2016 Suburban 6L80E 81K TC went out sample.

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Dec 13, 2002
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This is from our 2016 Suburban with the 6L80E transmission with 81k. It started to whine from the transmission and then we lost all our gears even reverse in just 5 miles from the noise starting. What was weird is that after turning it off and letting it sit it worked again but the whine was still there. Had it rebuilt and the shop said the TC was gone and the pump showed some wear. The fluid was changed out to AMSOIL ATL at 10k miles from new, then I did a pan drop and filter change at 36K miles. So this fluid had 45K miles on it. AFM was not disabled, but it is now. Seems this is an issue with these transmissions. The shop that rebuilt it said they do at least two a week. Interesting that this sample didn't show more than what it does considering the transmission went bad. Maybe because I didn't drive it once it showed signs of issues??

2016 Suburban ATF.jpg
 
The most common problem is that the converters just absolutely destroy the torque converter clutch, GM programmed them to slip the bejesus out of the clutches I guess for smoother engagement but they wear excessively with the stock tunning, it's generally best to delete AFM and tune the slip tables on the transmission to keep them from burning the clutch up again.
 
That sucks big time. Clean oil will let the trans live much longer than dirty old oil but oil will not keep the parts from breaking.
 
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And yet I'm 322k in and counting on my 2005's 4 speed with nothing but 3 fluid and filter changes only, same story on the 2003 except 2 changes and 208k in. Real shame that 6 spd failed considering it's a 2016 the 6 spd had been around long enough to where there shouldn't have had issues. It was introduced in 2006 and they still have issues. A friend of mine has had 2 rebuilds in his 2012 Silverado in under 110k. Ridiculous. I hope my new 10 speed doesn't blow up. If it does it better do it under warranty at least.
 
This is from our 2016 Suburban with the 6L80E transmission with 81k. It started to whine from the transmission and then we lost all our gears even reverse in just 5 miles from the noise starting. What was weird is that after turning it off and letting it sit it worked again but the whine was still there. Had it rebuilt and the shop said the TC was gone and the pump showed some wear. The fluid was changed out to AMSOIL ATL at 10k miles from new, then I did a pan drop and filter change at 36K miles. So this fluid had 45K miles on it. AFM was not disabled, but it is now. Seems this is an issue with these transmissions. The shop that rebuilt it said they do at least two a week. Interesting that this sample didn't show more than what it does considering the transmission went bad. Maybe because I didn't drive it once it showed signs of issues??

View attachment 99000
Here's 2 used atf lab reports for our 2007 Yokon Denali w/6L80e w/26k and 43k miles on its Dexron6 atf and 174k miles on the trans. At the start of this atf run I stuck a fresh trans filter and torque converter in the vehicle as preventative maintenance while doing an engine rear main seal job so almost 100% of the atf was new (11 qts). The atf that came out was ugly.

Today the tranny has 181k miles and is still working good. We bought the vehicle off a used car lot 4 yrs ago w/no mx history. Based on what I saw inside the engine when I had the rear cover, oil pan, and valve covers off, previous owner(s) were hard on it.

DSCN0021.JPG
 
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