A Truck is a Truck
Rob, sorry to hear about your truck dislikes. Unfortuantely some of them are virtually built in and may not be 'bombable'.
I'm gona try to be a 'truck counselor' here:
First, it's a truck, it is designed to carry a heavy load. So it is going to be rough riding SOB when empty. It should and does ride good with a light load, so put a light load in it most of the time, a stack of plywood or drywall under cover should do the job. Or a 4'x8' sheet of steel! [extra heavy-duty bed floor protector!]
When you put your camper in the bed, it sounds like it is down on the overloads, take a look and see if it may have too little suspension travel remaining, and is hitting the stops. I doubt it, but it is possible.
I'm green with envy over your 19. 5" wheels, must look great, but I'm sure they are contributing to the rough ride too. I'd run them at as low a pressure as you can when unloaded, or else they will shake your fillings loose. They also are designed [I'm pretty sure] to carry a much higher weight than they are carrying on your truck.
For the transmission, I think some CTD owners have found a different trans lubricant that helps with the shifter feel. A synthetic motor oil I think.
Now, for the real problem: Turbo Lag! I'd take that HX-40 off and either sell it, or send it to one of the turbo gurus to get it modified for better spooling. Put the HX35 back on, and drive the truck. Driving a stick with big time lag IS enough to make you HATE your truck.
You may have higher egt's with the smaller turbo, but just turn down your fueling box. In fact I think your twitchy throttle is from the box being turned up too high. You'll probably like driving your truck with less maximum power, but with more driveablity.
I have BD3's, and a Piers 'Nasty Nine' turbo, and Edge Comp box, [not the HOT box yet]. My turbo is a Piers-modified HY35, and is very small, and fast spooling. And yes I can see temps above the recommended max, but NEVER when just tooling around with the box set on the lower levels. I have to have the box turned up and hammering it to get high egt's. Off the line boost is very fast, and smoke is there, but not too bad.
I know you are at higher elevation than me, and this will have some effect on egt and smoke, but you don't have to live with that awfull lag. a bit more tuning and swapping of parts should make your rig drivable again.
I'd be in severe depression if I hated my truck! Just check with Steve StLaurent aka: Minivan Man, or Soccer Mom, he's really bummed to be driving a gasser grocery-getter [loaner vehicle] instead of his truck!! We should have his trans back in soon.
EDIT: Steve has his truck back as of Midnight sunday night the 19th. He's grinning BIG TIME!!!
Trashcan that HX40 and live with some occasional high temps!! Or cough up the extra bucks and get the 12cm B1 turbo, at least you'll smile again!
Ok, the hour is about up, no payment required, this is a freebee, just report back with a progress report.
P. S. all kidding aside, I hope you find a fix for a few of your truck's ills.
Greg L