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Is this how most dealers do a trans service on MQE 8 speed?   See link below.


I would like to order some  fluid from Black02Silverado and then test it.  I am too crippled to do a pan drop anymore and since the filters on these things are screen doors on submarines I would like to do the fluid exchange by machine pump.  


Is this the procedure a dealer will do from the stand pipe fixture and trans oil cooler block assembly with adapter. No dipstick on this 2022 LTD Trail Boss. 




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Found this here but its not specific about what fluid exchanges are being done in 2022 with the newer 8 speed with no dipstick. 


Edited by customboss
add other dated thread about 8 speed service at dealers
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  • 2 weeks later...

I posted a while back about the complete procedure, including torque specs etc.  I dont know where the post is but if you do a search you will probably find it.  Hell, it may be a response in the post you just identified.

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  • 4 months later...
On 5/31/2022 at 12:51 PM, Gangly said:

Attached in PDF format is how they flush the fluid.  A simple drain and refill is a different procedure.


8L90 flushing proceedure.pdf 779.03 kB · 28 downloads

Looks like I could do this at home DIY flush in the driveway by:
1. Drop pan, remove old fluid and clean pan, replace filter.
2. Install pan and add 4 quarts of fluid.
3. Remove the cooler block, inserting some poly line in the cooler port on side of transmission towards front of vehicle.
4. Fill transmission with 4 quarts of new fluid.
5. Run engine for 45 - 30 seconds to flush torque converter. Repeat until fluid is clean coming out of poly line.
6. Blow cooler lines out with compressed air
7. Replace cooler lines onto side of transmission.
8. Fill with new fluid and check level.

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