Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
Got the new Spek oil temp gauge in last night... Im so sick of running & sodering wires.:baby:
I hope to add some quality test info as well. Im very curious to see what the oil temps do in the cool climate up here, something tells me they still get pretty friggin hot. Thanks for all the info guys. Sharing is what gets us to the next level. :hug:
 

Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
Not sure yet... Might pull a 27ft enclosed down full of house hold goods, not committed yet.

Depending on the job market, maybe pull a 32ft enclosed back to Fairbanks for me to move with:D
 

chevyburnout1

Fixing it till it breaks
Aug 25, 2008
2,368
1
38
Berthoud, CO
Sunday I may be heading out to Nebraska to pick up a car for my buddy. No big hills unfortunately but I'll probably be using the heavy gooseneck. We'll see how things turn out!
 

adeso

wait, what?
May 30, 2011
1,569
0
36
Minot, ND
Just some feedback, around town I never see above 195ish, I was seeing 210 just driving around with the AC on before. I get it up to 210ish messing around, but have yet to tow with it yet to really see. I’m very happy with it for sure. Running syn oil, Valvoline I think. slight drop in oil PSI cold (but who cares its still almost maxed out), but the middle temps it seems to be the same. And it doesn't get hot so it stays where it should.
 

super diesel

<<<< Under Pressure
You'll be happy with it towing Andy. You'll look at the gauge and say "wonder what it was without the cooler?"

Have any pics of your finished set up? Did you enlarge the air dam?

I roll with my camper on most the summer (always ready) with the A/C on. It was 93*F out today and around town I was between 190*F and 205*F at 12 1/2K lbs. Mostly empty right now.

I talked to a heavy diesel mechanic friend of mine and told him about the trip up the grades. He was astonished to hear I held the oil temps to only 246*F up the back side of Eisenhower with 20K and holding the speed limit. He said the big rigs are always up in the 300*F+ range coming up it and that he loved that trip because he got A LOT of motor work from them afterwards. :eek:
 
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adeso

wait, what?
May 30, 2011
1,569
0
36
Minot, ND
I need to cut on it some more, still blocking some airflow. I also need to go back and fix that stupid lower bracket that isn't straight

cooler.jpg
 

super diesel

<<<< Under Pressure
Wouldn't really notice it till you say something. Doesn't look to be restricting any air flow. See the LLY I have here doesn't have the opening at all. Going to have to make something like a big opening and heat gun it. Then I'll have to put an aluminum bracket on the plastic where I cut it open (two sides and the top cut and bent back in to direct air flow) to make sure it keeps directing the air the correct way and not push back in further at speed. I'm curious to see what I end up with. Need to do something soon because it's getting hot out.
 

super diesel

<<<< Under Pressure
Had to hammer down in the "Cooling while towing" thread on the DP forum. Sorry :eek:. Tired of all the mis-info being spread without research. And as puny as mine is it still brings light that there is an issue and is real life "on the street testing which is what makes the results", and I just don't want it to happen to others out there. It SUCKS! Trust me.

At any rate, I've been driving around the city with the camper on (heavy SOB that's as aerodynamic as a freakin barn). It's been in the 90s and oil temps have been steady at 195 to 205*F on the Hwy with A/C. It was at these temps unloaded in the 70s before :eek:. In the city it varies greatly between 185*F (sitting in almost stopped traffic) to 210*F with stop and go with some brisk acceleration from light to light with A/C. The LLY without out the cooler and the (light) camper is steady at 230-245*F under these same conditions with in and out A/C (not using it all the time). Grade pulling in these conditions now, I'm sure would be worse. I am time constrained on testing at this point. The best of the heat is still around the corner and I'm sure there will be interesting findings being reported.
 

malibu795

misspeelleerr
Apr 28, 2007
8,225
542
113
42
in the buckeye state
interesting post.. i saw high oil temps using a IR gun and shooting the oil filter surfuce temps.. right before i lost my block in 07.

just got done swaping this truck over to dmax/4l80 from a 6.5. i gross out at 26,000lb i will probably put the cooler behind the cab layinng flat to allow for natural circulation with a fan to pull it through on a temp switch. and take advantage of all the air natually circulating between the cab and trailer.
549279_3432629488060_568177840_n.jpg
 

chevyburnout1

Fixing it till it breaks
Aug 25, 2008
2,368
1
38
Berthoud, CO
So have a few results to post. Yesterday I made an impulsive trip down to Ramah, CO to buy a jet ski. I get on a long stretch of I-70 where there are no cars at all. Outside temps are about 85°, oil temp is about 220°, coolant is 220°, A/C is on. Ran the truck up to about 100-110mph for about 10-15 minutes with the occasional slow down to 80 when I would need to pass a car. Stock tune, seeing about 24psi boost, 950°EGT's, NO TRAILER, and a pretty nasty headwind. Coolant never moved but oil temp did climb quick. Oil temp ran a consistant 235°. Made a full throttle run up this semi-long hill and temps rose up to 241°. And this was with no load! Once off the interstate the temps did drop back down quickly though.

