Not sure where to star with this one.

Only when temps get cold and before the truck has a chance to warm up have I noticed that upon shifting into Hi-gear a good shudder sets in. When I give it more pedal and get the truck to down shift I can bring it out of the shudder, but if the truck hasn't yet warmed up and it up shifts again to hi-gear, it will start shuddering again.

Ideas on what to take a look at would be great!

 

Pretty classic signs of injectors getting tired. You can pull the valve covers and see which one it is by starting it cold and watching the oil discharge. The weak one won't have much, if any, oil coming out.

 

Any chance that there is anything else I can check, clean, do to resolve the issue or is it plainly and simply injector degredation?

Changed oil this week, then armer temperatures hit, also added some diesel clean 911 in a healthy dose.

I have not been one to use any kind of additive in fuel or otherwise, assuming the injectors are as old as the truck (2002), I think I'll start and see if the issue clears up at all through thte winter.

Lessened shuddering this morning, and odd that it occurred with 60* temps outside.

Any more ideas?

 

Sometimes 5w40 synthetic oil will lesson the problem. You can also leave it plugged in all night so the oil is good and hot and see if it makes it any better. That would rule out anything not engine related since the block heater is only warming the engine.