RAM 1500 Diesel Forum banner

1 - 20 of 23 Posts

·
Registered
Joined
·
17 Posts
Discussion Starter #1
We recently made about a 3,000 mile trip towing our 32', 7,500 lb travel trailer. I love how this thing tows compared to our gas Chevy we traded on it. There's simply no comparison in ease of towing! The one thing I was a bit concerned about was the engine and oil temperatures it reached. On several long, uphill pulls in relatively hot weather (90's) we quite often got a warning that "Oil temperatures high, speed may be limited." I checked and the warning typically came on 265 deg. Once it got to that temp, it seemed to level off, not getting higher than 267 - only once did I see 268. Typically, I tried to keep the engine RPM's to less than 3,000 but was sometimes impossible. The engine temp reached max of about 235. Are these anything to be concerned about? The oil temp on level ground was typically in the mid 240's. I've read threads about possibly altering the grill to allow more airflow and thinking about that, but will that impact the oil temp? Oh, BTW, it does have the GDE tune. Thanks for any suggestions!
 

·
Administrator
Joined
·
2,187 Posts
Fairly typical, my oil doesn't quite get that hot, but I have the honeycomb grill that supposedly flows more air. You don't have to worry, the truck will defuel to keep from hurting itself. The computer is very smart, won't let you destroy the engine if you wanted to.

Just keep in mind that the manual suggests a shorter oil change interval for heavy towing.... sounds like you're there.
 

·
Registered
Joined
·
135 Posts
I just recently towed my camp trailer from Oregon down through the Sierra Nevadas. I saw oil temps over 260 several times on long grades. The highest I saw was 267, but I never saw a high temp warning. I also have a Big Horn so I'm interested to know what the highest oil temp is that someone with a honeycomb grill has seen. I was towing 5000lbs+ with a fully loaded truck at high elevations.
 

·
Super Moderator
Joined
·
3,289 Posts
At least one aftermarket company has a separate oil cooler now available for the ED and I believe two other companies are working on one. Its not as cheap and easy as in the old days in that more computer stuff has to be contended with as its an integrated system. But like John said the truck is smart and it will protect itself by limiting fuel so that the cooling system does not have to work as hard. So if you are content with it you are fine. That is a load of a trailer on a long grade for any 1/2 ton platform.

I have the 3.92 gear which helps and like you the GDE tune, also I use a slightly shorter tire a 275/55/20 ie 31.9" (same as GM & Ford) which cuts the final drive ratio a little more. If you have the 17" wheels they are already only 31.6. The cheapest and easiest improvement may come from a grill swap (edit since you have a bighorn) as the less restrictive grill allows more air flow and at minimum buys more time before a de-fuel situation. Here is a link with some info on that.

http://www.ram1500diesel.com/forum/green-diesel-engineering/6740-coolant-temps-while-towing.html#post88686
 

·
Administrator
Joined
·
2,187 Posts
I just recently towed my camp trailer from Oregon down through the Sierra Nevadas. I saw oil temps over 260 several times on long grades. The highest I saw was 267, but I never saw a high temp warning. I also have a Big Horn so I'm interested to know what the highest oil temp is that someone with a honeycomb grill has seen. I was towing 5000lbs+ with a fully loaded truck at high elevations.
Welcome to the forum! Sorry your truck is upside down... :p

I just got back from a trip towing a travel trailer about 7k lbs. We don't have mountains, but there were some steep short ( 1 mile or less ) and some less steep but long ( 5 mile ) grades and it was very hot. The hottest temps I saw were 256 oil, 238 coolant, and 208 tranny.
 

·
Registered
Joined
·
2,320 Posts

·
Super Moderator
Joined
·
3,289 Posts
ChooChoo great minds think alike. LOL I posted that link above. OP lists a 2015 Bighorn so he has one of the restrictive grills.
 
  • Like
Reactions: choochooman74

·
Registered
Joined
·
17 Posts
Discussion Starter #8
I thank you all very much for the responses. Yes, I do have the restrictive grill. One thing I'm curious about with it though is that there's like a screen behind the grill that seems to me it's restricting more than the grill itself. Why couldn't a person just take that out and keep the rest of the grill?
 

·
Registered
Joined
·
149 Posts
I towed a combined weight of 14,540 lbs truck, payload and trailer from southeast Alabama to central Washington. Total weight given from a truck stop Cat scale. I worked out the trailer to be weighing in at 7,675 lbs, empty truck was 5,800 lbs and truck payload the remaining 1,065 lbs. 855 lbs of the trailer was on the tongue, using the bathroom scale method, so overall gross payload weight on the truck was actually 1,920 lbs. So I guess it's actually a 1-ton capable truck.

On my Laramie with air suspension it drove wonderfully.

I chose to limit my speed to oil temperatures and I chose to keep the oil no higher than 240. That netted me about 65mph on level terrain. On most hill climbs passing through Wyoming, Utah, Idaho and Oregon I usually slowed to 50-55 to maintain my temps. There were two times I let oil temp get to about 255, but I never got any warnings and I re-adjusted speed once I didn't need it. The engineers chose the de-fueling points based on some kind of reference to protect the engine, but being a helicopter pilot I've learned to operate equipment within the limits unless I really need to push it. That's also why they recommend more frequent oil changes.

