Recently there were 3 EOT higher than normal threads going on at the same time. This got me to thinking about my truck as it seemed to run hotter after an overheat situation several years ago. Never bothered me but these new threads got me thinking about it....along with some other thoughts

I also has a recent encounter with a cow which forced me to replace some items that were damaged. Upon removal and deeper inspection, I decided to replace some items.
AC condenser was damaged and needed to be replaced. After removal of condenser, I noticed my 6.0 tranny cooler was tweaked and rubbing on the intercooler. I also noticed my 6.0 power steering cooler/ lines had been leaking and causing issues with oil/ debris build up on intercooler, tranny cooler, etc.
I also can't remember when the last time I heard my fan clutch kick in...so time to order some parts...

I ordered a CSF condenser, Motorcraft accumulator/ Dryer, orifice tube, AC lines (not motorcraft, regrets), Motorcraft Fan and Clutch, Dieselsite 40 row tranny cooler. I was at my friends place looking at parts trucks and noticed older trucks came with all aluminum intercoolers unlike my plastic endcap version. So I pulled an intercooler from a truck.

This past week or so, I pulled everything out and prepped for new parts. Cleaned and tested all aluminum intercooler, cleaned rad fins and installed all new parts. I didn't get to the fan/ fan clutch until today.
Got my AC working better than it has in years (probably due to overdue condenser and crushed fins).
I think the new fan clutch I could faintly hear until it got close to operating temp; then I couldn't hear it anymore and definitely not like the original.

Conclusion: Prior to the fan/ fan clutch today, I was able to do some test runs and gained around 5* cooler EOT but ECT remains unchanged. After the new fan/ fan clutch, not additional change.
I have to do some more test runs but the Dieselsite 40 row tranny cooler doesn't seem any better than my 26 row OEM 6.0 cooler. I am also curious what bypassing the tranny cooler in radiator contributes. I've heard to keep it going through the radiator and I've heard to skip the radiator
Right now I have it going through the rad cooler and temps have been 140-150 with ambients in the 70-80's. Thats about what it used to be and I haven't done any hard runs yet...but it seems to be in-line with the 26 row 6.0 cooler.
Just thought I would share my little journey/ findings

Here are some pics from my cow incident as well as what I found when removing parts

 

I would keep the trans cooler in radiator if I were you. Generally the cool side of the radiator is a decent amount cooler then hot side. Check temp different between top and bottom of radiator next time where your checking stuff out.

 

I think I remember Mark mentioning to leave it in as it also helps get the temps up in the cold. But I'm old and my memory doesn't always work the best.

I was feeling a bit dubious about my fan clutch, but we've had some hot days lately here in PHX - and I could hear it kick in at the stop lights, not super roaring loud but def engaged. Not sure what temps typically kick it off but it was 104 ambient and would quiet down after I got moving again.

What temps are you seeing? I don't imagine your temps are high but sounds like you do have some altitude.

 

Before my son overheated the truck to failure years ago my ECT gauge would read around 200*. Since getting the truck fixed from that incident it has been running at 210* according to the gauge but cools off when idling. My engine has been replaced and rebuilt since then...probably around 5 yrs ago IIRC.
Currently my ECT gauge reads 210 still but gets to around 203 at idle...I should also mention that I run the Dieselsite 203* t-stat.

I never monitored my EOT's until I saw those recent high temp threads and picked up a CTS 3. Prior to the parts replacement, I was seeing up to 227* while cruising on the highway at 70-80mph, now I'm seeing up to 222* so far. this is with ambient temps in the 70-80's.
I have seen my ECT's peak at 220* according to my gauge. I will eventually replace my gauge and/ or use a EAS temp sensor through the CTS. For reference, My current temp sensor is on the side of the water pump which is near the factory sensor I believe.

Thanks...yeah I recall Mark or cleatus mentioning something like that. but I have seen somewhere that it's also recommended to bypass it. I wanted to try both ways and see what differences I might notice...with both getting up to temp as well as maintaining operating temps.

