2016 Yukon XL SLT Transmission Temperature

[2001 TX Tahoe]

2016 GMC Yukon XL SLT 4WD 97,000 miles. Normal transmission operating temperature is around 196 degrees. This summer in Colorado, while in 4WD off-road, temps climbed up to 240. Later, on a 2-lane road with some steep grades, temp got up to 255. It was 55 degrees or so outside. I didn't notice any adverse affects other than the high temperature. Is this normal considering the circumstances?

 

[B-train]

It is normal, and very detrimental. GM has a new revised thermostat to lower the temp. There are also after market kits to block it open so it will cool like a transmission always USED to.

It was added to help meet CAFE requirements.......at the ultimate cost to the consumer. I'd look at other posts about 6L80 trans temp and I'm sure you'll find TONS of info, bulletins, and part numbers.

I'd also get that fluid flushed and a new filter asap since it got that hot and has 97k on it - assuming it's never been serviced (?)

For perspective: my 2008 denali with the 6L80 trans (sans thermostat) runs about 135 - 145 average. Climbing 12k peaks in CO last summer it got up to 210-217 going slow in low gears, gravel roads, not much airflow. I always let it idle after hard runs for quite some time to cool stuff off. Just something to compare with.

I'm sure others will chime in as well.

 

[Doubeleive]

2016 GMC Yukon XL SLT 4WD 97,000 miles. Normal transmission operating temperature is around 196 degrees. This summer in Colorado, while in 4WD off-road, temps climbed up to 240. Later, on a 2-lane road with some steep grades, temp got up to 255. It was 55 degrees or so outside. I didn't notice any adverse affects other than the high temperature. Is this normal considering the circumstances?

you can use this

. TRANSGO 6L80, 6L90, Cooler Flow Bypass 2016+ 8L90, 2017-19 Allison 1000 | eBay

2014-on 6L80, 6L90, 2016-on 8L90, 2017-19 Allison. An easy, no-hassle cost-effective drop-in Cooler Flow Bypass Delete Kit for General Motors 6L80, 6L90, 8L90 and Allison transmissions. Fits 2014-on 6L80, 6L90, 2016-on 8L90, 2017-19 Allison.

www.ebay.com

and then add a tru cool or something as well
I have my thermostat bypassed, trucool 40k, and a B&M deep transmission pan

 

[Rygrego]

I have the new thermostat and a Mishimoto trans cooler and my temp never exceeds 160 degrees even in 115 degree Arizona summer. Not the cheapest cooler but by far the most solid plug and play custom I've seen. Before the thermostat change and cooler addition it was always at 194 - 210+.

 

[2001 TX Tahoe]

Thanks for the feedback!