which 10th generation years have no transmission issues? 4L60E versus 6L80E

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dictum

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Want to get a 2007-2014 Suburuban, meaning a 10th generation.
But I hear of ongoing issues with the 6L80E transmission -
Torque Converter Clutch issues which generally fills the unit with Aluminum and Steel debris before it can be caught & repaired in time.
Requiring a full rebuild & replacing the trans coolers. The 11th gen 6L80E is even more prone to this failure because changes to the calibration.

Should I stay with early gen 10th or even gen 9?

My 2008 Tahoe with 5.3L/4L60E made it to 257K on everything original thus far.
 

LordWayback

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6l80e : electrical demons all day sometimes mechanical better on gas 4l60e ; mechanical demons worse on gas
You just have to pick your poison the 6L80’s have slightly better mileage but the 4L60’s just have mechanical issues as far as I’ve heard besides the programming 4L’s just need a good rebuild and they’re great for another 200k.
 

LordWayback

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No 9th/10th or really any gen suburban has a bulletproof automatic transmission they’re usually under-built for these heavy trucks if you wanted a unkillable trans you need to go back to 6/7th gen transition and get a manual but most of those trucks are rusted out junkers and bad on gas/no creature comforts anywhere close to 9th gen+. And not what you want the best you can do is early fluid changes and not flooring every stop sign.
 

swathdiver

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Want to get a 2007-2014 Suburuban, meaning a 10th generation.
But I hear of ongoing issues with the 6L80E transmission -
Torque Converter Clutch issues which generally fills the unit with Aluminum and Steel debris before it can be caught & repaired in time.
Requiring a full rebuild & replacing the trans coolers. The 11th gen 6L80E is even more prone to this failure because changes to the calibration.

Should I stay with early gen 10th or even gen 9?

My 2008 Tahoe with 5.3L/4L60E made it to 257K on everything original thus far.

The 6L80, no E, is an excellent transmission and lasts a very long time when taken care of. At around 165K the TECHM solenoids need to be rebuilt on units that were not serviced at all or sometime after 100K miles, generally speaking. Torque converter failure happens more often with the K2s, not the 900s.

The real advantage of the 6-speed over the 4-speed is not fuel efficiency, it's gearing and towing prowess. What increased the gas mileage on the 2010+ over the 2007-2009 cars was the addition of Variable Valve Timing on the 5.3 engines.

2012-2014 are your ultimate years with all the improvements.

It is not unusual to see 6L80s and 6L90s hit 300K and 400K plus miles when the severe service schedule is followed.
 

intheburbs

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Frequently changing the fluid is key.
I have a 4L60 with 310k miles. I abused it enough from towing heavy that it's wearing rear axle #4.
My 6L90 has 210k and still runs/shifts perfectly. It gets flushed every 50k, or less if I'm towing my 8600-lb behemoth frequently or up to silly altitude (10k+ elevations).

ETA: Full flush, 16 quarts. Not just a pan drop and 4-5 quarts.
 
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Geotrash

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Want to get a 2007-2014 Suburuban, meaning a 10th generation.
But I hear of ongoing issues with the 6L80E transmission -
Torque Converter Clutch issues which generally fills the unit with Aluminum and Steel debris before it can be caught & repaired in time.
Requiring a full rebuild & replacing the trans coolers. The 11th gen 6L80E is even more prone to this failure because changes to the calibration.

Should I stay with early gen 10th or even gen 9?

My 2008 Tahoe with 5.3L/4L60E made it to 257K on everything original thus far.
I have 224K on the original 6L80 in my 2007 but did upgrade the torque converter in my 2012 with 132K because I tow heavy with it and want it to remain reliable. Total cost of the new TC with R&R labor and a new rear main seal was $1400. Not worth agonizing over, in my opinion. That's less than the cost of the rear entertainment system on a new one :)
 
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dictum

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What about the 2500 series Suburbans of that vintage? Do they come with a heavier-duty transmission on top of all the suspension differences between 1500 and 2500 Burbs?

What about the 6.0L engine in the 2500-series? Does it get 13MPG max? And not recommended as a daily driver?
 

wjburken

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What about the 2500 series Suburbans of that vintage? Do they come with a heavier-duty transmission on top of all the suspension differences between 1500 and 2500 Burbs?

What about the 6.0L engine in the 2500-series? Does it get 13MPG max? And not recommended as a daily driver?
If I’m not mistaken, the 2500’s of that generation came with the 6L90 transmission so yes, it’s heavier duty than the 1500’s.
 

Doubeleive

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What about the 2500 series Suburbans of that vintage? Do they come with a heavier-duty transmission on top of all the suspension differences between 1500 and 2500 Burbs?

What about the 6.0L engine in the 2500-series? Does it get 13MPG max? And not recommended as a daily driver?
the bottom line is if you drive like a normal sane person you might never have transmission issue's even with the lowly 4l60. If you push the big pedal hard there is no such thing as a trouble free transmission it just comes with the territory.
 

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