Need help again - transmission overheating while towing

[Loppy Crimp]

I have a similar setup, 2016 2500 Outdoorsman. Just bought it used with 175,000 miles. I tow a 10,000 5th wheel with no problems. Just went to Lake Tahoe (up to 8500 ft from sea level) with no issues at all. Highest RPM hit was about 2800-3000 and that was while climbing hill at 55 MPH. Temp rose a bit, but very little. Outside temperature was about 75-80 deg.
Since I refuse to take my truck to anyone, except as a last resort, I would try the basics first.
Drain and fill your transmission fluid with new and change that thermostat. Be sure to pull the pan after draining to look for any signs of metal (copper) shavings. Set aside half a day and do this. REALLY cheap insurance.
Might also want to change the differential fluid in the gearboxes as well.
These trucks should pull up to 17,000 lbs without issue.

 

[Loppy Crimp]

I guess I forgot to ask. Is it a Diesel or Hemi? I opted for the Diesel. This Beast will tow anything!!!!

 

[Socal_greywhale]

Months ago I joined here to ask about fifth wheel weight and our truck's capabilities. I got a lot of great info and advice. We finally made a decision and purchased a fifth wheel in January. Took it on its maiden voyage Easter weekend. Everything went great. We took it on its second trip this weekend and on the way home, the check engine light came on, then shortly after a message showed up saying "transmission is too hot". So we had to pull over for a bit. One thing to note, we had it in 'tow/haul' mode. Whenever we started going after a red light, the transmission would make a very hard shift at 2500 RPMs. That stopped after the truck cooled down. We made it home safely, but the check engine light was still on.

We have a 2015 2500 Tradesman with the 6.4 hemi. We do have an appointment next week to have it looked at, but wondering if anyone has experience with this issue? Any ideas on what would cause it? We plan on taking it on a long trip next month and I'm concerned.

I feel for ya on the tranny issues, its heartbreaking. I had the same issues, my 2015 Hemi tranny failed 3x (while on travel towing a TT), luckily all covered by extended warranty and AAA for the tow. My solution after the 2nd time was to change out the trans Fluid Bypass Solenoid to the ATS equivalent. Solved the issue for overheating, but the 3rd time was in summer and the torque converter just failed climbing up a grade. So after the 3rd time I re-geared from 3.73 to 4.56. Been pulling strong since then and no issue with tranny temps. Hope this helps.

 

[RD Holland]

Different truck but still a Ram ... I had very little time once the transmission "hot" warning came on. Was only about a week or less before the whole trainy had to be rebuilt. First thing I saw was it getting stuck in "overdrive". Then it got "hot". I took it in when the overdrive issue showed up and was told there was no issue. They tweaked something and cleared out the codes. A few days later I was sitting on the road to let it cool. Made a call and was told "We know what's wrong. Bring it in Monday and we'll add a transmission cooler to the truck." I hung up and never called back - it was a 2001 2500 with trailer hauling package and it has a huge transmission cooler on it. Had to have a friend come hook up to my boat and pull it home. Barely got the truck to a real transmission shop. In fact, it completely burned out just as I pulled into their drive. But, mine was ten+ years old then and had nearly 80k miles on it.

 

[Gary Fields]

For the weight of your trailer I believe your truck is marginal to tow. There are a few things to try to help it out. First, make sure your trailer is as light as possible. Eliminate any extra contents- pack light. Make sure you carry a minimum of water in the tanks. My ex-father in law once drove a motor home from Pennsylvania to the Black hills with a full 100 gallon tank. That's 820 pounds. I think he could have got by with 20 gallons. Second, go back to stock tires and rims. Bigger tires raise the effective gear ratio. With 3.73 gears a little help from the tires will help. With lower tires you may want to remove the spacers and any lift. My son did this to a truck he brought and found it made it much better driver and less air resistance. Third, add an aftermarket transmission cooler. I've put coolers on all kinds of vehicles since the 80's. Generally you can't cool transmission fluid too much, except maybe a Canadian winter. A bigger cooler dissipate more heat. Get the largest one that will fit. You can also get remote spill on filters for the tranny. I think these will help your towing.

 

[MAC830203]

Your torque converter is slipping. Worked great, then.... getting too hot. Change filter to old type yellow filter. Has Better flow. Get the best converter that is for towing. Hughes is great. But local shops sometimes make great converters. FL torque Converter makes a custom disk. Get a 165* thermostat and a fan controlled trans cooler. Probably 6-750$. Or.....your clutches are crap and need a rebuild. Lastly, that slam you hear in tow mode makes me think your trans has been rebuilt and doesn’t have the OD waved snap ring. 3.73 are fine for your rig but yes, taller gears help. 4.5’s are good with 36” tall tires. The fifth wheel is great. So much better than a hitch. Great investment. You have a great truck for the trailer. My concern is that you have a rebuilt transmission and a shop that hasn’t a clue that rebuilt it. I could go on. Check if it’s been rebuilt. I have a 96 1500 408 / 46Re 2wd that will pull a 30’ boat up a small incline @ 900rpm. And never gets above 180*.

 

[MAC830203]

If you’re down here in SC, I’ll rebuild it for $0. You buy parts. But need 2 weeks for parts.....

 

[15Ram64]

I guess I forgot to ask. Is it a Diesel or Hemi? I opted for the Diesel. This Beast will tow anything!!!!

It’s the 6.4 hemi.

 

[Bldrinker]

Here is my trailer. This trip it’s loaded heavy around 13k. Truck is a 6.4 with 34” tires and 4:88 gears. Up Sherwin pass in Bishop trans never got over 180.

truck tows with ease, except the fuel mileage 5.7mpg

 

[GsRAM]

The tow rating of the OPs rig is same as mine. 12,600 I believe is the limit with 3.73s and the 6.4. With 4.10 gears its 15,600, the 4.10s get you 3k more tow rating.

