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Transmission Fluid level not quite right after drain and fill (8 speed)

X-Raid
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X-Raid New Member

X-Raid

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I have a 2022 Sierra, 2.7L Turbomax with MQE 8 speed, 97k miles. Purchased a few weeks ago and noticed that I had a slight shudder when cruising at highway speeds so I wanted to change the trans fluid. I found multiple threads on here about how to go about this process and felt reasonably confident about performing this job the correct way. I dropped the pan last night, drained the fluid and changed the filter and then installed a 265-931 Dorman pan with a drain plug so that I could drain it easier next time. I filled with about 7. 5 quarts of Mobil 1 Blue label LV ATF HP, turned the truck on and ran it through each gear selector for 3 seconds each and then let it get up to temp. When I took out the check plug bolt to verify the fluid level at around 98F,the fluid streamed out and never slowed to a drip even after several minutes of it draining. Im not sure how much exactly drained out, but it was at least a quart or two. It was still draining once the trans got up to 115F so I turned it off and figured I'd recheck it in the morning so that it had a chance to get back into the correct range. I checked it this morning once it got up to the 95F temp again, and there was no drip at all, so assumed it drained a little too muxh last night. With it running I pumped about 3/4 of a quart through the fill tube until it started to come out of the drain plug again, but it still continues to just steam out and never slows to a drip. Am I doing something wrong here? I feel like it should be at the correct level, but the fact that when I check it and it's streaming out makes me think something isn't quite right. 

carkhz316 Enthusiast

carkhz316

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No you're not doing anything wrong. It continues to warm up even while idling, which expands the fluid and continues to be a steady trickle. As long as its not gushing or glugging out, its fine.

 

If you want to confirm proper fluid level:

 

  -  top it off and run it to minimum check temp, cycle through the gears down to [1] pausing in each position for a couple seconds and ending back in PARK. Pull the check bolt and when its a thin line stream stick it back in and call it a day. 

newdude Senior Enthusiast

newdude

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Posted (edited)
5 hours ago, X-Raid said:

I have a 2022 Sierra, 2.7L Turbomax with MQE 8 speed, 97k miles. Purchased a few weeks ago and noticed that I had a slight shudder when cruising at highway speeds so I wanted to change the trans fluid. I found multiple threads on here about how to go about this process and felt reasonably confident about performing this job the correct way. I dropped the pan last night, drained the fluid and changed the filter and then installed a 265-931 Dorman pan with a drain plug so that I could drain it easier next time. I filled with about 7. 5 quarts of Mobil 1 Blue label LV ATF HP, turned the truck on and ran it through each gear selector for 3 seconds each and then let it get up to temp. When I took out the check plug bolt to verify the fluid level at around 98F,the fluid streamed out and never slowed to a drip even after several minutes of it draining. Im not sure how much exactly drained out, but it was at least a quart or two. It was still draining once the trans got up to 115F so I turned it off and figured I'd recheck it in the morning so that it had a chance to get back into the correct range. I checked it this morning once it got up to the 95F temp again, and there was no drip at all, so assumed it drained a little too muxh last night. With it running I pumped about 3/4 of a quart through the fill tube until it started to come out of the drain plug again, but it still continues to just steam out and never slows to a drip. Am I doing something wrong here? I feel like it should be at the correct level, but the fact that when I check it and it's streaming out makes me think something isn't quite right. 

 

 

Are you doing this on flat ground or a lift?  

 

A heavy stream should lead to like a trickling of fluid coming out.  So if it was overfull, you'd see a solid stream.  As it gets to the level point, it should thin out quite a bit and turn into a trickle.  That trickle should turn into a rapid drip.  

 

Warning: The transmission fluid level must be checked when the transmission fluid temperature (TFT) is between 35–45°C (95–113°F). If the TFT is not within this range, either idle or brake torque the vehicle to raise the fluid temperature, or shut off the vehicle to allow the fluid to cool as required. Setting the fluid level with a TFT outside this range will result in either an under or over-filled transmission. TFT>45°C=under-filled, TFT<35°C=over-filled. An under-filled transmission will cause premature component wear or damage. An over-filled transmission will cause fluid to discharge out the vent tube, possibly causing a fire that may result in serious bodily injury or severe vehicle damage, fluid foaming, or pump cavitation.
 
Note: If vehicle is equipped with a thermal bypass valve, the transmission fluid level should be checked only after the TFT has reached or exceeded an operating temperature of 90°C (194°F). Once the TFT has reached or exceeded 90°C (194°F), then turn OFF the vehicle and allow the TFT to cool back down to 35–45°C (95–113°F) before checking the fluid level as required.  Reaching or exceeding an operating temperature of 90°C (194°F) opens the bypass valve and allows the cooler to fill up with fluid, which will result in a more accurate fluid level check.

 

8 speed with the 2.7 doesn't have a thermal bypass, but that said, I would maybe consider getting it to full operating temp, and then check it the next day between that 95-113F temp range.  

 

Start around the 19:35 mark.  Its on a Camaro but same idea.  

 

 

 

 

 

 

Edited by newdude
X-Raid New Member

X-Raid

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Thanks for the replies. I was doing it on level ground, no lift. I did see the fluid transition from the steady stream to the thinner stream at one point, I just assumed it was supposed to get to more of a drip. The last time I topped it off (a few hours ago) I put the check plug back in as soon as it started to trickle. I took it for a test drive and it seems to be shifting well. I didn't notice the shudder, tomorrow on my way to work will be the real test for that though.

 

I was really surprised at how dark the fluid was. No burned smell, but it pretty much looked like used motor oil. 

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