Looking for opinions...

I have a 1999 RX 300 with 63,000 miles. It's in mint condition, and I have no plans to ever sell it.

Given that it has plastic radiator parts, should I consider preemptively replacing the radiator? We use the car for 2 - 4 hour trips on occasion (lots of cargo space), and I would like to avoid mechanical damage or getting stranded.

- If it fails, is the design such that coolant could mix with the transmission fluid?
- Is the typical failure mode small cracks/small leaks, or is it something more catastrophic?

The upper radiator support makes it difficult to see the radiator to look for discoloration, etc. I already had the upper and lower hoses replaced. Heater hoses, thermostat and radiator cap are already on the to-do list.

Thanks!

 

If your concern is plastic top developing a leak, iyou will only loose coolant.

Typically you develop pin hole leaks which produce white powder spray pattern.

I would not preemptively change radiator. If there is an indication only then.

Salim

 

If the coolant was kept fresh and you used Toyota SLL then the rad is likely still in good shape.
Oil cooler has to rust out and cause cross fluid contamination such a failure is rare.
Top tank cracks and fails, gasket between the tank and aluminum core goes bad I see this far more than the tank cracking. In hot climates the tank tends to crack first.
This is what hides problems from so many people, the rad leaks (tank to core gasket) and coolant evaporates before they see an drips on the ground so they assume no issues. Never use anything but Toyota parts for the thermostat and radiator cap. Actual Toyota parts don't buy from Amazon or Ebay.

 

Koyorad site shows that there are 2 thicknesses of radiator available; 5/8" or 1" for RX300 depending if your car has tow package and which may affect decision,
https://koyorad.com/product?s_make=l...99&s_freeword=