Used 150k mile 2004 Lexus 470

[Therman12]

I just purchased a used 04 GX with 153k miles. It wasn’t taken care of very well but bought it at a decent price. In its first 150k miles oil changes were done at places like jiffy lube and quick oil changes. Doesn’t look like there was too much work done. It’s a single owner but they weren’t on top of maintenance. The water pump and timing belt were replaced at the dealer. I’m taking it in to get fluids and everything else replaced. My question: is it too late for this Lexus to make it over 300k if I take care of it from here on? Is the damage already done from the first 150k? Thanks.

[RX400h]

The Car Care Nut, a Toyota Master technician on Youtube has stated that extending the oil change intervals beyond 5000 miles will almost certainly shorten the life of the engine. Without knowing the brand, type, and viscosity of oil and brand of oil filter, it be impossible to know how long the engine and transmission will last, even if you know the frequency and mileage at each oil change.