Originally Posted By: opposite_locker
Recently switched over to GC (Syntec 0w30) in my '08 Ram 4.7, and have noticed a few improvements over the previous oils used (M1 0w20 & PP 5w20). Cold valvetrain clatter is still there, as it was with M1 & PP...must be an inherent characteristic of this engine. But when warm, the valvetrain is considerably quieter with GC and the engine does idle a bit smoother.
OCI with the M1 was 7500 mi, and 6k with the PP...am thinking will run the GC for 10k miles, with a filter change & topoff at 5k.
I believe the Castrol Syntec 0W-30 is only API Service Level SL. You are supposed to be running an API Certified 5W-20 oil with the Starburst symbol which would require it to be API SM among other required factors. So not only are you running the wrong weight oil, plus the wrong certification(s), you now want to extend OCI's to 10K when 6K is the max Chrysler allows for?
For whatever it is worth, from a former dealership parts and service guy( have worked both ), you are creating a recipe for hassle and out of pocket expense should you have any engine problems. You already have valvetrain noise, which BTW is not a super common 4.7L trait, and now you are going against 3 specific owner's manual requirements set for the by the car mfg.
Just something to think about. I would try some different 5W-20's. You could get away with an 0W-20 in winter but at least make sure it meets all the spec's and change it on time.
Good luck with the truck. BTW - how do you like the new 310HP 4.7? I had an 03 Ram w/ the 235 HP 4.7L and it was a decent enough engine but vastly underpowered for the heavy truck. Sold it for an 04 HEMI Ram which was much better. Now I have an 08 HEMI and love it as well.