Higher engine oil temps and 4th gear tow/haul

[Wade512]

So kind if a 2 part question here. Took a trip over the 4th, and while in tow/haul mode truck wouldnt shift out of 4th gear(had it manually selected to 6th). I was running about 67 mph and it was about 80 degrees outside, also normal highway landscape in minnesota, no steep grades and the such. Is it normal for it not to shift from 4th even if 5th is selected?

Second part is while driving same time i noticed oil temps reaching mid 240’s and dropping to high 230’s. I was pulling the camper and with everything loaded down was between 6500-7000 at very most, and was about a 5 hr trip. The engine coolant run perfectly normal, get to about 208-210 then drops everytime. Is the oil temp running that high pretty bad or more normal for these trucks with the 6 speed, or is there a cause for concern here?

Truck is a 2016 2500 laramie with 6.4, 6speed and 3.73 gears and 35” tires.
Thanks in advance

 

[SniperDroid]

What were your RPM's running? I have the 8 speed transmission in my 2019, never saw oil temps that high except when I had a Ford Diesel. My oil temp usually runs about 10 to 15 degrees higher than coolant. Tranny temp about 160 to 170. Towing the same type load here in Ohio.

 

[Toddz]

So kind if a 2 part question here. Took a trip over the 4th, and while in tow/haul mode truck wouldnt shift out of 4th gear(had it manually selected to 6th). I was running about 67 mph and it was about 80 degrees outside, also normal highway landscape in minnesota, no steep grades and the such. Is it normal for it not to shift from 4th even if 5th is selected?

Second part is while driving same time i noticed oil temps reaching mid 240’s and dropping to high 230’s. I was pulling the camper and with everything loaded down was between 6500-7000 at very most, and was about a 5 hr trip. The engine coolant run perfectly normal, get to about 208-210 then drops everytime. Is the oil temp running that high pretty bad or more normal for these trucks with the 6 speed, or is there a cause for concern here?

Truck is a 2016 2500 laramie with 6.4, 6speed and 3.73 gears and 35” tires.
Thanks in advance

The oil temps are consistent with mine especially if towing in wind or on grades. As for the gears, by putting on 35s, your effective rear end ratio is a 3.55 rear end. That will negative impact your truck on holding a higher gear towing.

 

[Wade512]

What were your RPM's running? I have the 8 speed transmission in my 2019, never saw oil temps that high except when I had a Ford Diesel. My oil temp usually runs about 10 to 15 degrees higher than coolant. Tranny temp about 160 to 170. Towing the same type load here in Ohio.

I cant quite remember exactly but ide say 2400-2700, and tranny temp held steady at 167-169, maybe a bump to 170 but then right back down

 

[Wade512]

The oil temps are consistent with mine especially if towing in wind or on grades. As for the gears, by putting on 35s, your effective rear end ratio is a 3.55 rear end. That will negative impact your truck on holding a higher gear towing.

Ok, yeah the bigger tires did have a noticable impact, went out to yellowstone last summer and held crusing speed of 70-75 and no problems with no higher than normal temps at all on stock size tires. Next on the agenda is a bigger camper(bumper pull again) but gunna be looking at 4:10 or 4:55 gears

 

[Daw14]

I’m in south Florida where it’s always hot , your temps are normal for pulling something. I did 4.56 and could not be more satisfied.

 

[Toddz]

Ok, yeah the bigger tires did have a noticable impact, went out to yellowstone last summer and held crusing speed of 70-75 and no problems with no higher than normal temps at all on stock size tires. Next on the agenda is a bigger camper(bumper pull again) but gunna be looking at 4:10 or 4:55 gears

I have 4.11 gears and stock tires on my 2018 2500 4x4. I tow a toy hauler between 7600 and 9800 lbs depending on what toys I take along. It tows great. If I were towing any more weight, I would probably go at least 4.56 and with 35's would seriously consider 4.88.

 

[buckeyexx]

Your truck is the same as mine other than mine being a 2015 and I have stock size tires. I do run Toyo open country at3 so a little more rolling resistance on them than a regular highway tire.
As far as not shifting out of 4th gear I would say that is normal especially with 35’s. When I had my travel trailer I would actually put my truck in 4th gear and it felt much better than going into overdrive 5th gear. The rpms would run around 3k but the fuel mileage would actually be a little better since it wouldn’t be gear hunting. These trucks like to run a little hot when working them so I think your oil temp is ok. As long as your running a good quality synthetic oil you will be fine.
One thing I would suggest if you tow a lot is to put a transmission thermal bypass block on it. It will keep your transmission about 20-30 degrees cooler. If it fails it will cook your trans quick.

 

[buckeyexx]

Also if your in tow/haul your truck will never go into 6th gear. It will go into the first overdrive gear which is 5th gear but not the second which is 6th.

 

[nascar72]

I have a 2500 3rd gen with the 5.7 and 3.73 gears, 5 spd auto. with oem tire size Lt265/70/17 and while towing my roughly 7500lbs 5ft wheel camper trailer, I don't even bother with tow/haul mode and go straight to locking out both overdrives and drive it in 3rd gear since I encounter many steep grades. At 55-60 mph, I'm cranking around 2500-2800 rpms. Never had any issues as for either trans and water temps.

 

[Wild one]

So kind if a 2 part question here. Took a trip over the 4th, and while in tow/haul mode truck wouldnt shift out of 4th gear(had it manually selected to 6th). I was running about 67 mph and it was about 80 degrees outside, also normal highway landscape in minnesota, no steep grades and the such. Is it normal for it not to shift from 4th even if 5th is selected?

Second part is while driving same time i noticed oil temps reaching mid 240’s and dropping to high 230’s. I was pulling the camper and with everything loaded down was between 6500-7000 at very most, and was about a 5 hr trip. The engine coolant run perfectly normal, get to about 208-210 then drops everytime. Is the oil temp running that high pretty bad or more normal for these trucks with the 6 speed, or is there a cause for concern here?

Truck is a 2016 2500 laramie with 6.4, 6speed and 3.73 gears and 35” tires.
Thanks in advance

The 6.4's have piston oil squirters,so they usually run noticably higher oil temps then the 5.7's do.The harder you work the engine,the hotter the pistons run,consequently the oil will run hotter,because the squirters are spraying oil on the bottom of the pistons,to keep the piston temps in check.

 

[Toddz]

The 6.4's have piston oil squirters,so they usually run noticably higher oil temps then the 5.7's do.The harder you work the engine,the hotter the pistons run,consequently the oil will run hotter,because the squirters are spraying oil on the bottom of the pistons,to keep the piston temps in check.

That is good information to know. I did a lot of research on what normal oil temps were when I first started towing with the 6.4. I never got an actual answer, but it appeared the oil runs hotter so I just accepted it because it does a really good job even with the 6 speed towing.