Engine Temp how hot is too hot?

[k9jadon]

So I was just wondering what any of you guys think about this? A few years ago I went camping in the Eastern Sierra Nevada. A place called Tuff Campground. I drove an all stock other than a 4in turbo back exhaust '05 F-250 6.0 dsl and pulled an approx. 10k lb fifth wheel. My question is this, When climbing a grade that is approx. 6% for about 8 miles with ambient air temp hovering around 100*f how far would you want or allow your temp gauge to go b4 pulling off and allowing it to cool off? 1/2, 2/3 , 3/4 or until the light comes on? I kept the boost pressure at or near 20 psi and this formula translated to climbing the grade around 32-35 mph, I think it was running around 3000 rpm or so, and the temp gauge remained for the entire climb at its normal position, it never moved, could I have pushed the truck harder? Is the cooling system designed to run for long periods say like 15 minutes or so at the 2/3 mark or higher on the gauge? I am sorry I do not have actual water temp numbers since my gauge is stock, so I have to give points of reference on the gauge as a description. Any thoughts will be appreciated. BTW I am not looking to drag race up the hill, I just want to know if my truck can handle more?

[time2roll]

No, mine moves fine and steady when it moves.

Kinda like this only for coolant: http://www.intellidog.com/dieselmann/b_smoke13.htm

[Sport45]

smkettner wrote:
Skip the gauge as you already have one. No worry until the needle actually moves.
My Ford does the same. In 14 years I have seen the needle move just a nudge 3 times.
Plenty o' time to adjust speed if needed. I just held the hammer down.

BTW 50/50 coolant and 15 psi is good to 265F.

Your 2001 Ford probably has the same temperature gauge my 2000 F250 did. It does not really respond to coolant temperature. It will indicate "normal" until some temperature limit is reached and then it will immediately peg to "hot". The gauge indication does not climb as the coolant gets hotter.

Hence the moniker "idiot gauge". It indicates okay or too hot with nothing inbetween.

The oil pressure gauge in our 2005 Envoy is similar. There is no pressure sending unit, only a switch. If the oil pressure is above something like 7 psi the gauge will indicate what the computer thinks the pressure should be based on rpm and maybe temperature. If the actual pressure drops below the ~7 psi setpoint the gauge drops to 0 and the check engine light comes on.

I hate idiot gauges, but understand their need from the automakers perspective. The general public likes to see gauges but don't understand that it's okay for the needles to move.

[time2roll]

Skip the gauge as you already have one. No worry until the needle actually moves.
My Ford does the same. In 14 years I have seen the needle move just a nudge 3 times.
Plenty o' time to adjust speed if needed. I just held the hammer down.

BTW 50/50 coolant and 15 psi is good to 265F.

[face_down]

mkirsch wrote:
Everybody keeps saying how the gauges are no better than idiot lights...

If they're functioning properly, they will tell you when it's too hot, even if they're just "idiot gauges."

Unless you go old school with mechanical gauges, you're still depending on the computer and electronic sensors to tell you what the definition of is is. What's saying the sensor is not an idiot sensor too?

That's because they (everybody) knows what they are talking about. They are called idiot gauges for a reason, by the time they are in the red it can be potentially too late and major damage has already been done. A PID monitor like the Edge Insight will alert you to a potential problem before you have a problem AND way before an idiot gauge will even move. You can set an alarm for just about anything (both visual and sound)....which I do for coolant, oil, tranny and EGT temps along with boost and voltage (battery and FICM) This type of setup gives you real time and actual numbers to monitor.

As for 6.0's the thermostat does not fully open until you hit 219* and that is when your electric fan will come on...and you can not miss it as it sounds like a helicopter taking off. If I remember correctly temps of 235* are when you start getting in trouble, I have my alarm set at 220* (and have never hit it). More important is you want to make sure the delta between your coolant and oil temps do not have a sustained difference of 15*, if so, that is when you are having an oil cooler failure and if you still have a EGR cooler in the truck all hell can break loose. Finally EGT's pre-turbo should not exceed 1300*.

