How hot is TOO hot?

[Lyman]

I would agree with running a 5w/30 while doing towing duty. I would think that more heat transfer would be going on between the engine and transmission then you are seeing. 250* is a little high but nowhere near the limit for a quality synthetic. I had a built up Harley that ran 250* all day everyday with no ill effects.

 

[wiswind]

As far as comparison between engine oil temp. and transmission fluid temp, it may be a matter of where the sensor is.
Again, I'm not up on this particular vehicle, but if you are measuring sump temp. on 1 and output temp. on the other.......
The stock temp. sensor for the transmission is used by the computer to adjust shift points relative to the temperature of the transmission fluid.
One thing this does is avoid abrupt shifts in cold weather.
For this reason, maybe they are measuring the fluid at some point at the begining of the flow path.

 

[canadiantim]

Thanks guys. Lots of food for thought. I only use this truck primarily for towing as we have econo-boxes for daily drivers. It sees less that 2000 miles a year so pretty minimal exposure to these high temps.

The few occasions that caused this were short grades that allowed me a cool down period when I hit the top. What concerned me was the rate of temperature rise. It rose like the second hand on a digital watch with no sign of slowing. What if the grade was 5 times longer? Not sure if it would reach an equilibrium or keep climbing even higher.

Trans temp stays very consistent if I keep the OD off. I have seen it touch on upper 190's with a smaller trailer when I tried to run with OD on. Tried a laser on the pan and it is quite close to the gauge readings. As soon as I turn off OD on a grade or headwind, the trans holds temp steady but the engine oil temp climbs with the RPM so is the lesser of two evils. Diff has 3.73's.

I live close to the Rockies so will likely add a cooler and stick with light oils. I'll just pull it off in the fall as I don't like a thermostat in the oil path.

 

[steve20]

for additional reference the Corvette (no oil cooler) has 250 as the middle portion of the oil temp gauge, 300 is the red zone, and 320 is the max on the gauge. In temps above 80, at some point during driving it will hit 228-235, but will settle and run about 212-218 while cruising

The new BMW 3 series I looked at -has the inline 6 turbo, also has 250 as the center mark on the oil temp gauge.

If you continue to run syn, I would start to get concerned at prolonged temps 275 instead of 250

 

[SteveSRT8]

Originally Posted By: Jim Allen
I think if everyone had oil temp gauges, we would all learn a lot and hershey-squirt less. Hot is normal.


I had lunch at Homestead raceway with the senior VP of the SRT division during an SRT Track Experience put on by Skip Barber.

One of the things we discussed was the very high oil temps observed during hot laps using both the infield raceway and half the big oval. Temps frequently got very close to 300 degrees.

He said their extensive durability testing includes LOTS of testing at much higher temps! 300 degrees was not considered too high with M1 0w-40 as factory specified.

I have since seen a bit over 300 at a track day and subsequent analysis showed no degradation at all.

 

[PZR2874]

^After ever hard run(s) on a track day, I've always changed my oil. Be it will 500 miles on it or 2500.

For sanity purposes

 

[SteveSRT8]

Likewise, I didn't mean to imply I ran the oil for a full interval or anything.

BTW, I've been to road course track days with Amsoil Dominator as well in both 30w and 50w and they held up perfectly as well at 300 plus degrees.

 

[PZR2874]

^Agreed

 

[Jim Allen]

Originally Posted By: canadiantim
Thanks guys. Lots of food for thought. I only use this truck primarily for towing as we have econo-boxes for daily drivers. It sees less that 2000 miles a year so pretty minimal exposure to these high temps.

The few occasions that caused this were short grades that allowed me a cool down period when I hit the top. What concerned me was the rate of temperature rise. It rose like the second hand on a digital watch with no sign of slowing. What if the grade was 5 times longer? Not sure if it would reach an equilibrium or keep climbing even higher.

