2022+ silverado/sierra transmission temp

[kickass audio]

Hi everyone, I am in the process of trying to trade my 2014 silverado for a 2023 silverado or sierra and had a question about the transmission temp. I know on my 14 I had a small amount of weeping with the trans and oil cooler lines so I replaced them and with the trans lines I also installed a surecool transmission thermostat bypass kit which greatly helped bring the trans temps down. Is the high temp issue a problem on the new 2022+ 10 speed transmissions too or has that since been fixed? I couldn't find a bypass kit for the 10 speed trans cooler so I wasn't sure how hot normal driving temps would get the trans.

[Dirk13]

Not an issue.

[MrMagloo]

I'd read some other threads.  I'm a little uncomfortable with the 190-195 ave temps I'm seeing but the dealer says this is totally normal.  I've driven a number of other recent Silverados and Sierras and they are all the same.  Seems too hot for me, especially when I have the Diesel Max Tow.  

[newdude]

11 hours ago, kickass audio said:

Hi everyone, I am in the process of trying to trade my 2014 silverado for a 2023 silverado or sierra and had a question about the transmission temp. I know on my 14 I had a small amount of weeping with the trans and oil cooler lines so I replaced them and with the trans lines I also installed a surecool transmission thermostat bypass kit which greatly helped bring the trans temps down. Is the high temp issue a problem on the new 2022+ 10 speed transmissions too or has that since been fixed? I couldn't find a bypass kit for the 10 speed trans cooler so I wasn't sure how hot normal driving temps would get the trans.

 

 

10 speed thermostat is full open at 143F.  The TBV is internal on all 10 speed with gas engine except on the 3.0 Duramax where it is external.  

Edited September 22, 2023 by newdude

[MrMagloo]

It opens at 143F and it doesn't stabilize for another 50F higher?  If it opens at 143F, at what temp is it fully open?  And, can you remove the T-Stat or do you have to go with that PPE Bypass Block? I think I'd rather keep the stock housing to avoid the dealers prying eyes, if I can remove the stock T-Stat.

 

BTW, here's that other thread:  

 

Edited September 22, 2023 by MrMagloo

[newdude]

22 minutes ago, MrMagloo said:

It opens at 143F and it doesn't stabilize for another 50F higher?  If it opens at 143F, at what temp is it fully open?  And, can you remove the T-Stat or do you have to go with that PPE Bypass Block? I think I'd rather keep the stock housing to avoid the dealers prying eyes, if I can remove the stock T-Stat.

 

BTW, here's that other thread:  

 

 

 

I should correct my post.  Full open is 143F.  Its a 15-20 degree temp swing from start to open to full open so it should start to open around 123-130F.  

 

That OP might have a twisted cooler line which is a known possible overheat concern GM has seen.  

Edited September 22, 2023 by newdude

[newdude]

1 hour ago, MrMagloo said:

I'd read some other threads.  I'm a little uncomfortable with the 190-195 ave temps I'm seeing but the dealer says this is totally normal.  I've driven a number of other recent Silverados and Sierras and they are all the same.  Seems too hot for me, especially when I have the Diesel Max Tow.  

 

 

Duramax will run warmer than gas due to the design of the cooling system loop.  

 

3.0 Duramax is like the 2.7 Turbo in where it has that Active Thermal Management with the water flow control valve.

 

The transmission cooling loop is as follows.  Fluid flows from the transmission to an oil to water heat exchanger bolted directly to the transmission.  ATF goes in and out through two passages, engine coolant via two tubes on the exchanger.  From that heat exchanger, it will then flow to the TBV.  If closed still, the TBV will then loop back to the transmission.  When the TBV is open, ATF will go from the transmission, through the heat exchanger, out to the auxiliary cooler, then back to the transmission.  

 

The heat exchanger being in the loop is why they run around water temperature.  Its oil to water heat exchanging, and then when the TBV is open, its adding oil to air regulation.  

 

10 speed gas don't use ATM and a heat exchanger.  Its transmission direct out to a standalone cooler and back.  TBV full opens at 143F and then attempts to maintain.  Obviously towing and airflow are a factor as well.  

 

So 190-195F just driving around is considered normal on the Duramax.  Bypassing the TBV would just delay that inevitable temperature as its still flowing through that oil to water heat exchanger.

Edited September 22, 2023 by newdude

[Gangly]

8 minutes ago, newdude said:

 

 

Duramax will run warmer than gas due to the design of the cooling system loop.  

