the 3.5 has a belt which needs to be changed at 90,000. but it dosent have to be exactly at 90,000. its alright if you go over couple thousand miles, Lexus makes very good timing belts that are thick and wide. i have a rx300 that i bought brand new in 2001 and changed the belt 9 years later with 95,000 miles and it looked practically brand new and i live in an area with harsh winters. Also it would be a good idea to change you water pump while the belts are being replaced.
http://wiki.answers.com/Does_the_2010_Lexus_Rx350_have_a_timing_belt_or_chain#ixzz1ADehAfQR
In 2010 Lexus RX350's started using Timing Chain's in the 3.5 engine, which require no maintenance (unless very high mileage is reached or parts failure). Earlier years <2009 had timing belts. I verified the 2010 model has a timing chain via contacting a local Lexus parts department.
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How do you change air filter on 2010 RX 350
timing chain....
Timing chain
It has a timing chain.
It has a timing chain.
chain
Chain
yes u can, but there will be some loss of horsepower, other than that u're ok.
Timing Chain
It has a timing chain.