C15 Camshaft problems?

Was running a 475, now 550. Leased out, and run 80,000 gross now, but previously hauled grain with a '96 W900 and RTLO16713, and very strong 475 3406E.
I know quite a few people who run 475s flashed to 550, with the 1600# trannys. Hauling grain, most of us had the 100,000# permit, which to a Cajun, means 100,000# in the trailer. When loading in the field, and coming out with those big loads, you know things were in a bind. The only time I remember a disaster, was a fellow who had purchased one of my fathers Volvos, with a stock 12.7, 470 Detroit. He was easing out of a field near Waco TX, when the trans disenagrated, but this fellow could manage to break a ball bearing in a plowed field.

Repair shop stated that my failure was due to low / no oil in trans, or flooded with engine coolant from the heat exchanger, as the shafts, and bearing that gave up were discolored with blue heat markings.

 

Thanks to you, Jas, and the others for all their advice, and help. Should do a separate post thanking everybody, but I'll do it here. I'd probably still be pulling hair, and walking around mumbling like an Evinrude outboard motor if not for you guys.
I'd like to especially like to thank DDS, who went way beyond just flashing an ECM for me. He took the time to locate one, flash it with my configurations, and ship it from his location in Canada, to me in Louisiana, following up with countless phone calls to help me get up and running. The amount of time he devoted to my ordeal made me feel like I was his #1 customer.
Also would like to thank Rockhauler for his calls and time.
Nice to know there are still a few of you'll that care!

Jas, I had no idea about the "splash/pressure" lubrication being the only difference in a 1600# and 1800# trans. Mine was done by a rebuild shop, curious now, and will call to see if the mod was done, it wouldn't have saved mine, but it would add a little piece of mind, IMHO.

Something I was told, which I want to share, the rebuild guy told me that #1 cause of catastrophic trans failure was low/no oil;
#2 was engine coolant getting in the trans.
He recommended going to an air cooler that bolts onto the back of the trans, said Pete dealers offer one, but he didn't know the cost.
Might not be an option for you guys running the really cold areas, but sounds like a good idea for a "warm weather wuss" like myself.

 

What I did, was disconnect both steel lines going to the box behind the fuel filter housing, I then cut the line that comes from the turbo, and routed it into the head where the short line used to connect to the head from the box, basically eliminating the box, and the short line. I haven't plugged the fittings on the box yet, (darn special fittings), but I don't think the box would have any effect on my boost, as no lines are now connected to it, and ECM is now a 6NZ.
I'm kind of wondering if I should disconnect any wires, such as the fuel temp plug on the filter housing. Seems I vaguely remember reading something like that when converting MBN to 6NZ, but I could have been dreaming.

Cat from the valley, do you remember how much of an increase in temps you experienced when switching from the coolant to the air cooler?
I run mostly in home state of Lousy-anna, where it is pretty hot also. The coolant hoses have valves on them at the engine block, and both are shut; Was like that when I purchased the truck, and according to gauge, trans runs plenty cool, barely above 150 degrees most times, so basically, I am running without any external cooling. I'm thinking that adding any sort of cooler would only be an improvement, and insurance.