GX front/rear Diff, transfer case, & coolant question

[viclava]

I am relatively new GX 460 owner 12/24 and have a question regarding when to actually service the front and rear differentials as well as T-case.  Since the GX is 4.5 yrs old and has 31,200 miles on it and it is used for short trips primarily, I was wondering if I should change the fluids.  I had it serviced at Lexus in February at 28k miles and per the service records, it was just “checked”.  I would think the daily short trip driving would be considered extreme use and those fluids should be replaced.  If anyone has any opinions regarding this, I would love to hear them.  Also, regarding the coolant.  Even though Toyota/Lexus claims coolant does not need to be replaced that early, I do not subscribe to that as I have read articles about gaskets degrading and being related to old coolant.  Thoughts?

I appreciate any input,

Cheers

[McBrian]

This is a sure way to start an argument 🤣 (kind of joking...)

With that mileage It obviously wasn't used hard before you got it. It will not hurt every few years to do fluids. #1 and cheapest preventative you can do. Something *I* personally do when I get a used car. Just makes me feel better to know I'm starting the clock fresh on my ownership.

Short trips in the car (while they sound great at selling-time) rarely get the fluids up to temp to evaporate condensation. Sitting water on metal makes pitting and rust. It is also a very poor lubricant. Make sense?

Never heard about any cooling system gasket issues in any of my time with T and L outside of truly ravaged and ignored cars. The internet is full of crap information and BS so glad you're asking in a little bit more focused place (even though there's tons of misleading stuff here as well...)

Damage from "Lifetime" fluids and "extended interval" anything netted me a LOT of money over the years. Would much rather see someone slightly more aggressive with fluid care than have to argue/explain/beg Corporate for replacements. EVERY manufacturer has transmission and engine issues because of that BS... Don't get me started on 0W oil...

An ounce of prevention and all that. You'll come out better in the long run.

[RX400h06]

Check out "The car care nut" on youtube. Ahmed is a very experienced Toyota/Lexus master technician. He agrees with some of what you've said but disagrees with your hatred of 0W oil. In one of his videos he explains why Toyota specifies 0W - X synthetic oils. In other videos, he warns against changing oil viscosity for normal driving conditions. 

 Even regarding my GR Supra, normal street driving is perfectly acceptable using the 0W-20 synthetic oil that meets ACEA C5 and API SN standards. Those who track their cars, whereas oil temps can reach 280 degrees and beyond, higher viscosities are necessary. Some owners use gas that has high concentrations of alcohol, which can dilute the engine oil during aggressive driving. 

[McBrian]

Yeah... I know...

I was part of the Camry 4cyl and Subaru engine recalls for the rings/clearance thing so it's a little triggering.

Finished my auto career with BMW right when your car(s) came out. Fun toys and another Supra is on my again list (had a 89 7M-GE that selling is one of my few regerts...)

Agreed with the harder use and fuels.

Ahmed and I would have made a very good service team. I miss the good techs.

[viclava]

Thanks gents for the responses.  Much appreciated.  BTW, I have come across Car Care Nut.  He is great.  I will have to browse his videos for GX specific videos.

 

Cheers