I have an 07 RX350 with 69,000 miles. Can I safely switch to synthetic oil?

Hate to say yes for tales of oil leakage as synthetic is so slippery, it slips on past the gaskets, all I can recommend, is that you try it once, placing a sheet of cardboard where you park, after a few thousand miles take a look at the intake manifold to see if it's oily...if yes, then discontinue and go on back with the stuff written on the hood label.~

Switch any time you want. It is true that sometimes after switching, there are more leaks. That's because the additive package is different and the synthetic oil has less stuff that makes the seals swell. Read about it here: http://www.bobistheoilguy.com/

Check you cost of synthetic vs conventional oil, you must still change oil at the recommended intervals so no savings there. Plus you do run the risk of an oil leak where none existed before.

Thanks for the answers! I'll also check with my Service writer at the Dealership.

I have been using 100% synthetic oil in all of my cars since about 1978 and have never had a problem that I could contribute to the change to synthetic. I buy only used cars with high mileage. The last 2 were a 95 V6 Toyota Avalon I drove from 80,000 to 212,000 without needing engine work and then a 2000 Avalon from 146,000 to 224,000 without problems or leaks. I have often felt that the potential leakage problem is overblown. I am a retired chemist and know and respect the polyalphaolefin base of the synthetics. Good luck.

I switched to it after the first oil change in my previous car and had no problems what so ever. I went longer on oil changes too. One time I let it go 10,000 miles and when I checked it before i changed it, it still had some color to it, it wasnt completely black like most conventional oils get after 3-5k. its much better oil and I run it in all my vehicles. never had a problem with leaks after switching

"I'll also check with my Service writer at the Dealership." -- Don't expect a straight answer from those guys. Their job is to sell oil among other things. They are not going to advise anything that will bring you back less often.

Use semi-synthetic, which is dyno oil synth blend, first. It will not create leaks as profusely. Regular oil and additive is probably just as humane.

no one will testify that synthetic oils cause leaks...alas..a wives tale~

when manufacturers recommended synth, it was back up with better gaskets and seals...or if you can play Beethoven at 90 mph

bet the aerodynamics on that "piano buggy" will start flappin' like a sailboat at 90mph~

If Edd China can make his bath tub go 42 mph...

How do we get people to stay with the questions asked?

You got it answered in the first three postings- I'd be satisfied with that, anything more is just "bonus material" like it or leave it~