With the OPs oversize tires she has less than 12,600, probably closer to 11,000, just a guess, but those bigger tires reduce the overall limit and they are heavier I am sure.

OP, know that your at the upper limit with that large 5th wheel. As suggested by others, I concur, remove the leveling/lift kit. Go back to stock suspension, put the factory tire and wheel combo on it and pack as light as possible. Run with your fresh, gray and black tanks dry or close to it.

This is after you get resolved your current issue. You said the first trip out it did great. It may have, but it may have been working harder than you realized, or as said by another poster, towing is hard on equipment and your weak points will show quickly. Good luck, hope all works out for you

 

[ripping r]

The tow rating of the OPs rig is same as mine. 12,600 I believe is the limit with 3.73s and the 6.4. With 4.10 gears its 15,600, the 4.10s get you 3k more tow rating.

With the OPs oversize tires she has less than 12,600, probably closer to 11,000, just a guess, but those bigger tires reduce the overall limit and they are heavier I am sure.

OP, know that your at the upper limit with that large 5th wheel. As suggested by others, I concur, remove the leveling/lift kit. Go back to stock suspension, put the factory tire and wheel combo on it and pack as light as possible. Run with your fresh, gray and black tanks dry or close to it.

This is after you get resolved your current issue. You said the first trip out it did great. It may have, but it may have been working harder than you realized, or as said by another poster, towing is hard on equipment and your weak points will show quickly. Good luck, hope all works out for you

why remove remove the leveling kit. lots of use have them. and dont have problems

 

[GsRAM]

Trucks in general and HD trucks well, have a factory rake for a reason, so when you load them heavy, you don't have headlights pointed at the sky and to keep weight on the front axle for steering and braking performance. They naturally level out unless very heavily loaded. They look cool though, but are not for me personally.

You can compensate for that with airbags, but in general, when towing heavy, I don't think they are a good idea. But YMMV

 

[17Dually]

This has been covered pretty well. The big tires and the gears will definitely work your engine and transmission harder which makes more heat. Driving in 4th or 5th and reducing speed will help that once you get going. However getting started and or some stop and go traffic will heat things up quickly. A plugged bypass will also result in an overheated transmission. One easy and cheap thing to do would to make sure the airflow through your radiator and transmission & other cooler fins etc are not restricted (bugs or?). Another thought, it was mentioned that turning off the AC will make the overall engine temps cooler, one other way of removing heat is turning on the heater ~ although I suspect either of those would have a marginal effect on transmission heat.
Good luck

 

[zippertom]

Go back to stock tire size. I have the same Tradesman truck and 6.4, 3.73 gear and tow Montana HC 325RL at 12,700 lbs with no issues through the Smokey Mountains with no problems.

In the mountains I keep the tow/haul mode on. Transmission and engine temps run normal.

 

[zippertom]

Let me add that my tires are Michlin LTX LT 275-70R-18. I run the highway at 65 mph max, get 9 to 11 mpg, use regular 87 gas. I use Lucas fuel treatment every 3rd fill for added top cylinder lube and run stock 0-40w oil.

 

[FlyingRAM]

You must first rule out any mechanical issues as mentioned.
Second, You’re running oversized tires on higher gears, which only makes it worse. Go back to stock sized tires or change gears.
Third, consider installing a larger transmission cooler. I added a 6x10inch stacked plate cooler in my 2012 for $40 and a Saturday morning.
4th-service the tranny fluid regularly. I don’t know your service history but if that’s the original fluid on a used truck that’s hauling heavy loads then it’s probably done. I installed an aftermarket pan with a drain plug that makes Servicing much easier. They’re also increase capacity pans that carry a quarter to more fluid. I’ve also heard that Red Line ATF is an improvement over factory as far as temperatures are concerned.

 

[transpartsnow]

Here my thoughts with 28 years building transmissions and owning one of these Rams. First everyone says something about the tires.... Not going to make that much difference with that weight. Would be better if you had 4:88 gears but not going to overheat your transmission.

Buy a deep alumumin transmission pan that holds more oil and the thermo bypass kit for the cooler lines and the filters with a steel adptor for the spin on filter. I use the Revmax and have many customers that are happy.

Here is why I said to do this way. 1 You pull the transmission pan, is there metal in the pan? 2 is the screw on filter tight and good shape? 3 If yes two the first two things, install filters and steel adapto of filter. The deep pan makes a big drop in temps, replace thermo block.

Go for a long hard drive I bet your temps never get above 160. oh and check trans cooler size. How big is it and can you find a bigger one. If you spend your money on these parts they will never go to waiste. This will save a 68rfe transmission and get 300K out of one if done when was new.

Jarad Warren
Trans Parts Now

 

[dhay13]

I really don't think your tires are causing this issue. Definitely not helping but not the cause in my opinion. These trucks are tanks and that little bit of difference shouldn't cause those issues. I still think there is a mechanical issue. But I do like the deeper pan idea. Finned or tubed will help with cooling too.

 

[Chuck962500]

I have 3.73 gears with 2 inch spacers up front and 35" tires. Same issues . my fix was real simple the tranny cooler line leaving the radiator cut and added a hayden oil cooler mounted drivers side of the radiator.then back to tranny...the stock radiator can not cool both engine and tranny under heavy load...adding the external cooler after the radiator before it returns to tranny...this works!! Cooled once through radiator then then the external cooler.this ensures the fluid is below radiator temp as it goes back to tranny..cheap fix and it totally works i tow overloaded all the time in a gasser 2500

 

[Chuck962500]

Add the external oil cooler it works!