WOULD LIKE TO KNOW IF ANYONE HAS HAD A PROBLEM WITH BLOCK CRACKING. OUR TRUCK HAS 119,000 MILES AND IS IN SHOP NOW. CUMMINS WONT ADMIT ITS MFG DEFAULT BUT SAID IT HAS HAPPENED BEFORE
I'll take it your ISB is still under warranty with that low of mileage. Never have had a block crack on a Cummins, but have seen and experienced head cracking on B5.9's and C8.3's - usually due to overheating. Yours sounds like a defect to me.