Yep, the easiest way to accomplish monitoring the oil temp and coolant temp is with the electronic monitors that connect to the OBD port.
Scangauge2 can monitor a bunch of stuff that can come in handy with troubleshooting, should you have an issue. Fairly cheap too.
You would monitor the EOT/ECT for the temperature differential (AKA: delta) between them. Typical test is to get the engine up to normal operating temp (ECT 190°F give or take a few degrees). Then hit the highway, set the cruise for 65MPH, after running it for about 10 to 15 minutes on a relatively flat section of highway, you would note the delta. If this delta was to be 15°F, this points to a plugged oil cooler. The plugged oil cooler slows the coolant flow to the EGR cooler. The slower moving coolant will cause the egr cooler to overheat, and eventually it will fail internally.
The leaking coolant from a failed egr cooler can result in popped head gaskets.
The leaking coolant takes one of two paths, depending on the circumstances. If the truck is running, coolant would be forced towards the front of the cooler, up against your EGR valve. Once that valve opens, your engine takes a big gulp of coolant into the cylinders. The coolant will turn into steam, raising cylinder pressures beyond what the crappy head bolts (the TTY variety) can withstand. This allows the heads to lift and...there goes your head gasket.
If the truck is off, the coolant will flow into the exhaust manifold on the oassenger side. The coolant will flow into whatever cylinder happens to have the exhaust valves open, and when you go to crank it, this can result in hydrolocking.
Also, while your truck is running, and the egr valve is closed, the coolant is flowing out of the exhaust. It enters the up-pipe previous to the turbo. The coolant mixes with the soot in your turbo and creates a gunk that will effect the free movement of your turbo vanes. Underboost and overboosting can occur.
There are instances where the oil cooler fails. This will dump oil into your cooling system, which would need to be flushed out post repair.
The flash that will monitors the ECT/EOT delta sets the P012F code when the computer detects a 15°F delta. (I believe this flash was for 06 and up trucks, but I might be wrong)