No, it has a timing chain.
The Lexus GS300 qualifies as a midsize sedan. This is a great car, and it has only improved with each new generation Lexus has released. Its latest design was in 2006; however, the 2006 model was discontinued after a year and then rereleased as the GS350. Lexus made the GS350 in a response to the consumer complaints about the lack of power in the GS300. The GS350 was released with a 3.5 Liter V6 engine. Both the GS300 and the GS350 are identical except for the beefed up engine. Hope this helps.
PLIZ HELP How can i reset the injector maintenance required in lexus gs350 2012
http://www.clublexus.com/forums/showthread.php?t=338155
The 2011 Lexus IS-250 is 15 ft. 0.3 in. (180.3 in.) long.
The 2011 Lexus IS-F is 15 ft. 3.5 in. (183.5 in.) long.
The 2011 Lexus IS-350 is 15 ft. 0.3 in. (180.3 in.) long.
The 2011 Lexus LS-460 is 16 ft. 7.2 in. (199.2 in.) long.
The 2011 Lexus CT-200H is 14 ft. 2.1 in. (170.1 in.) long.
The 2011 Lexus IS-350-C is 15 ft. 2.5 in. (182.5 in.) long.
The 2011 Lexus RX-450H is 15 ft. 7.8 in. (187.8 in.) long.
The 2011 Lexus GS-450H is 15 ft. 10.7 in. (190.7 in.) long.