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Highest mileage 8L90?

NWI Denali
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NWI Denali Enthusiast

NWI Denali

Posted
Posted

Just curious who's got 100k or 200k on their 8 speed? Just getting my truck paid off now and at 74k miles, really worrying about the long-term reliability of the 8 speed and wondering if I should trade now while it's still worth something. Had a new valve body at 18k and the new mobil 1 atf at 54k to solve the shuddering. All good so far since  🤞 

m3n00b Enthusiast

m3n00b

Posted
Posted

Subbed.  I only have 43k on mine.  Had a temperature sender replaced and updated fluid to solve shuttering around 30k.    

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Bill Gutman Enthusiast

Bill Gutman

Posted
Posted

Have just over 300,000 my 2018 no problems yet. I just have regular  schedule  matinace  done

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NWI Denali Enthusiast

NWI Denali

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1 hour ago, Bill Gutman said:

Have just over 300,000 my 2018 no problems yet. I just have regular  schedule  matinace  done

That is incredible. I love to hear that.

15 Z71 Senior Enthusiast

15 Z71

Posted
Posted
On 4/3/2023 at 11:50 AM, NWI Denali said:

Just curious who's got 100k or 200k on their 8 speed? Just getting my truck paid off now and at 74k miles, really worrying about the long-term reliability of the 8 speed and wondering if I should trade now while it's still worth something. Had a new valve body at 18k and the new mobil 1 atf at 54k to solve the shuddering. All good so far since  🤞 

I don't have the 8 speed I have the 6 speed mine,it is a 2015. Want to keep mine for another year and worry about the same thing

 I'm at 107,000 now still seems to be fine. (I know your question was about the 8 speed....just getting at I worry about the same thing)

  • Like 1
Cupton Enthusiast

Cupton

Posted
Posted

Just hit 60K the other day in my 2018 Sierra, 8 speed. Ive got another year and its paid off so I'll probably be about the same mileage as you are right now when that time comes. 😉  Other than the usual noises when going in and out of reverse, I dont have any complaints. Shifting is nice and smooth when she's going. 

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NWI Denali Enthusiast

NWI Denali

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1 hour ago, 15 Z71 said:

BTW......which one is has the least problems the 8 or the 6 speed?

The 6 and 10 speeds are both way less troublesome than the 8 speed

DDogg Enthusiast

DDogg

Posted
Posted

I'm at 230 000 km on my 2015.  It's clunky (especially when I put it in reverse) but still doing the job.

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  • 1 month later...
Custom 68 Enthusiast

Custom 68

Posted
Posted (edited)

117k on my 2017. