Towing with 2500HD/6.0L

RamblinFever · June 6, 2016

Just sold my 2014 1500LTZ CC and bought a 2016 2500LTZ CC three weeks ago. I have been towing trailers since 1979 with half and 3/4 ton Chevy or GMC pickups. This is the first one with the "tow/haul" feature that I'm towing with. I'm finding the owner's manual is very broad about towing and the dealer isn't a whole lot of help either with varied opinions. I'm expecting the tow/haul will automatically downshift as needed when climbing a grade. One of my concerns is transmission temperature. With my '92 2500 and 5.7 I installed a temp gauge and never went over 210 degrees, No one can tell me what the safe range is for towing and not overheat the trans. I drive reasonably so really not much to worry about but have seen people tow uphill quite fast. I will be towing a 2011 Heartland 30ft. fifth wheel with the Anderson hitch. I uploaded two photos but my .jpg isn't allowed on the forum.

SouthpawHD · June 6, 2016

Welcome to the forum.

These trucks are built to tow and haul, so the computer will pretty much take care of things as far as the trans temps go and shut things down before it gets out of hand. But around that 225* range is where you would want to keep a closer eye on things. Prior to that temp, don't worry about a thing.

The tow/haul feature simply stretches out the shift points, allowing the motor to rev a little higher before shifts. The tow/haul feature doesn't "automatically" downshift as needed, rather the computer system is doing that whether the T/H is engaged or not, it just allows higher RPMs as stated above.

BTW, I towed this weekend in 80* temps, pulling 8,000 pounds, and the trans temp never got above 150*.

Edited June 6, 2016 by SouthpawHD

RamblinFever · June 6, 2016

The 150 is lower than I expected. Probably won't do a trip with the trailer until July when I head to San Diego.

DBTravelers · June 6, 2016

Southpaw, I had a 2013 1500 Sierra with 5.3 and used Tow/Haul on it quite a bit as I pulled a 8500# travel trailer. I would push the button to engage T/H mode when starting on an incline, or if I needed to move into traffic a bit quicker than normal. I also used it in the mountains of CO, WY, and OR on a recent trip when the terrain was undulating. Other than that, I just let the computer take care of normal shifting and had no issues at all. We pulled across Death Valley and tranny temps hovered about 200, but that is not a problem. Traded for a 2015 3500HD Allison DRW, so until we trade for the 5th wheel we don't use T/H much yet. Congrats on the new 2500HD! Yes, we would like to see a photo of the new baby.

NitroCherokee · June 6, 2016

While mine is a different animal, I have an 04 with 6.0 and a 4L80 trans. While towing my 33' TT (8700-9000lbs going down the road) in temps around middle 80's I saw trans temps staying 190-200° a few longer grades with a head wind I did get to 205°

RamblinFever · June 6, 2016

I was hoping to post some pics but it doesn't like the file extension. Was hoping to find some FAQ to solve the problem.

Edited June 6, 2016 by RamblinFever

Nathan79 · June 6, 2016

The tow/haul button does a lot in the background that not only helps make towing more effective and better experience but also better on your tranny. Holding lower gear longer, firmer shift points/higher line pressures, TC lockup, etc all help to have lower tranny temp, less slipping and longer life when towing. Also, there are enough nannies on the tranny that will prevent any issues from temp. It will give you a message if the temp is getting too high (260 deg or so) - Trans Hot Idle Engine. Pull over and idle to let it cool down. I doubt you will ever see it.

I towed a 7500lb travel trailer up over Mt. Hood area here in Oregon and tranny temp barely got to 190.

Dex VI is supposed to be a great tranny fluid and I wouldn't worry about the temperature unless you see it go >250.

Skeld · June 7, 2016

So far I have only towed a light 3,000 to 4,000 pound trailer and it doesn't seem tow/haul is necessary with my truck for this kind of trailer. The 2500 transmission is already pretty aggressive with its shifting compared to a 1500 without tow/haul. With my 1500 I would generally use tow/haul with these trailers.

