It looks like the only difference is that the Napa oil lacks the CH-4 designation. CH-4 seems to be needed for diesel fuels containing sulfur, so maybe it isn't needed in gasoline applications?Yawp, so apparently this stuff is all gone.
The old Honda Shadow needs an oil change. All my bikes have been getting T6.
Would NAPA Diesel 15 40 be the same thing?
Nothing. We got T4 though.
Just FYI, the Walmart in Claremont NH had a shelf full of T6 on Tuesday morning this week and I grabbed two gallons.You can order online and ship to store for free at Wallyworld, FYI. There's never any T6 at my local store, or the high zinc classic, both of which can be bought in gallon jugs and delivered to a pickup locker.