Cummins ISX engine oil?

[Ricky]

So just some F.Y.I. I let the Speedco check my boxes and grease truck and trailer. So when I was cashing out I asked the guy if they were having trouble getting T4. He said that they haven't had T4 in months and have been using T5 instead. I have a friend who uses them for oil changes and he has a 07 ISX. I told him and he called and asked because he was fixing to go there. So he ended up scrambling to get enough T4 for them to use his oil. Also check the small Walmart gas station in your area. I bought 22 gallons from just one place. But if you use any place ask what oil they have.