Trans temp stays very consistent if I keep the OD off. I have seen it touch on upper 190's with a smaller trailer when I tried to run with OD on. Tried a laser on the pan and it is quite close to the gauge readings. As soon as I turn off OD on a grade or headwind, the trans holds temp steady but the engine oil temp climbs with the RPM so is the lesser of two evils. Diff has 3.73's.

I live close to the Rockies so will likely add a cooler and stick with light oils. I'll just pull it off in the fall as I don't like a thermostat in the oil path.



Interesting observations, thanks. Used to live in the Colorado Rockies myself but I didn't have my current F150 there. I have no experience with this truck in those conditions. I wonder what the 10 percent of gearing difference between your truck and mine (3.73 to 4.10:1) would amount to in EOT and TOT. Sounds like you are going to do the cooler. If so, please keep us informed as to details. There are a few other F150 folks here that would appreciate the info.

You said you truck has the tow package. Does that include the 9-row auxiliary cooler? If so, that, and your obviously well-honed piloting skills, account for keeping the trans cool. During harvest I regularly tow VERY heavy loads with my truck (loaded grain wagons) and the trans stays amazingly cool. But again, this is fairly flat ground and grades make a big difference.

 

[BISCUT]

Just to throw out some info...04 F-150 5.4 3V with 72k miles. Mine has tow package which included 3.73 gearing and an oil cooler as well as trans cooler.

I also run an Edge Evo and ambient 70F with no towing (650lb quad in bed) my oil temp is reading 205 range after heavy load up some hills. My transmission temps have been 145-155 range in 40F to 70F.

Not sure if this helps you much, but at least apple to apple vehicle wise. I would think your transmission would be running a bit hotter under those loads.

I am running MC 5-20 MC 820S filter and recently changed my transmission filter and fluid with Mercon V.

 

[Jeff_in_VABch]

Originally Posted By: steve20
for additional reference the Corvette (no oil cooler) has 250 as the middle portion of the oil temp gauge, 300 is the red zone, and 320 is the max on the gauge. In temps above 80, at some point during driving it will hit 228-235, but will settle and run about 212-218 while cruising

The new BMW 3 series I looked at -has the inline 6 turbo, also has 250 as the center mark on the oil temp gauge.

If you continue to run syn, I would start to get concerned at prolonged temps 275 instead of 250


Almost all late model vehicles feed the gauges off the CANbus and the gauges are not actually connected to any sending unit. What you get is very marginal information, essentially what the PCM wants you to see.

250F oil temp is incredibly high.

 

[Jeff_in_VABch]

Originally Posted By: Jim Allen

This approach is valid if he's running around 80 percent of the time at 220 to 250F. If his truck spends 5 percent of its time towing, and only 20 percent of that time at those temps, that's not very much time! Addressing a situation that's less than one percent of the total operating time is a silly waste of money. Plus, if he installs some monster cooler he may overcool the oil schlepping around in the Canadian chill and creating sludge.... unless he installs an oil thermostat which really adds to the cost. Again to address high oil temps that last only minutes. You spend 10-15 minutes going up a hill, the oil gets hot and then it cools down again. No harm, no foul. It's time at temp that kills oil and engine parts.


That 1% of the time is when most of your engine damage and wear is going to occur.

Heat soak related engine damage may not cause an immediate failure, but almost everything is wearing at an extremely accerated rate at high temperature. I.E. - the valve springs use oil flowing over them for cooling, as they cycle faster (high RPM), they create more friction related heat. Even if the spring does not fail (and they do), it will lose considerably more temper at elevated oil temperatures.

Also, almost all pancake adapters have a thermostatic valve built into them, always have. If not, they are also available at a reasonable cost.

 

[lui]

i have run my engine oil up to 290-300f at the race track for a few laps with no issues....it constantly sees 220-230f if i'm cruising on the highway for any extended periods of time. it normally runs around 190-210f.

 

[salgra]

Don't be affraid! keep using 5w20 it really has no problem at all. I would be confident to run the motor hard to about 300F , higher temp?, throttle back a little. above 330F? consider letting it cool a bit.

