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Transmission fluid and filter change, temperature to check fluid level??

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Coming up on 45K on my truck and it's time to change the transmission filter.  I read through the filling procedure and it says get the trans temp up to 165.  I barely ever recall seeing the trans temp as high as 165 in the summer towing my camper, so I am not too confident I can get it to warm up that much in the winter idling in the driveway.  Planning to measure what comes out, but that plan can always go awry if I bathe in the pan contents.  😉  


Does anybody know how critical that temperature is to getting the fluid at an acceptable level?  I am assuming the warmer the fluid gets, the higher the level goes???  Would an extra pint really make much difference?  


Those pesky dipsticks, obviously they had to go!!!  

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I do not know for certain but when i had the GM dealer flush my this summer they mentioned it had to get up to 145° F to check it and that was taking more time.  I am sure that's an approximate.


2021 1500 10sp

Edited by elcamino
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I saw a technical bulletin a while back that gave the temp but I didnt save it and I dont recall exactly where I saw it. I believe it was something over 160 degrees. On most vehicles without a dipstick this is the time consuming part of the job. Plus once the trans is hot so are the cat's, one of which is near the side of the trans fill plug. The entire process is an epic fail in my opinion. The 1000 series was a breeze to service along with all the 3000 and 4000 series Allisons I ever worked with. Its my opinion that this is a strong indicator of GM's design. Take something that has always worked and make it much harder to maintain in order to save pennies. 

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