Hi
Would you recommend the 5w-30 R&P for the 5L or stick with a 5w-20?
I have been using Penzoil Ultra Platinum 5w-20. I live in the northeast.
Just my $0.02, however, I would not recommend changing viscosity without first doing a few oil analyses. I am about to do my second Used Oil Analysis after switching from 5w20 Liqui Moly to 5w20 Valvoline Full Synthetic Advanced.
I use Speed Diagnostix though AMSOIL (they use a third party lab) is less expensive and pretty thorough including oil [fuel] dilution; not sure if Blackwell tests for fuel dilution now? I choose Speed because the results are very clearly explained along with clear recommendations.
Essentially, I am using less expensive oil and more expensive testing. I intend to change oil if necessary and keep pretty normal oil change intervals of approximately every 5,000-miles. Doing my second Used Oil Analysis (UOA) soon; just shy of 3,000-miles to see how the Valvoline Full Synthetic Advanced is doing.
You can ask others, or know for yourself through empirical testing. There's guessing and there's knowing.
My first UOA is attached in case you are curious what it contains.