[larry_barnhart]

My friend had an 06 F360 srw 4x4 and towed a 38 ft fifthwheel. He told me several times he towed the highway though the Eisenhower tunnel highway and his truck didn't even slow down. OK wow that is great I said but no way from what others have told me.

chevman

[roadnerd]

ib516 wrote:
FYI, the engine temp gauge on my 2007 Ram/Cummins was "damped".

It would rise as the engine temp rose, then stop at about the 2/3 - 3/4 mark, even as engine temps continued to rise (as per Scangauge2). Then, after the engine temp reached a certain point (I forget what it was, it would be in Celsius anyway), it would shoot up a 1/4" in 2 seconds, then read linearly again, as it did for the bottom half of the temp range.

I noticed this happen several times when towing up maountain grades in Utah at 100*F outside temps. I eventually backed the power adder (programmer) down a bit to reduce engine temps.:C

"nonlinear gauges' 😉

Just like most analog fuel gauges (6.0 Ford included) - 100 miles to get to 3/4 tank, another 75 to to to 1/2, with 1/4 being much closer to empty than 29 gallons / 4.

[ib516]

FYI, the engine temp gauge on my 2007 Ram/Cummins was "damped".

It would rise as the engine temp rose, then stop at about the 2/3 - 3/4 mark, even as engine temps continued to rise (as per Scangauge2). Then, after the engine temp reached a certain point (I forget what it was, it would be in Celsius anyway), it would shoot up a 1/4" in 2 seconds, then read linearly again, as it did for the bottom half of the temp range.

I noticed this happen several times when towing up maountain grades in Utah at 100*F outside temps. I eventually backed the power adder (programmer) down a bit to reduce engine temps.:C

[Tystevens]

mkirsch wrote:
Everybody keeps saying how the gauges are no better than idiot lights...

If they're functioning properly, they will tell you when it's too hot, even if they're just "idiot gauges."

Unless you go old school with mechanical gauges, you're still depending on the computer and electronic sensors to tell you what the definition of is is. What's saying the sensor is not an idiot sensor too?

Yep. The 'idiot' gauge' tells you what the engineers want you to know. It is too hot or it is not too hot! Honestly, that is sufficient for me. Some people try to out-think the engineers or address things that aren't really a problem.

And the reason to have custom gauges on the 6.0 is to measure the oil and coolant temps ... if one becomes significantly hotter than the other, you have a blockage that is going to cause a lot of problems if not remedied. The EGTs aren't a problem on a stock 6.0 (or any other stock diesel, for that matter) -- only a potential problem when you're chipped.

[roadnerd]

mkirsch wrote:
Everybody keeps saying how the gauges are no better than idiot lights...

If they're functioning properly, they will tell you when it's too hot, even if they're just "idiot gauges."

Unless you go old school with mechanical gauges, you're still depending on the computer and electronic sensors to tell you what the definition of is is. What's saying the sensor is not an idiot sensor too?

Idiots lights are binary (on/off). Monitors are continuous and allow you to see several different parameters at the the same time (and also sometimes require interpretation). I'll take monitors over idiot lights any day, I'd rather know the big picture. Mechanical gauges (and the probes/sensors that feed them) are subject to failure as well. I'd also take mechanical gauges (like the gauge I run for EGT) over an idiot light any day.

[mkirsch]

Everybody keeps saying how the gauges are no better than idiot lights...

If they're functioning properly, they will tell you when it's too hot, even if they're just "idiot gauges."

Unless you go old school with mechanical gauges, you're still depending on the computer and electronic sensors to tell you what the definition of is is. What's saying the sensor is not an idiot sensor too?

[transamz9]

OP, if you are truly stock like you say and your 6.0 is in good mechanical condition,put your foot in it and let it run. That's what it likes to do. Mine sees 3,500+ RPM on a regular basis and I will run 20# of boost on flat ground a lot of times. The F550 that we have pulls heavy every time it goes out. I'm talking loads where the whole rig is grossing 35,000# and over. When it is that heavy running down the interstate your foot is on the floor 80% of the time just to hold speed. Like I said before, if your 6.0 is in good mechanical condition let'er run. She likes it.