I know many people on here like to tow with the higher temps and the truck is very capable to do that as you've seen. I also thought it was awesome I was able to maintain about 14 mpg on the 2600+ mile long trip.
 
  • Like
Reactions: Diesel78 and RB33

·
Super Moderator
Joined
·
3,289 Posts
Great report Blackhawk, Keep that up and you may never wear that truck out. :) Is it a 3.92 truck? Because 5th & 55 mph keeps the heat in check and me rolling past semis on the grades. Ram seems to want us to stay at or below 265 oil temp or 240 coolant temp. 65-66 mph is generally the last of really good fuel economy for me pulling an AS on flats or rolling hills. Being a mechanic I presume you have perused the oil analysis thread?
 

·
Registered
Joined
·
145 Posts
I thank you all very much for the responses. Yes, I do have the restrictive grill. One thing I'm curious about with it though is that there's like a screen behind the grill that seems to me it's restricting more than the grill itself. Why couldn't a person just take that out and keep the rest of the grill?

I have a Big Horn as well and tow in the mountains frequently here in Utah during the summer. This past spring I removed the plastics behind the grill....I let the truck do it's thing and I have not seen a heat warning and I have not defueled, I believe I defueled last year once with the plastics in. Not sure that this makes a difference but I believe it does...not necessarily more air to the radiator but it does allow some flow around the motor. My opinion they are there for added fuel Mileage. image.jpeg . Ps- the pic is not mine, but it's the same plastic piece I removed.
 

·
Registered
Joined
·
149 Posts
Great report Blackhawk, Keep that up and you may never wear that truck out. :) Is it a 3.92 truck? Because 5th & 55 mph keeps the heat in check and me rolling past semis on the grades. Ram seems to want us to stay at or below 265 oil temp or 240 coolant temp. 65-66 mph is generally the last of really good fuel economy for me pulling an AS on flats or rolling hills. Being a mechanic I presume you have perused the oil analysis thread?
It's been a while since I thought of it but I'm pretty sure it is the 3.55 gears since I don't tow often. The drive was back in May so the average daily temps were a cool 85 - 75 degrees as I moved from the humid south to the drier northwest. There was a stretch of highway, 300+ miles, through Nebraska that I maintained about 70mph and that's about when I got my worst economy around 13mpg. You can check the Fuelly in my signature for details if anyone wants.

I believe I climbed hills mostly in fifth and after day 2 of 8 I actually chose to NOT use tow/haul mode and just did the manual gear select in hilly areas and mountain climbs. I liked seeing it drop into 8th gear when on level ground.

I have used oil analysis at each oil change and will be doing my 30k in the next weekend or two. Although I don't think I got around to posting the results there.

FWIW my trailer is a 7x16x6'3" enclosed cargo trailer with a 10k lbs rated BlueOx w/d hitch.
 

·
Registered
Joined
·
220 Posts
I believe the GDE tune lowers the oil temp to 265 for warning and derate. The factory tune is higher and that is why some did not get the warning.
 

·
Registered
Joined
·
17 Posts
Discussion Starter #14
I believe the GDE tune lowers the oil temp to 265 for warning and derate. The factory tune is higher and that is why some did not get the warning.
That explains why, when I towed another trailer to Wyoming last October before the GDE tune, I never got the warning. Thank you! I'd been wondering about that.
 

·
Registered
Joined
·
135 Posts
I believe the GDE tune lowers the oil temp to 265 for warning and derate. The factory tune is higher and that is why some did not get the warning.
Anyone know what the warning threshold is for a stock tune? Based on personal experience, it's higher than 267.
 

·
Registered
Joined
·
2,332 Posts
I run 3.55 gears and have never had oil temps over 250. I tow whith the tranny set in 7th with most towing done in 6, or 5th & tow/haul on except in the mountains. When climbing long grades I use 4th gear and the truck lane with flashers on. That has workd good and helps keeps the temps down and gets good mileage.
.I do use cruse control and let the tranny pick the proper gear when not towing in the mountains. Ray
 

·
Registered
Joined
·
135 Posts
I run 3.55 gears and have never had oil temps over 250.
This makes me think the tradesman/outdoorsman grill will be a noticeable upgrade over the big horn. Any grade steep enough to send my truck into 5th gear and long enough to keep me there for a minute or more is going to result in oil temp over 250. I am going to try and switch mine out before the next trailer trip.
 

·
Super Moderator
Joined
·
3,289 Posts
While the grill should be a noticeable improvement based on GDE testing and what they proved on the same grade with the same truck.. Rays temps are more of a reflection of how he tows. A young piss and vinegar behind the wheel who has to lead the charge or maintain his too high of a speed for conditions will find the red lit 265 oil temp on the same grade with the same load. These changes in driving habits change over time as you have to pay for your mistakes.
 
  • Like
Reactions: JohnC and brdurgin

·
Registered
Joined
·
2,332 Posts
Forgot to mention that I removed the motor cover which has helped temp wise also. Also gives me a little more turbo noise.. Will be put it back on this winter.
 

·
Registered
Joined
·
40 Posts
Hi RB....does that motor cover just pop off? I've wondered about removing that to help with heat as it appears to be there for aesthetics? and possibly winter conditions.
 
1 - 20 of 23 Posts
Top