Dual mass fly wheel is junk. You just have to replace it with a solid flywheel and then you have a good setup. I tow at about 26k GVW with a G56 and so far no problems after 25k miles. Just got back from a 6k miles trip hauling the 5ver about 2 months ago. I really like my SBC 3250 dual disc. Even quieted down after the trip out west. Good luck and enjoy the truck.

 

we had all four of our 06's dmf fail very early and were still under waranty. we knew they would just put a new dmf back in so we replaced them with the southbend single disk conofe kit. two trucks hooked to 5th wheel's tow at about 20,000 gcw the other two pull goosneck equipment trailers, with our 710 backhoe the gcw is 44,000 lbs with very steep grades. once you get rid of the dmf you will never have any more clutch problems. the new southbend will be a little more grabby as robert said and the new solid flywheel is noiser than the dmf

 

I haul 37,000 GCVW on a fairly regular basis. Mine is an auto and I have had some troubles but If ya know what yer doin and take it easy it seems to haul quite well.

 

It's all about driving habits - as it was said earlier "get the pedal out before you hit the gas". I pull a 14K 5th wheel and start out in 1st idling then get on it slowly. No problems at 38,000 miles.

 

I have an 02, six speed with SB clutch. I have hauled 18,000 on the trailer which is about 8,000 for a total of 26,000 lbs. I have done this several times and had know problems. The SB clutch was the cure, as I went through many stock clutches prior.
Geer

 

I've grossed over 30,000# many times and never had an issue with the stock clutch or drivetrain.

Approaching 145,000 miles.

 

55,000 miles, clutch still hanging in there. I pull 25,000lbs almost every weekend. I actually prefer this tranny over the 5600. I had that on my 02 and this shifts better, has lower gearing, and is easier to drive. I know that this clutch will not hold as much power as the 5600 though. I dont want to put a super clutch in there as I did that on my 02 as it would buck and jerk taking off with a heavy load and it was just easier to drop the clutch. That southbend could handle the load and twin turbo power, just hated getting heavy loads started.