[roadnerd]

mabynack wrote:

carringb wrote:
Having a 6.0 PSD means you really need a ScanGauge, UltraGauge or similar digital gauge monitor. Knowing not just specific coolant temps, but also oil temps and other parameters is essentially to not having a total engine meltdown on the side of the road.

I would not except 10,000 pounds up a 6% grade to even move the needle! This alone makes me worried your truck may not be cooling properly. Have you pulled a coolant sample lately to make sure there's no "tapioca" or other contaminates in the system? Tapioca-like precipitates are the first sign your coolant is breaking down (or is reacting because non-compatible coolant was added) and this can quickly plug the engine oil cooler, which will cause the EGR cooler to blow.

FWIW - the hottest I've seen on my V10 was 223F. That was climbing Death Valley west-bound, which I think is a 12% grade? Whatever it is, its steep and long, and it was 107F the last time I pulled it, with 15,000 pounds in tow. The 6.0 does seem to run a little warmer normally though.

x2

I put a scan gage on my 6.0 after I blew a head gasket and the temperature gage pegged. I had the heads rebuilt, the EGR and engine oil cooler replaced.

If everything is mechanically sound and the coolant isn't contaminated, I would slow down or pull off the road if my temperatures got over 220. I found that just slowing down a bit when climbing a hill can reduce coolant temperatures by 10 degrees.

Slowing down REALLY does make a difference, doesn't it? This is my 1st diesel, and I had to re-learn how to tow/drive to some extent. Diesels seem to be much more "fuel in -> heat out". Tow/haul and downshifting (with right hand, not right foot), also helps to cool it down in my experience - since the oil is the primary heat transfer medium, moving more of it into the oil cooler does work. There is nothing wrong with pulling over to cool down a bit either - all of this is facilitated by precise monitoring of course....

[mabynack]

carringb wrote:
Having a 6.0 PSD means you really need a ScanGauge, UltraGauge or similar digital gauge monitor. Knowing not just specific coolant temps, but also oil temps and other parameters is essentially to not having a total engine meltdown on the side of the road.

I would not except 10,000 pounds up a 6% grade to even move the needle! This alone makes me worried your truck may not be cooling properly. Have you pulled a coolant sample lately to make sure there's no "tapioca" or other contaminates in the system? Tapioca-like precipitates are the first sign your coolant is breaking down (or is reacting because non-compatible coolant was added) and this can quickly plug the engine oil cooler, which will cause the EGR cooler to blow.

FWIW - the hottest I've seen on my V10 was 223F. That was climbing Death Valley west-bound, which I think is a 12% grade? Whatever it is, its steep and long, and it was 107F the last time I pulled it, with 15,000 pounds in tow. The 6.0 does seem to run a little warmer normally though.

x2

I put a scan gage on my 6.0 after I blew a head gasket and the temperature gage pegged. I had the heads rebuilt, the EGR and engine oil cooler replaced. I really wouldn't rely on the factory gage. I've seen my scan gage get up to 217 degrees and my factory temperature gage was barely above the middle of the gage.

If everything is mechanically sound and the coolant isn't contaminated, I would slow down or pull off the road if my temperatures got over 220. I found that just slowing down a bit when climbing a hill can reduce coolant temperatures by 10 degrees.

[roadnerd]

k9jadon wrote:
Roadnerd,


That is where I saw the grade I was speaking of, It was Sherwin Grade on the 395 just north of Bishop. I wasn't overly worried I just wondered if I was babying it to much. My temp gauge (stock) didn't move at all so I figured I was doing alright. I will look into getting a scangauge or some other type of meter in order to properly monitor the temps. Thanks again for all the replies.

The general consensus is that the stock gauges are worthless, and don't really correlate to what the temp actually is. Enjoy your new monitor, knowledge is power.