I never run my AC, the weather hasn't been that hot here, I've done mostly highway driving, but I do run regular gas. But I always have. So I don't know. Just seems like the quality has gone way down hill. I might try and run the middle grade and see what happens.
95 XJ sport 4.0L geared 4.10
AX-15 with an NP231
JB SYE with a High Angle CV driveshaft
RE 4.5" lift 33x12.5x15 ProComp AT's on AR 767's
JKS QD's RE HD trac bar & frame mount
Disc's on all 4 corners, stopping fast is so nice
Rusty's Airtube with K&N and Hella 500's on an ARB Bull Bar