Just returned from a trip to Yellowstone with the wife and kids towing a 2k lbs pop up, 4500 miles round trip with lots of cool stops in between...

definitely use 3 and not OD as the tranny temp goes up quick with the slippage, even in 3 with tow haul mode engaged I was reaching temps of 220+ in the Rockies.

Add an aux tranny cooler if you don't have one

Use premium fuel at high altitudes as it stopped any knocking / pinging FYI some areas use 10% ethanol further reducing power to an already oxygen starved engine

Use the tow haul mode if you have an aux or trailer battery as the mode has the alt put out a higher voltage for charging 2 batteries.

use the lower gears for going down hills as this really saved on the brakes and even at that they got warm enough to smell....

 

seems sad that a vehicle of this size with a 320 hp V8 has issues with a 2k lb pop up and some extra weight...I would think it should tow w/o breaking a sweat, but I assume you only had issues in the mountains. what speed were you able to maintain in the mountains?

other than that great tips - thank you

 

typically I could maintain about 35 to 45mph on grades of 8-14% with a down shift to 2nd I suspect the thinner air had some impact and lower pressures at altitudes of 8k plus...
I was surprised at how quickly the tranny temp did go up, it ran for the most part in the 187 to 205 range for the most part while towing and runs about 158 to 167 without any load in ambient temps of 44F to 65F.

I am going to add the aux cooler and have the tranny serviced at the recommended interval of 50k

 

ya those grades and altitudes are probably a beat down on this engine/transmission. We need a duramax option!

 

I love the towing capacity of my new Tahoe... 6 speed + factory brake controller + aux cooler up front and center... all factory.

Tows the 26' boat MUCH better than my '95 did... I feel I could tow it anywhere now, no problem at all. Even leave the A/C on max the whole time.

Does tend to kill the MPG, but what do you expect from 6,000lb load?

 

it does sound like it towed hard for a pop-up. A tranny cooler should help alot. I pull my 7,000 pound plus travel trailer in overdrive and do just fine. even on a 90+ day trans never gets over 200. Mpg is not that great but not much you can do about 10 mpg. yes we do need a duramax option.

 

Well that was the good part, I have not averaged out my MPG yet but I never got below 14mpg the whole trip, i would guess my average was about 16-17mpg over all for the whole 4500 mile trip. I'll add it up this evening and update...

 

I bet the 6 speed does a better job than the old 4 speed (at least it should) -in2pro what year do you have?

 

I have an 07 Tahoe 5.3 4spd Auto but I don't recal off the top of my head if I have the 3.73 or the 3.42

 

We have an 07 Yukon 4x4 and mostly only use it to tow our 3500# travel trailer. It does have the factory trans cooler and the 3.73 gears and we have never been over 205 and we always leave in hot country (Phoenix) and go north and are always pulling grades in CA, OR & WA in the summer. The factory or other cooler will help a lot. My friend who travels with us bought his 08 Tahoe 2wd without a cooler and the dealer installed the factory one for him, don't recall his temp figures before and after though. I also never tow the trailer in Tow Haul mode anymore because in mine you have to be doing around 62 mph to keep it in high and in CA the 55 mph limit will not allow that, no issues with keeping the battery charged either as it puts 13.6 volts into the trailer when running per the digital voltmeter in the trailer. We run in overdrive also, of course shifting down manually when needed on long grades up or down. Most 4x4's had the 3.73 and the 2x2's had the 3.42