One thing I did notice though. Anything above 71mph my fan would cycle on and off intermittently. I thought this was odd as going that fast I would think there would be more than enough airflow through the radiator, especially unloaded. My fan has been turning on very easily lately even in relatively cool weather with no A/C. I've pulled two radiators out of customer's truck per their request to clean them. I was amazed at how much junk got washed out of those, and these trucks had 100k less miles on them. So I'm debating on pulling mine out and giving everything a good cleaning.
 

super diesel

<<<< Under Pressure
Interesting Dustin. Thanks for the info. Yea, I took my radiator out last summer (another dang I/C go BOOM) and cleaned it out. Not a lot of debris for 135K and trips all over the US including CAN and MEX. I was surprised. Good info. I'm shocked at what were getting to with EMPTY trucks.
 

chevyburnout1

Fixing it till it breaks
Aug 25, 2008
2,368
1
38
Berthoud, CO
The temps really did catch me off guard, even considering those speeds. And yeah I was talking about cleaning out the external fins of the radiator. My truck has lived a hard life with a lot of miles driving off pavement through mud and brush.
 

super diesel

<<<< Under Pressure
Just did a tuner test today on a short 3 mile hill (about a 4% grade on the fwy) to see how exactly the effects are on oil temps with a little higher power and a 13K GVW load. I've noticed that the oil temps constantly run higher cruising the hwy than in any stop and so or slow speed traffic. First, it was 85*F outside temps. I had the A/C on for both tests. First the stock tune test. The ECTs were 175*F and the EOT was at 181*F and I held the speed limit up the hill and the EOT rose to 190*F and the ECT stayed at 175*F. I returned and then switched to a next tune that is verified at 102+hp over stock and run up the hill. the ECT were at 172*F and the EOTs were at 179*F (lower from running back down the hill). was doing the speed limit up it and then gunned it like I was passing someone. I was doing 80mph at the top and ECTs were at 175*F BUT my EOTs were at 216*F and climbing fast! It took 15 mins of easy driving on flat ground to get it back under 200*F! This just goes to demonstrate what happens when towing on a high HP tune and using some extra hp and what happens to the oil temps. This was a very short hill with a low rise to it at 5750 elv. The heat of ign under cruising and the temps the pistons and the turbo center section shed are far harder than stop and go or slow driving situations. Hope this helps some.
 
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hondarider552

Getting faster
May 28, 2008
10,627
2
36
34
Arizona
I too see higher oil temps with a bigger tune while crusing. Granted it's 105*+ outside here, only cool part of the day is 5-7am :D


I see 195* oil temps cruising in the summer, freeway can get up to 215ish*, but coolant remains sub 200*
 

Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
Well no trailer but I was hauling about 3000-3500# in the bed, 1200# scrap metal, 140 gallons of diesel 980#, 7 large bags 75-80# each, tools jacks etc 400# + 5 people.
I left the race tune in the truck from last year 600ish hp. Truck has the turbos in my sig. Fresh shell rotella 5-40 syn.

Ambient air Temps never got higher than 75*.

What I found was driving normal, semi flat ground (speed limit + 5 mph tops) was that the EOT's would follow ECT. However as soon as I would get on it or pull any sort of a grade I could easily make the EOT surpass the ECT. Max EOT that I saw coming down was 225* pulling some grades in montana maybe a 4-5% here or there nothing like what Michael is testing on in Colorado. That being said I was alarmed at how easily I could raise the EOT with my right foot... Also It takes awhile for the oil to cool back down once it is hot, same thing Michael is seeing...

My lift pump is acting up so my Vegas testing isn't going to happen, taking my parents car down. Which is unfortunate because its supposed to be 105* plus while were there.

I can't imagine what oil temps can get to with a big tune and say 10,000# on back. Scary!

I'm also not convinced that all twins add alot of heat to the oil. My atmosphere charger is a ceramic ball bearing charger, with a .040" oil restrictor. I know for a fact that 60 psi at the engine the big turbo is only getting 25 psi. I just don't see that turbo adding a bunch of heat into the oil, some yes but not huge amounts. Someone with a Journal bearing charger needs to hook the oil temp gauge into the big turbo drain line. Im thinking most of the heat comes from the tune + the load on the truck.

I will be going home through BC which has some monster climbs. I'm curious to see what happens with less load on the truck but bigger hills.

Anywho my oil cooler is going on as soon as I get home.

Thanks guys for opening my eyes!