 

[Jim Allen]

Don't you think you are "chicken-littling" things just a little bit?

1) Who said anything about high rpms? He's towing... 3K-3.5K rpm at best.

2) Also, don't you think these thing were all accounted for when the engine and oil were designed? The oil gets hot. It cools off again. 250F short term isn't a big deal. If it was, the cars in Phoenix would be dropping like flies.

3) And it takes a lot of heat to take the temper out of a valve spring. The materials I have at hand says it takes 400F+ for an ordinary steel spring and many are better than that. Granted, spring temperature can be a problem with race engines turning at high rpm. I have seen valve springs smoking on dyno engines that had spent a bunch of time at high rpm, though the one time I thought to investigate it, a heat gun only showed about 360F. This was an engine making multiple runs to 8K+ and making 700 hp or so. From that, I could agree that a race engine running long periods at a high output could generate enough heat to hurt a set of passenger car valve springs.

4) To say "almost all" sandwich adapters have t-stats built in is a bit of a stretch because I went looking for one for my 5.4L recently and most of what I found was not t-statingly controlled, though you can find plenty that are if you need one.

5) Finally, with a t-stat in place, I don't see any harm in running an oil cooler but, obviously, I don't see the need either. It's entirely up to the vehicle owner how to spend his money. I KNOW it would be a waste for my truck and if I was in the OP's position, I would also consider it a waste.

 

[RWDIII]

Thank you guys at BITOG for this discussion.
I have a 2006 5.4 with tow package and As I tow and live in the Ariz desert,have been concerned with the MC 5-20 that is used in the F150.I would like to ask a few questions.
My F150 has no oil cooler,but has trans cooler.
My F150 takes 7 qt oil.
I searched the Ford site and they do not use oil cooler on
F150 or F250 gas engine
So how do some say they have an oil cooler?
I assume the oil coolers and oil guages aftermarket
Thanx

 

[canadiantim]

From what I've seen, the pre-2004 5.4 2 valve engines had an oil cooler available. I've seen (poor) photos and it's a strange shaped piece that is mounted between the block and filter. The block side has a triangular mount so it's not just a bolt on item that relocates the filter lower. It's tied in to the coolant for cooling.
I have not seen anything factory on the internet for the 2004 up 3 valve motors though.
I do plan on getting to the dealer to see what, if anything they have. There must be something available as the same 5.4 motor is available in the F350, which could be up to 2000lbs heavier so would make the engine work that much harder.

RWDIII, I'm going to be in Arizona in a few weeks. Hoping to buy some "accessories" while enroute there since everything south of the border is so much cheaper than up here.

 

[RWDIII]

From what I've seen, the pre-2004 5.4 2 valve engines had an oil cooler available. I've seen (poor) photos and it's a strange shaped piece that is mounted between the block and filter. The block side has a triangular mount so it's not just a bolt on item that relocates the filter lower. It's tied in to the coolant for cooling.
I have not seen anything factory on the internet for the 2004 up 3 valve motors though.
I do plan on getting to the dealer to see what, if anything they have. There must be something available as the same 5.4 motor is available in the F350, which could be up to 2000lbs heavier so would make the engine work that much harder.

RWDIII, I'm going to be in Arizona in a few weeks. Hoping to buy some "accessories" while enroute there since everything south of the border is so much cheaper than up here.
[
you will be welcome in Arizona/quote]Thanks for the comeback.p

 

[Jim Allen]

Yes all the oil cooler stuff we've been talking about is aftermarket sourced. Oil temp can be read via a programmer or scangauge via the OBDII port. AFAIK, the 3-valves did not have an oil cooler in any light truck application. I would look to V10 medium truck applications for the possibility of an oil cooler but if you really want one, there are good sandwich adapters with t-stats as Jeff in VB mentioned and the aftermarket stacked coolers are usually pretty good. And easy to source. I guess I said my piece about whether you need a cooler or not ( : < ).