Transmission cooler inside radiator

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BG1988

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Where'd you get these numbers and to which transmission(s) do they pertain?
varnish starts to form at around that temperature.. it clogs the little tubes inside of it.

also more then likely the transmission has cooler lines to the radiator, if it does not have the Aux cooler..

a normal transmission in the tahoe runs between 155-165F without a tow load ..

that is why a bought one that had not been used for towing...


a 2012 hyhoe that had been used for towing had a faulty transmission and made a horrible screeching noise coming from the transmission ( CVT slipping)..


among other issues such as oil low PSI/ no psi... something seemed off..


a 2009 I also suspect it had been using for towing
(auto stop lag issues) faulty HVDC battery..


more then likely the person who had it used to the EVT to tow or did not use tow mode (aka normal 4 speed mode/generator mode)..
 
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swathdiver

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varnish starts to form at around that temperature.. it clogs the little tubes inside of it.

The normal operating temperature for the 4-speeds is 180-200 degrees. The warnings don't come on until the temperatures exceed 260 degrees. The 6-speeds have a wider operating range, 160-200 and a little higher for the warnings. If one were to run them over 230 say while towing, fluid life is greatly diminished and the interval should be shortened.

I didn't know the Hybrid transmissions were CVT style, yuck. But I think it cool that they have two electric motors.
 

BG1988

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The normal operating temperature for the 4-speeds is 180-200 degrees. The warnings don't come on until the temperatures exceed 260 degrees. The 6-speeds have a wider operating range, 160-200 and a little higher for the warnings. If one were to run them over 230 say while towing, fluid life is greatly diminished and the interval should be shortened.

I didn't know the Hybrid transmissions were CVT style, yuck. But I think it cool that they have two electric motors.
It's a High Quality CVT. by Allison .. a $10,000 transmission and not a typical CVT. 08-09
( the 2010-2013 have a somewhat cheaper revised version ??? and higher 0-60 times compared to 08-09)

the only way you can break the CVT in it, is by towing and NOT using tow mode as recommend..(or doing something stupid)..basically the tow mode changes it to a normal 4 speed automatic.. i'm sure you will get the same MPG as the reg tahoe..

maybe 1-2mpg more( because it has only idler pulleys, alternator delete , A/C delete, PS delete)


The shifting is soooo smooth it's nearly undetectable.. the only thing you will feel is the engine starting up or shutting down.....

I test drove a 2015 Toyota corolla and the CVT was all ready slipping at 15,000 miles.. that is why i did not buy it the slipping was slight but detectable

but those have a physical flaw..
they try and fix with a software update LOL..
 

swathdiver

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I noticed that the 2009 Escalade's had a 3.42 gear, all the others 3.08s. That'll help with get up and go. Wonder why they stopped that?

Interesting transmission!
 

BG1988

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http://autotk.com/0-60-times/chevrolet/tahoe-hybrid/
I noticed that the 2009 Escalade's had a 3.42 gear, all the others 3.08s. That'll help with get up and go. Wonder why they stopped that?

Interesting transmission!

0-60
tahoe
2008/09
6.3 - 6.4 sec
Escalade
2009
6.75 - 6.85 sec

Tahoe still a bit snapper then the Escalade..

tahoe
2010/11/12/13
8.1 - 9.2 sec

Escalade
2010/11/12/13
8.7 - 9.2 sec


something was changed that increased the 0-60 times... suspect cheaper poor quality parts/ with a speed/accelerator limiter.. :(
 

Tonyrodz

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The normal operating temperature for the 4-speeds is 180-200 degrees. The warnings don't come on until the temperatures exceed 260 degrees. The 6-speeds have a wider operating range, 160-200 and a little higher for the warnings. If one were to run them over 230 say while towing, fluid life is greatly diminished and the interval should be shortened.

I didn't know the Hybrid transmissions were CVT style, yuck. But I think it cool that they have two electric motors.
20190125_184246.jpg
 

BamaDawg

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I watch my temp all the time too because I’m weirdo. It runs about 120-130’
2011 ppv Tahoe

Do you have a cooler or deep pan on yours?

What brand ATF fluid are folks running? And has anyone used a friction modifier with success of lowering the temperature or are the synthetic ATF good enough?
 

massivespl

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Do you have a cooler or deep pan on yours?

What brand ATF fluid are folks running? And has anyone used a friction modifier with success of lowering the temperature or are the synthetic ATF good enough?

Mines got a front mount cooler. Pretty sure I have stp fluids. I could be wrong on brand of fluid
 

swathdiver

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Do you have a cooler or deep pan on yours?