Tjeli · June 7, 2016

I have pulled 13,000 with mine. Trans temp will be a non issue for you. These new HDs have extremely good cooling systems. Here is a video of 0 - 65 with 13K lbs behind me.

http://api.viglink.com/api/click?format=go&jsonp=vglnk_146531285252112&key=5db37a1c133b6a8258388d3c5c73c75d&libId=ip5lew7d01000tul000DAagotbcuu&loc=http%3A%2F%2Fwww.silveradosierra.com%2Ftowing-trailers%2Ftowing-acceleration-video-15-hd-6-0-13k-lbs-t512497.html&v=1&out=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DleJCOXnX5BA%26feature%3Dyoutu.be&ref=http%3A%2F%2Fwww.silveradosierra.com%2Fmember%2FTJEli%2Ftopics%2F&title=Towing%20acceleration%20video.%20'15%20HD%206.0%2013K%20lbs.%20%3A%20Towing%2FTrailers&txt=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DleJCOXn%20...%20e%3Dyoutu.be

-Eli

Edited June 7, 2016 by Tjeli

SouthpawHD · June 7, 2016

I have pulled 13,000 with mine. Trans temp will be a non issue for you. These new HDs have extremely good cooling systems. Here is a video of 0 - 65 with 13K lbs behind me.

http://api.viglink.com/api/click?format=go&jsonp=vglnk_146531285252112&key=5db37a1c133b6a8258388d3c5c73c75d&libId=ip5lew7d01000tul000DAagotbcuu&loc=http%3A%2F%2Fwww.silveradosierra.com%2Ftowing-trailers%2Ftowing-acceleration-video-15-hd-6-0-13k-lbs-t512497.html&v=1&out=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DleJCOXnX5BA%26feature%3Dyoutu.be&ref=http%3A%2F%2Fwww.silveradosierra.com%2Fmember%2FTJEli%2Ftopics%2F&title=Towing%20acceleration%20video.%20'15%20HD%206.0%2013K%20lbs.%20%3A%20Towing%2FTrailers&txt=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DleJCOXn%20...%20e%3Dyoutu.be

-Eli

Pretty sure I saw your gas gauge move at the same speed your tach was moving ;)

I had to jump on it on Sunday pulling about 8,000 pounds, and was really impressed on how quickly it can get up to speed when it needs too.

newdude · June 7, 2016

Pulled a 18ft equipment trailer with an old Ferguson TO20 tractor with back blade on it a couple weekends ago, about 25 miles. I'd say somewhere total between 5000-6000lbs. Trans temp never breached 155F, pulled like a champ.

Edited June 9, 2016 by 15HDriver

avalonandl · June 9, 2016

The newer Dexron fluids are meant to perform at higher temps. A 230 trans temp is getting warm but not too hot. Over 250 is not good, and you need to cool down. There are older charts-tables floating around that show anything over 200 to be death to your tranny. These are from 10+ years ago. I have talked to powertrain engineers and they tell me the new fluids are so much better able to resist damage at the higher temps.

Avalon

DBTravelers · June 9, 2016

When pulling my 8000# travel trailer last year with my 2013 5.3 GMC 1500, I saw the temp hit 215 and was worried. Traffic was stop-and-go in 100+ degree heat. I tried finding out what temperature spells trouble in various forums, but finally just called the GMC dealership and spoke with the manager in the transmission shop. He said I would have to be up around 285 degrees for several hours of driving to start doing serious damage to the transmission and burning the fluids. He said today's engine/transmissions can run 220-230 all day long with no real issue or damage. Pulling the same rig last year in Wyoming and Colorado, I saw the temps hit 230 but only until I reached the summit and it cooled back to about 200 headed down the other side. No problems whatsoever.

SMiller · June 10, 2016

I have never seen a 6L90E get hot and I have pulled and pushed the guts out of these trucks.

My wife just got a 3/4ton Yukon (same 6.0/6L90E) and I ordered a aftermarket trans pan but really only for a drain plug as the factory pan didn't have one, will be interesting to see if there is a drop in temps as others have stated though.

okiesprayguy · June 22, 2016

My transmission temp in my 08 1500 5.3 with 3.73 rear end got up to 230 degrees when crossing the Le Veta pass in Southern Colorado while pulling a 18 ft trailer with 4 atvs. I was at about 75k miles and a little bit concerned when I got back home. So I pulled the pan and changed the fluid and gasket. I couldn't tell a bit of difference between the old and new. Feel,smell, color were all the same.