When I was driving back from dinner working on a project 5 hours from home, my CRD sounded like an early 7.3L Power Stroke starting up cold at -10F. Then I was going no where with out a tow truck. A repair shop in Oxford, OH that used to be a Chrysler, Dodge, Jeep dealer got me back on the road. When I knew what happened, I called Suncoast and Erny recommended welding washers onto the Flex Plate and going to 3/8" - 24 TPI Grade 8 bolts. The shop University Motors was able to come up with 10mm bolts in a 10.9 hardness, the metric equivalent of grade 8.
Flex Plate

Torque Converter

$611.53 and I am back on the road.
After the event, I figured out how going to the larger bolts could be done with out dropping the transmission as long as they did not fail like mine did. Needless to say, I wish I had done it before it failed, hind sight is always 20-20.
1st, use a step drill or a drill collar on the drill to drill out the Flex Plate holes to 25/64ths.
2nd, using a Q drill with the end flattened, drill out the 5/16" - 24 threads in the torque converter.
3rd, using a tapping fluid, start with a 3/8" -24 plug tap and finish off with 3/8" - 24 bottoming tap.
4th, clean out hole with break cleaner and allow to dry, use compressed air to speed up the process.
5th, use Loctite (Suncoast recommends RED) install new larger bolt and torque up (50 Ft-Lb?).
Proceed to the next bolt until finished.
If you have more than an Eco Tune or Stock Tune, I would recommend going to larger bolts, Duramax and Power Strokes with strong tunes are failing their 5/16" bolts, why would our CRDs be any different?
May the Detroit Bean Counter Engineers spend a very long time in a place with the same name as a town between Howell and Lansing, MI.