What brand ATF fluid are folks running? And has anyone used a friction modifier with success of lowering the temperature or are the synthetic ATF good enough?

ACDelco here. Grumpy Bear over at GM-Trucks forum picked up about 1 mpg by switching his transmission fluid over to Redline. Might do it myself next time around.
 

BamaDawg

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Question? Finally got time to pick up a transmission cooler nice larger 11 x 12" unit. My question is - is it better to just bypass the whole in radiator cooler or to use this inline with it. I have the Yukon Hybrid and I have read on here that the coolant will help bring down the trans temp but how can that be when the engine temp is at a constant 210 degrees when warmed up and driving. And we are looking at the trans temp at an average of 167-175 without the cooler. In my mind I am thinking once up to engine temp the current OEM setup is raising my trans temp. Helpful thoughts? Has anyone else by passed the whole OEM and just run the external cooler? if so what temps are you seeing on normal highway 70mph driving.
 
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The coolant in the radiator is cooler than engine temp.

Coolant enters the block, heads, then intake picking up heat as it travels and exits the intake where the thermostat is to the radiator to cool down.

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18
 

BG1988

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Question? Finally got time to pick up a transmission cooler nice larger 11 x 12" unit. My question is - is it better to just bypass the whole in radiator cooler or to use this inline with it. I have the Yukon Hybrid and I have read on here that the coolant will help bring down the trans temp but how can that be when the engine temp is at a constant 210 degrees when warmed up and driving. And we are looking at the trans temp at an average of 167-175 without the cooler. In my mind I am thinking once up to engine temp the current OEM setup is raising my trans temp. Helpful thoughts? Has anyone else by passed the whole OEM and just run the external cooler? if so what temps are you seeing on normal highway 70mph driving.
159-162F on the GM 2ML70

it's summer time 100+F
 

Doubeleive

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http://autotk.com/0-60-times/chevrolet/tahoe-hybrid/


0-60
tahoe
2008/09
6.3 - 6.4 sec
Escalade
2009
6.75 - 6.85 sec

Tahoe still a bit snapper then the Escalade..

tahoe
2010/11/12/13
8.1 - 9.2 sec

Escalade
2010/11/12/13
8.7 - 9.2 sec


something was changed that increased the 0-60 times... suspect cheaper poor quality parts/ with a speed/accelerator limiter.. :(
Those numbers must be for hybrids?, no way in hell my (6.2l /3.42 same as the escalade) 2012 denali xl takes 8 seconds to reach 60, i'm hitting 80+ on a typical onramp, those numbers are wrong most places give 6.4-8.3, my 03 silverado (5.3) is rated 8.4 and my Denali overtakes the silverado pretty much right out the gate
 

BG1988

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Those numbers must be for hybrids?, no way in hell my (6.2l /3.42 same as the escalade) 2012 denali xl takes 8 seconds to reach 60, i'm hitting 80+ on a typical onramp, those numbers are wrong most places give 6.4-8.3, my 03 silverado (5.3) is rated 8.4 and my Denali overtakes the silverado pretty much right out the gate
the 08/09 have unlocked acceleration limiter for the hybrid she'll take off on you if your not paying attention...

in 09(possibly MY) the acceleration was governed which is why the 0-60 times are different on the LZ1 setup compared to the LFA
the electronics were changed..


The reverse is unlocked as well. don't let the HYBIRD logo fool you I like screwing with people on the freeway trying to pass me lol I hear their 4 banger revving to 4-5,000 rpm


then i jump to 2100-2200 not letting them pass me on the right... while speeding off



it useful on the ca110 stop sign entrance I can go 0-50 in 4.5-4.8 seconds
from 50 to 60mph it goes to ICE only when goes from 50 to 60 painfully slow.. other wise the 0-60 would be 5.5seconds if it did not have the "limitation"

(because it based on load, but the electrical motors will work above 50mph just like AFM)

When I put it in M.



When in D gear it's a bit slower acceleration on the EVT 0-60 is 8.5-9 seconds which is fine most of the time..



The thing i like the most is the handling is pretty good better then my old car :)
 
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Doubeleive

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just to update on this I have had to move my trucool down behind the front lower bumper grill (cut holes behind the plasti-chrome for airflow) because in the summer the trucool would make the engine temp go up more than it should, especially if driving it hard, on a upgrade or higher elevation.
doing so gives me around 180deg as a average high on the transmission (usually less if not pushing it hard), which is fine
the highest it has ever reached is like a short peak of 223 driving a slow upgrade at around 6000ft with ambient temps of around 80-90

and I have managed to get it 0-60 in 6.4, 12 denali xl awd. verified with onboard obd interface
 

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