I also know/ heard 140-150* is still not quite warm enough for optimal operating temps IIRC. In the winter, I think it stays below 140, which is not ideal. I don't drive much anymore and I've had the 6.0 cooler for over 12 years without issue, so I think I'm fine.

I do think getting things cleaned up may have helped my temps some. I didn't mention it in my OP but for a little while now(few yrs), I've noticed my tranny temps a bit higher than they used to be. I'm thinking that was because of the leaking PS cooler causing oiled blockage as well as my original condenser being so beat up...time will tell

 

Much to consider here. My first takeaway is EOT is king. We are lucky to have it when possible. ECT from the dash or otherwise is downstream of EOT.

That new setup rocks!

 

IF,
I lived further north, I would have run my 6.0 new cooler thru the Radiator.

But, here in OkieLand, it doesn't usually get cold enough to worry about it, and with the OEM radiator being 22 years old, I elected to bypass it.

even so, the TFT has never run high, and I have several trips towing from Utah to Oklahoma, and once down to Georgia..... the usual mountain high passes and flat hot humid areas...

I have the Hayden Fan Clutch, I never hear it on startup like I did the OEM clutch which always roared so loud, nothing else could be heard.. glad that noise is gone.... the Hayden seems to be doing what it should, as the EOT never gets high enough for me to get concerned,

this is the hottest I have seen things.

 

I think that cow did you a fatal favor by the looks of all that gunk in the pics!

 

yeah, I probably wouldn't have noticed otherwise or for a long while. It wasn't leaking or dripping that I could really notice

 

Keep it (in my opinion). Oil-water cooler is much more efficient than Oil-air. I believe it was the e99 that didn’t include the in-radiator cooler which was promptly added back in. From reading Mark’s posts over the years, adding it back in was intentional to help reduce trans temps. When sitting still or going slow there’s not a lot of movement through the air cooler.

Mark has also stated that the radiator heating the ATF is a myth which he knows due to testing.

 

Conversely, and I’ve never had the opportunity to be involved in such testing, how does it help with cooling? I can tell you that my 2000 Excursion came without the trans lines running through the radiator. When I got my new trans back from BTS, I installed the 6.0 cooler that he provided and did not run the lines through the radiator even though I was provided lines to do so. I reckon some were plumbed that way and some weren’t. Off subject, but I didn’t have an AE injector in the number eight hole either! I don’t think I’ve ever seen my trans run over 170 degrees or so even when towing and most of the time hardly over 160 degrees.

 

I can believe the part about not helping warm up the tranny, but not so sure about it's cooling capabilities....I do faintly recall older vehicles always running through the radiator with no additional cooler.

 

I don’t think they had an air to oil cooler on those.

 

I went out to my buddies today; 30 minutes ea way. Ambient was in the mid to low 60's today.
Tranny temp never made it above 140 and took 20ish minutes to even reach that temp doing 65-70 the majority of the way. EOT made it to 223/224* then dropped back to around 219* IIRC. ECT maintained 210*
Fan clutch could be heard when I first took off until it reached around 180*, could have been sooner. I also heard the fan clutch again when I left my buddies. However it has not helped operating temps at all.

I have never been concerned but recently has been the only time I have monitored it or studied the behavior. I do feel like the operating temps are higher than they should be though.
I might be taking my RZR out riding next weekend. It doesn't weigh too much but will be going up to around 8500-9000ft in elevation in comparison to my normal 6500'...so we'll see. I think the temps should maintain as it's never been an issue even going up to well above 10k' and hauling 7k or so through the mountains

 

If it were me I would swap out the 203 thermostat and put a 189 mishimoto thermostat in it. I've never been a fan of the hotter thermostats at all.

 

Didn't we have someone here recently that was having normal coolant temps, but high ect? Ended up being the water/oil cooler..?