2013 new owner towing report

[cycho]

Yeah, 135-deg F is not that bad. I'd be MUCH more concerned with the 235-deg F coolant temps. Any were you running in second? No wonder the engine got so hot.

Yeah well I was going up a 7% grade and ran out of options in 3rd

 

[cycho]

Something is not right. Either the trans temp sensor is bad or you are talking C.

I’m in Phoenix also and with an LTZ with all the options including K5L cooling package with external trans cooler and 3.42 rear end and my trans temps are 185-195 NOT towing in the Phoenix heat at around 110 degrees. With a 21 ft 4000lbs of boat I’m about 200 degrees on the highway.
Up to the rim is more extreme for sure. I tow a 7000 lb 10ft high travel trailer and there are some beast mountains for sure. I wouldn’t do it with my Tahoe unless I had to. I did it with my heavily modded 99 Tahoe and it was at its limit but only for 1 year till I got the 2000 F350 CC Dually 7.3 with mods.

I run a little over 200 in the Phx heat. An I-17 trip from McDowell North to Peoria and I'm 215 with the 20ft trailer loaded with one Harley Trike. Back South empty is around 207. Never had a trans temp gage so I had no idea what it should be.

 

[cycho]

So, let me get this straight, you're worried about your transmission getting up to 135°? Are you talking Fahrenheit or Celsius? I'm honestly very skeptical that your transmission stayed below 135°F in 100-degree heat pulling a 4,000-lb trailer with no trans cooler. Are you sure the previous owner didn't install an aftermarket cooler? These trucks are designed to have the transmission running at 180-190° F. My Suburban, with the factory trans cooler, generally runs 100° hotter than the outside temperature when I'm NOT towing. I see no way your transmission stayed that cool without an external cooler.

Sorry make that 235°...

 

[Costal_Cat]

Hi,
I just posted this over in https://www.tahoeyukonforum.com/threads/towing-and-temperature-issues.112752/page-3#post-1359846

I'll post below for ease of reading but do as @swathdiver suggest do your fluids and then get that TruCool installed and you will be fine....

*************** SNIP****************

Just thought I would post my experiences out there based on my towing.

2012 Denali XL. I got the truck with around 80k on it I think and now have around 135k. I have posted about the temp and towing in several threads but here is a recap of what I have done over time. I like to do one thing at a time and then see how that affects the truck before moving on to the next thing.

I tow a bit mostly in the SE up and down 95 and out 40 to Tennesse and the NC mountains. I have slowly been working on the towing setup. I added bigger and better bump stops in the rear, new shocks and compressor for the rear, converted to passive vs eShocks when I did that. Replaced the trans filter and replaced the fluid. I have flushed it myself by doing the disconnect from the radiator with 3/8th tubing into a 5-gallon bucket while one daughter is filling with new and the other daughter is turning the engine on and off until it was pumping out clean. Flushed the cooling system completely and refilled with dex-cool. That is pretty much the order I approached things and each item improved either ride, handling or temps. The last big trip that ran up the temp was in May over memorial day and the temp in NC & SC got into the 90's. On the 7 hour ride back to the NC coast from our camping trip with the travel trailer the water temp and trans were just too hot IMO. The last thing in my view was to replace the trans cooler with the TruCool 40k. So this past Thursday I did that and immediately saw a huge difference in temp control.

2.5 hour trip up I40 in this crazy heat without towing middle of the day my temp was around 178 - 185, once I hit stop and go it went up to 190's
With the new cooler and no towing in this same heat and route the temp never got about 145 in stop and go and once I was on the interstate and up to speed the temperature dropped to 135 - 142 consistently. Even Friday evening with the heat, I pulled into the driveway and the temp was reading 129 which I have never seen after driving any time of the year.

Now I have not been able to tow a long distance yet but I did grab the boat and the same route from the house to the boat ramp last week the temp was in the 180's, same trip the temp stayed around 148 and only once got up to 153 and as soon as I was moving it was back under 150 in just a few minutes.

So all the things I have done I know have helped incrementally but the TruCool has been the best so far in my view for temp control....

 

[swathdiver]

I'll check the gearing again tomorrow, but the 2 speed TC was a big reason for my purchase.

Four Low has gotten us out of a few jams of our own making while playing off-road. 4LO also made some really sandy stretches of Daytona Beach easy peasy.

 

[intheburbs]

Four Low has gotten us out of a few jams of our own making while playing off-road. 4LO also made some really sandy stretches of Daytona Beach easy peasy.

4LO allowed me to pull a 20-ton garbage truck out of a ditch.

 

[cycho]

Hi,
I just posted this over in https://www.tahoeyukonforum.com/threads/towing-and-temperature-issues.112752/page-3#post-1359846

I'll post below for ease of reading but do as @swathdiver suggest do your fluids and then get that TruCool installed and you will be fine....

*************** SNIP****************

Just thought I would post my experiences out there based on my towing.

2012 Denali XL. I got the truck with around 80k on it I think and now have around 135k. I have posted about the temp and towing in several threads but here is a recap of what I have done over time. I like to do one thing at a time and then see how that affects the truck before moving on to the next thing.

I tow a bit mostly in the SE up and down 95 and out 40 to Tennesse and the NC mountains. I have slowly been working on the towing setup. I added bigger and better bump stops in the rear, new shocks and compressor for the rear, converted to passive vs eShocks when I did that. Replaced the trans filter and replaced the fluid. I have flushed it myself by doing the disconnect from the radiator with 3/8th tubing into a 5-gallon bucket while one daughter is filling with new and the other daughter is turning the engine on and off until it was pumping out clean. Flushed the cooling system completely and refilled with dex-cool. That is pretty much the order I approached things and each item improved either ride, handling or temps. The last big trip that ran up the temp was in May over memorial day and the temp in NC & SC got into the 90's. On the 7 hour ride back to the NC coast from our camping trip with the travel trailer the water temp and trans were just too hot IMO. The last thing in my view was to replace the trans cooler with the TruCool 40k. So this past Thursday I did that and immediately saw a huge difference in temp control.

2.5 hour trip up I40 in this crazy heat without towing middle of the day my temp was around 178 - 185, once I hit stop and go it went up to 190's
With the new cooler and no towing in this same heat and route the temp never got about 145 in stop and go and once I was on the interstate and up to speed the temperature dropped to 135 - 142 consistently. Even Friday evening with the heat, I pulled into the driveway and the temp was reading 129 which I have never seen after driving any time of the year.

Now I have not been able to tow a long distance yet but I did grab the boat and the same route from the house to the boat ramp last week the temp was in the 180's, same trip the temp stayed around 148 and only once got up to 153 and as soon as I was moving it was back under 150 in just a few minutes.

So all the things I have done I know have helped incrementally but the TruCool has been the best so far in my view for temp control....

Thanks, should I bypass the radiator when installing the TruCool or run them in tandem?

 

[Costal_Cat]

Thanks, should I bypass the radiator when installing the TruCool or run them in tandem?

Do you have a stock Cooler? If so just directly replace that. If not the process is a little more entailed but mine, which replaced the little stock one, does go through the radiator and I kept it that way.

 

[swathdiver]

Thanks, should I bypass the radiator when installing the TruCool or run them in tandem?

Keep the radiator cooling; install the external one so the fluid goes into the radiator BEFORE the TruCool.

Whew, I wrote that backwards, fixed now.

 

[cycho]

Do you have a stock Cooler? If so just directly replace that. If not the process is a little more entailed but mine, which replaced the little stock one, does go through the radiator and I kept it that way.

The fluid goes thru the radiator before or after the cooler?