I moved from OEM p-metric tires on my previous (2008) LX to load range D KO2 and the ride was harsh. I now run load range C Toyo AT3s and find them much better on ride quality and gas mileage.
I run the same tires you have and ran a set of KO2s before the Toyos. However I switch to a dedicated set of winter tires (Blizzaks) in the winter. In extreme winter conditions a dedicted winter tire makes a difference.
I have a 2018 LX with the same tires you have and similar mileage. I can absolutely feel the difference between Comfort and Sport mode. FWIW, I run at 37 psi.
I ran 285/55/20 KO2s load range D on my 08LX, and while I really liked them, I found them a bit rough. On my 18LX I am running Toyo AT3 285/70/17 in load range C on RWs. I am very happy with this tire - much smoother and quieter than the KO2, and a bit better gas mileage too.
This probably belongs in the SQOD thread, but here goes: How do I remove this cover to check underneath/clean? Don’t want to experiment, break some clips and have a spring for a new one.
On #5 - yes you can add crossbars. I got the OEM Lexus ones. Keep in mind they only mount in set locations (where there are holes in the rails). I miss the adjustable rails of my 08.
From Dawson City, Yukon to Eagle Plains, Yukon on the Dempster Highway is 254 miles with no gas available, and yes I was able to do that distance easily on the stock tank and pretty loaded LX570.
Having said that, I am seriously considering the long ranger. Its 70 litres (18 gallons) capacity...
I had this issue with my 08 LX. Dealer wanted $4,000 plus labour to fix. I ran the truck for at least 3-4 years with the leak before I traded it in. Every other year I needed to recharge the AC with additional refrigerant, which I think ran me about $250.
No extended fuel tank, I carried 20L on a roof basket, but did not need it.
I did that trip in my 08LX, I now have a 2018. Tire size was 285/55/20 LT on stock LX rims.
Avatar is from the Dempster Highway - heading south.