I'll tell you I was two licks away from grabbing Maxlife synthetic to throw into my 45k mile V6 Tacoma.
Just bought it 6-7 mnths back and had been running the GC 0w-30 in it; well the GC has become VERY hard to find in Colorado since then. So, we were on the fence as to which oil to run in it as we were very adament about wanting to stay with GC, being a true synthetic.
I've heard and witnessed true benefits of the Maxlife regular and synthetic in an older truck, but thought to give the Castrol GTX a try first and see how it goes.
I will do a 5k oci, if all feels good during that time, I'll run another round of GTX then do a UOA.
Went off the comments of other 3.4L V6 Tacoma owners and what they felt did good in the engine.
Once it's out of warranty however, I'm tempted to run the Rotella synthetic 5w-40 diesel/gas oil in it for 7-8k miles easily I'm sure.
If I had Volvo's, they'd be running the Rotella synthetic - excellent oil for the price.