Glad to hear it.
I've been swamped in the shop lately(this is the earliest night I'v had in quite a while), so I haven't been able to write up the next portion.
But, feel free to ask any questions and I'm happy to answer them.
A couple things I forgot to mention-
1. Every truck gets a pre work diagnostic unless the truck is unreadable and/or will not safely run.
2. If the truck runs without causing damage-we do one or more cooling system flush(s) prior to work that includes oil cooler replacement.
Back to point 1.-This will help you from being down and waiting on parts while the truck is torn down. Often times due to age and wear and tear, by the time someone brings their truck in for headgaskets, it is in fact hurt in more ways than one. Most guys will just keep adding water or coolant until the truck starts to run poorly. It may be because the gaskets are absolutely torched, however it is often because a sensor finally died or they hydrolocked it, or it finally mixed coolant and oil, etc...
An example of this is a 6.0 truck that I just completed. The truck was brought in for headgastkets, but by the time the client brought it in, it would barely start without burning up the starter and had ecm communication issues. due to the ecm issues, the truck could not be scanned. So some things were diagnosed based on experience and some things could not be diagnosed easily (sensor readings, injector balance rates, etc...)
Back to point 2.-The cooling system in these trucks can be a real pain to get clean. One that has had oil intrusion is actually not that difficult to clean up. We have a few tips and tricks for that. But, a cooling system with heavy silicate and/or rust deposits is tough and takes a bunch of flushing to get clean.
By flushing the system one or more times prior to oil cooler replacement, you have a much better chance of not immediately clogging up the new oil cooler. Often times people don't flush the system at all and just add coolant after work. Many people get away with it. But, I have seen a ton of oil coolers clog up in short order.
Others will wait and do all flushes after the work is done, this is way better than no flush at all, however you may have already pushed a ton of sediment, silicates, and rust into your new oil cooler. This can usually be seen by monitoring the temperature delta between oil temperature and coolant temperature.
If you have the time and the truck is running well enough to not cause damage to the engine, do a flush(or multiple to get out ass much "debris" as possible, prior to dissasembly. With additional flushes following the perfomed work.
If you have a blown egr or oil cooler, then this is typically not a viable option and you'll just have to do post work flushes. If that is the case and your coolant has quite a bit of debris in it, you may consider buying two oil coolers. One cheap one(dorman,XDP,etc..) and one good one (Motorcraft is my preference).
Install the cheaper cooler while doing your work. Perform flushes on it until the flush comes out clean. Then install the Motorcraft cooler and pour in your coolant. I have a few good used coolers in the shop that I will use as the "cleanup" cooler to save having to buy two. Then install the Motorcraft after.