Transmission Temp

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cycho

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Reference:2013 LTZ that I have owned for a few months.

Drove home from our cabin Sunday pulling a small enclosed trailer and noticed that my transmission reached 203° by the time I pulled into the driveway. Never saw it this hot. But it makes sense being that it's cooled through the radiator...right? Outside temp was in the 90's.

Just wondering if it's normal because I'll soon be pulling a much larger trailer in the Arizona Heat.

thanks
 

Doubeleive

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Reference:2013 LTZ that I have owned for a few months.

Drove home from our cabin Sunday pulling a small enclosed trailer and noticed that my transmission reached 203° by the time I pulled into the driveway. Never saw it this hot. But it makes sense being that it's cooled through the radiator...right? Outside temp was in the 90's.

Just wondering if it's normal because I'll soon be pulling a much larger trailer in the Arizona Heat.

thanks
yes perfectly normal
 

Joseph Garcia

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As a follow-up question, at what temperature, would one consider the temperature to be excessive?
 

HiHoeSilver

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220+ is getting a little on the warm side imo. While heat is the enemy, the fluid doesn't start to break until over 300 somewhere.
 

Doubeleive

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if you are going to be hauling something bigger out there in the desert and are concerned about heat you can add a external trans cooler in addition to anything that is factory, several of the members here run the tru-cool 40k, they run about $130 online and is easy to install. I added one on mine and a B&M deep transmission pan (70392) that gives it an extra 2qt capacity. I was getting 200+ temps all the time just driving (I have a heavy foot), now my temps run about 136 +/- a few degrees it might hit 165 if i'm pushing it kinda hard and it's hot out. winter time it runs about 10 deg's lower.
 

adventurenali92

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if you are going to be hauling something bigger out there in the desert and are concerned about heat you can add a external trans cooler in addition to anything that is factory, several of the members here run the tru-cool 40k, they run about $130 online and is easy to install. I added one on mine and a B&M deep transmission pan (70392) that gives it an extra 2qt capacity. I was getting 200+ temps all the time just driving (I have a heavy foot), now my temps run about 136 +/- a few degrees it might hit 165 if i'm pushing it kinda hard and it's hot out. winter time it runs about 10 deg's lower.
This!! I was about to suggest just this for towing bigger and heavier. I have a trucool 40k cooler on my truck that I swapped the factory cooler out for! And it’s the best under hood mod I’ve done! In normal conditions I never get above 150 trans temps. I just finished a tow job for a close family friend. She has a nearly 6,000lb sea day v hull that I get to go wakebaording behind. She stores it down off the mountain in Orange County for the winter months. I bring it up to big bear to get ready for the lake. It’s a roughly 80 mile trip across the SoCal freeways and then up over 8,000 feet in elevation at the top of the drive that brings you to big bear. And my trans never went above 180 the entire time pulling the boat! The minute I went down to back part of the highway grade from the summit into town, trans temp dropped back to 150. That cooler works hard! An upgraded trans cooler is a must have option for towing in my opinion.
 

jarydM

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saving this post for future reference when I start pulling the camper in ~6 months.
 

rzabel

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I tow a lot, and in hot weather and occasional mountains. I have the stock transmission cooler for my 2500 with the 4L85E. It seems to work fine. My temperatures are always in the normal range (180F to 200F). Why would I want to get the temperatures to 135F to 165F? Shouldn't the transmission perform best when operating in the normal design range?
 
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cycho

cycho

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if you are going to be hauling something bigger out there in the desert and are concerned about heat you can add a external trans cooler in addition to anything that is factory, several of the members here run the tru-cool 40k, they run about $130 online and is easy to install. I added one on mine and a B&M deep transmission pan (70392) that gives it an extra 2qt capacity. I was getting 200+ temps all the time just driving (I have a heavy foot), now my temps run about 136 +/- a few degrees it might hit 165 if i'm pushing it kinda hard and it's hot out. winter time it runs about 10 deg's lower.
This one? https://www.amazon.com/dp/B00803CTD...olid=1K7PHQ7IUO7LV&psc=0&ref_=lv_ov_lig_dp_it
 

jamoody

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I believe an after factory transmission cooler is needed for regular towing in extreme conditions (desert heat and mountain climbs). I installed https://www.etrailer.com/Transmission-Coolers/Derale/D13502.html before my cross country trip from the east coast through the Rockies and southwest desert last summer pulling a 4000lb trailer. The transmission temperature sat at 195F most of the time at 65 mph, climbing occasionally to 201F max on a 10,000 ft assent. For occasional towing on the flat you could probably get by without a cooler. I'm told the coolant line valve opens at 195F.
 

BG1988

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I tow a lot, and in hot weather and occasional mountains. I have the stock transmission cooler for my 2500 with the 4L85E. It seems to work fine. My temperatures are always in the normal range (180F to 200F). Why would I want to get the temperatures to 135F to 165F? Shouldn't the transmission perform best when operating in the normal design range?
depends how long you want it to last service life drops as the temperature rises
 

Mickey_7106

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Personally i don't like going over 190° And I'll be worried past 220°

Reference:2013 LTZ that I have owned for a few months.

Drove home from our cabin Sunday pulling a small enclosed trailer and noticed that my transmission reached 203° by the time I pulled into the driveway. Never saw it this hot. But it makes sense being that it's cooled through the radiator...right? Outside temp was in the 90's.

Just wondering if it's normal because I'll soon be pulling a much larger trailer in the Arizona
 
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cycho

cycho

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Today we installed an 8" drop hitch, brake controller and ordered a trans cooler. Then pulled a 20 foot enclosed trailer about 40 miles. Probably around 3400 lbs with today's load. The trans temp got to a high of 208° once we were on city streets. On the freeway it stayed just below 200° as long as we were moving. Air temps were in the 80's.

I was looking for a 10" drop but 8" was all I could find and I was in a hurry. It worked better than I thought, the Tahoe does drop about an inch so the trailer is only a slight bit high in the front. Perhaps a front level kit will help bring the back down and inch?
Also I have always towed this trailer with a weight distribution hitch and sway bar. Today was without all of that. It did sway a bit but it was real windy. Friday I'll be making a 2.5 hour trip to the North so I'll see how the Tahoe/ bare hitch works out and I'll be keeping a close eye on the trans temp. We'll be traveling late at night with closer to 4000 lbs, then home during the day but empty. Fingers crossed
 

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