Looking at a 2015 GMC Sierra 1500 SLE, what issues to look for?

[mikeyk101]

Before thinking the fluid is low  make sure to check hot fluid level.

 

https://www.1aauto.com/how-to-check-and-fill-transmission-fluid-14-19-chevy-silverado/video/47171

[steelerdude15]

5 hours ago, No Tyme said:

Completed the Pill Flip yesterday and I believe I lost a couple of tables spoons of fluid if that. I did check trans fluid and it seems low, with temp about 100 degrees and just having the transmission flushed at the dealer a month ago I would think it would at least be in the safe range... ended up just below it.

I will check again and if the level remains below the safe range I may add a bit to bring it up.

A cold check is done at 80 to 90 degrees F and a hot check, the more accurate check is done when your fluid is 160 to 200 degrees F.

[16LT4]

4 hours ago, steelerdude15 said:

A cold check is done at 80 to 90 degrees F and a hot check, the more accurate check is done when your fluid is 160 to 200 degrees F.

My BMW with GM 6L45 trans doesn’t have a dipstick and specifies that fluid leveling is done at 30-50*C. Operating temp is 92*C. The difference between the two is a not insubstantial amount of fluid, at least half a cup, so temp does make a difference. 
 

OP, I’d add 10oz of Lubegard Red to that trans tomorrow. Thank me later. 

[pokismoki]

19 hours ago, 16LT4 said:

My BMW with GM 6L45 trans doesn’t have a dipstick and specifies that fluid leveling is done at 30-50*C. Operating temp is 92*C. The difference between the two is a not insubstantial amount of fluid, at least half a cup, so temp does make a difference. 
 

OP, I’d add 10oz of Lubegard Red to that trans tomorrow. Thank me later. 

what year and model BMW??  the bimmers and GM cars have a smaller trans pan , they would do good if you can install the truck pan on those cars it adds about an extra 2 quarts i believe

Edited August 7, 2022 by pokismoki

[16LT4]

7 hours ago, pokismoki said:

what year and model BMW??  the bimmers and GM cars have a smaller trans pan , they would do good if you can install the truck pan on those cars it adds about an extra 2 quarts i believe

‘08 E83 with GM trans. The 45 has a different pan from the 50. I’ve got 190k miles on it with zero issues so I’m not worried about the fluid quality, I drain/fill once a year. Operating temp is also in the 150-160*Fs. I have no doubt it’ll go another 200k, just like every other GM trans We’ve ever had. 
 

Factory 8mm Allen drain plug stripped a while ago, and I replaced with 14mm GM hex plug, same as I have in the pan of my 6L80 in the K2. 

[16LT4]

7 hours ago, pokismoki said:

what year and model BMW??  the bimmers and GM cars have a smaller trans pan , they would do good if you can install the truck pan on those cars it adds about an extra 2 quarts i believe

‘08 E83 with GM trans. The 45 has a different pan from the 50. I’ve got 190k miles on it with zero issues so I’m not worried about the fluid quality, I drain/fill once a year. Operating temp is also in the 150-160*Fs. I have no doubt it’ll go another 200k, just like every other GM trans We’ve ever had. 
 

Factory 8mm Allen drain plug stripped a while ago, and I replaced with 14mm GM hex plug, same as I have in the pan of my 6L80 in the K2.