Lift Pump not working

[dhirocz]

You said it's a 2011 T660 but a 2010 ISX. Two different engines. I've seen an early 2011 with a cm871 but never a 2010 with a cm2250. You sure you didn't have a valve cover switched out on it or something in the past? Does the s/n on the block (passenger rear behind the oil cooler on a flat pad) match the one on the valve cover?

...rawze got it first. A 2010 with a cm2250 would be kind of a unicorn, wouldn't it? I had a friend of mine with a cm871 in an 11 T660. That's odd.