Hey guys. Iv owned my Excursion since February and it has been an excellent rig. I have zero regret buying it so far (knock on wood).

The previous owner made it sound like it had been meticulously maintained. He installed an EGR Delete, coolant filter, flushed the coolant (because he put in green instead of gold), and replaced the injectors a year ago. After starting some maintenance myself, I found the coolant filter was FULL of crud, fuel filters were filthy, and the water-in-fuel light was on. Symptoms of not-so-much maintenance... So after the fuel pump took a crap, I installed a new HFCM and replaced the coolant filter. I also bought one of those OBD scan tools that syncs with your phone to monitor the engine as well as I can. Iv noticed something a bit concerning: my EOT will easily reach 230* while my coolant stays at 186*. That's 100% unloaded, flat terrain, and even at 40* ambient temps. So far the highest Iv seen is 242* IIRC. I talked myself out of it being a problem after seeing some guys reach higher than that EOTs pulling campers uphill and the fact my EGR cant go bad. I'm really just looking for some closure. I will end up replacing my oil cooler someday, I just need to know how soon. If its not a big issue, Ill put it off awhile.

Thanks guys!

 

First and foremost ECT is too low you need to do two things
Cold soak test of EOT ECT check in morning the should be within 1-2 deg of each other, if not replace the offending one or both.
you can also check by swapping the two sensors. if the readings end up being the same you need a new thermostat.

when you get that figured out and the ECT reads at least 190 then you can see if your Deltas are in specs 0-15 degs. If too high time for new oil cooler, which is an easy but time consuming job.

 

I'd seriously flush the cooling system and then change the thermostat AND the oil cooler. 44* delta is too high even if the ECT is only 6 degrees low.

 

And the coolant temp will drop with a very clogged oil cooler as it's not pulling the heat out of the oil.

 

This ^^^^^^^^^^^^^^

 

At 253* the truck will de-fuel trying to cool itself, with the EGR delete your not worried about the EGR cooler rupturing but the EOT is high. If you were to tow, I'd bet you hit 253* and that would not be good as the internal oil temp is probably much higher.

Save your money, changing the cooler it is just around the corner. As suggested, chemical flush it first to remove anything else the installed oil cooler missed as they are great filters, you don't want the new one clogged again.

 

Alright guys, you've given me some insight. Ill start planning for an oil cooler. Iv always thought the deltas were way too far off regardless of whether I have an EGR or not.

So your also saying my coolant temps are low? Iv noticed the heater takes forever to catch up in the winter and was also planning on the mishimoto 200* thermostat.

I'm going to also change my oil this month + HSS to help with some other issues. Its getting time to catch up on maintenance lol

Thanks guys!

 

I've run 242 this year while towing a 30' camper and 253 last summer while towing a 30' camper. I changed the oil cooler and oil cooler cap this winter.

Unloaded, I presently run a delta of 6. 65 mph, level road, all warmed up.

Don't tow with it, but you will need an oil cooler. Run synthetic oil because it will withstand the heat better.

Do a chemical flush and drive it for a thousand miles or so first. If you don't have a coolant filter on now, put one on and drive it for 1000 miles before doing the oil cooler. The coolant filter and oil cooler will act as filters to get the junk out of your coolant system before putting in a new oil cooler.

Keep and eye on the oil temps cause a flush can loosen things up and cause them to lodge in your oil cooler.

 

Chemical flush will probably finish the cooler off by plugging it more. I'd be ready to replace it very soon after the chemical flush... you may not make it a 1000 miles before hitting the wall....253*.

Coolant temps are low because the flow is restricted and the heat transfer isn't happening as it should... downfall of a plugged oil cooler.

 

Alright. I was wanting to save up and get the Bulletproof cooler buuuut you know how that goes... big dreams small wallet

Ill definitely swap the coolant filter when I change the oil this next time. Its hard telling when I will actually come across enough dough to do it. Maybe after my 7.3 sells

 

Definitely too low stock thermostats are 190*
The mishimoto 200* have lots of happy users

save the old thermostat when you swap it out, you can cut out the center section and use it when you do your coolant flushes. HIGHLY recommend flushing before you do the Coolant filter.