Any advice on what to look for/avoid in a 3rd gen gs350? I知 looking at a 2008 gs350 rwd is that reliable?

 

I bought the 2007 model new and had to take it in about a dozen times for various LSBs. I actually missed the last 4-5 LSBs originally as I had moved and never got the letters but fortunately NY state mandates the fixes so my local dealer applied them in 2017 at no charge. If I was buying a used 3GS today, I would avoid the 2007 as there is a risk that a lot of the LSBs were missed. Try to get the newest 3GS possible.

Also if it's burning oil, VRP 5w30 will fix it but only if the cylinder walls aren't scored. So ask your mechanic to check the cylinders with a boroscope during the PPI.