 

3.0 Duramax is like the 2.7 Turbo in where it has that Active Thermal Management with the water flow control valve.

 

The transmission cooling loop is as follows.  Fluid flows from the transmission to an oil to water heat exchanger bolted directly to the transmission.  ATF goes in and out through two passages, engine coolant via two tubes on the exchanger.  From that heat exchanger, it will then flow to the TBV.  If closed still, the TBV will then loop back to the transmission.  When the TBV is open, ATF will go from the transmission, through the heat exchanger, out to the auxiliary cooler, then back to the transmission.  

 

The heat exchanger being in the loop is why they run around water temperature.  Its oil to water heat exchanging, and then when the TBV is open, its adding oil to air regulation.  

 

10 speed gas don't use ATM and a heat exchanger.  Its transmission direct out to a standalone cooler and back.  TBV full opens at 143F and then attempts to maintain.  Obviously towing and airflow are a factor as well.  

 

So 190-195F just driving around is considered normal on the Duramax.  Bypassing the TBV would just delay that inevitable temperature as its still flowing through that oil to water heat exchanger.

Great insight.

[redwngr]

1 hour ago, newdude said:

 

 

10 speed thermostat is full open at 143F.  The TBV is internal on all 10 speed with gas engine except on the 3.0 Duramax where it is external.  

 

I keep reading that, but my '21 LM2 always stabilized in the 180-190 range, my '23 LZO always stabilizes in the about 190-200. 

 

Ambient doesn't matter so they must somehow be controlled to those temperature ranges. 

 

Perhaps the temp is different on the 3.0 versions of the speeds?

(MCQ and MQB vs MHS, MNT and MQE)

 

 

 

EDIT:

I see this was addressed in posts after the one I quoted...

Edited September 22, 2023 by redwngr

[MrMagloo]

Thanks for that detailed insight ND.  What I don't get is all of these guys out there trumpeting the PPE Bypass Block, saying it alone will drop the temps ~25F and these temps hold up over great distance while towing?  I just think this ~190+F temp is too high.  I'd feel much better in the 170's, where all my past trucks ran.

Edited September 22, 2023 by MrMagloo

[newdude]

26 minutes ago, MrMagloo said:

Thanks for that detailed insight ND.  What I don't get is all of these guys out there trumpeting the PPE Bypass Block, saying it alone will drop the temps ~25F and these temps hold up over great distance while towing?  I just think this ~190+F temp is too high.  I'd feel much better in the 170's, where all my past trucks ran.

 

 

I suppose the idea behind that would be the fluid starts off cooler and during some period of time while towing?  Combine the TBV and the PPE upgraded cooler they offer would permit the temps to stay closer to the 190-210F mark instead of getting hotter while towing (reduce the time to heat soak).  

\\

Edited September 22, 2023 by newdude

[MrMagloo]

I guess I could start with the bypass and add from there.  I am planning to buy a toyhauler that has a dry weight of 7,000lbs and a capacity of 11,000lbs, but with the Harley at 900lbs and say other gear of around 1,000lbs, I'm hoping to keep the GVW around 9,000 or below, if possible.  In the midwest, we don't have to deal with much in the way of steep grades, so I'm hoping this 13K capable truck will handle it. Imho, 13K with a 1/2 ton is kind of nutty so I'm hoping running at roughly 2/3rd that will work out ok.  I guess we will see.

[kickass audio]

Thank you everyone for your input I really appreciate it. I only went for a short test drive on the new silverado, approximately 20 minutes but the trans temp went up to 148 and as soon as I got on the gas and moved a little it dropped down to 134 instantly.

 

I have to say so far with it being a demo vehicle with 3800 miles on it and the 10 speed with a 5.3l it drives fantastic! I don't have the jerking feeling when changing gears like my 6l80 gave and I can't feel anything when it's supposed to be changing the cylinder firing with AFM. The only thing it will take me awhile to get used to is the new shifter in the center console and when I leave the auto-stop turned on it gives you a feeling like you were bumped from behind (make me get really scared on the test drive as I thought I was hit lol).

[onewheat]

My '14 with a 6-speed (6.2) consistently ran around 200°F when not towing and would move up to maybe 210° towing.  My 2023 with the 10-speed (also 6.2) runs in the mid-140° range and when towing I've seen 170°s - this is independent of ambient temperature.  

 

Even 200°F is a non-issue for transmission temperature.  My transmission guy told me to start thinking about it if I hit around 230°F and up.