or once a year, whichever comes first.

Because the mechanic doesn't exactly want your transmission to last as long as it should. More money for him too, potentially.

60K is time for a filter and fluid change. Do it and thank me later.

Are you suggesting that you know better than the Toyota/Lexus and Aisin Transmission engineers/designers?

I am suggesting that Lexus engineers don't give a flying s*hit what you do with your transmission because one way or another having the gearbox fail (which will almost always occur well outside the warranty period) will result in more money for them. Whether you have the transmission replaced by them (so that they can attempt to refurbish the broken old one), or you have your local mechanic rebuild your existing unit, or you're the loyal type who sticks to Lexus and decides to get a newer one, more money is being drained from your pocket which is what they want. If you asked the engineers at Aisin, I guarantee they will say the exact same thing I did. After all, the transmission contains a serviceable pan filter for a very good reason. BMW also says their ATF fluid is lifetime, like many other manufacturers, but go on ZF's website, and they literally don't stress enough how important it is to change your filter and fluid by the 60-70K mile mark.

Failure to care for your transmission WILL lead to eventual and catastrophic transmission failure down the road. Failure that could have been completely avoidable. You can't just sit there and argue that transmission fluid is not a serviceable wear item. The magnets at the bottom of the pan filter aren't going to hold those metal shavings in place forever...

As an engineer, I must be doing something wrong. I don't get paid more money when the parts I design fail. In fact, it gets pretty ugly.

Are there other items that definitely need attention prior to the 80,000 mileage mark on the 2013 GS 350 f-sport.

But you do design it with certain constraints and lifetimes in mind. If you were instructed that the life of the vehicle is 150k miles I'm sure you will not be designing it well past 150k miles increasing costs etc. I don't see how changing the transmission fluid too early would be bad unless you're putting sand in there. It's like cheap insurance.

Correct, everything we design has an expected service life. We also use MTBUR (Mean Time Between Unscheduled Removal) and MTBF (Mean Time Between Failure) in our designs. If my designs are not meeting those requirements, my employer doesn't go "it's okay, we're happy to sell them a replacement". Rather I get assigned work to get back to it, figure out what's going wrong, and fix it. So I would not agree that engineers don't care when parts fail and that they somehow get more money if their designs fail. If our designs fail early, we lose customers to our competitor. Ultimately, that's less money for us.

So to be clear, I am not arguing or stating my position on the value of changing the transmission fluid. I am stating that I disagree that engineers don't care if it lasts the expected service life or not.

Oh for sure I would expect all components to last the expected service life. I think the question for some of us is how long that expected service life is and if we keep it for well past that how can we prolong it. As for my Lexus cars all of them have over 130k miles now and one has 250k at the moment. I'm sure manufacturers don't intend for their vehicles to go this long but I definitely try to push the limit on usage and would to keep it past its expected service life. My 2GS with over 250k miles on it did require some transmission work around the 180k mark and my sisters ES was starting to shift really rough around the 150k mark.