Hey...hey...hey now lol Just cause the OP is long gone doesn't mean this thread should get locked or pushed down.
As shown, Many of us here run the 5.3/6.0's and lots has changed in the Engine oil market in last 3 years since OP asked
At moment, I have 3 LSX trucks in my fleet. Oils I currently use are in my sig.
2002 Suburban LM7 with 170K miles running my stash of Chevron Delo 400XLE 10W30 synblend. Its been at my mechanic last 2 weeks getting basic work done then getting shipped up to Oklahoma as a back up vehicle
Have only driven it 100 miles or so
2001 suburban with 320K miles. PO was running on 15K of Pennzoil conventional YB ?? 14 month OCI !! Atleast thats what jiffy lube sticker showed ?? It was TEXAS CRUDE black and had to be changed 911 ASAP YESTERDAY !! Used 32oz of GUNK engine flush and poured in some good ole Castrol GTX ultraclean 5W30 flavor as a 2000 mile engine oil break in:! She's running nice and smooth like a "baby LSX" with only 100K on it lol. Mid July next OCI I Might try some M1 5W30 Truck/SUV to see how she reacts lol
On my 01 Silverado HD 6.0 @ 155K miles. I'm Still trying to find the right oil to make my LQ4 run a tad bit quieter and smoother. Just like my crown vic police interceptor she doesn't like the Shell Rotella GAS/TRK SUV in her now
Have a decent supply of Chevron Delo 400XLE 10W30 synblend I got for $5 a gallon @ AZ and maybe 100qts of M1 misc oils Vanilla, EP, EP HM, M1 AP, Super Syn lol
Decisions........decisions
Dave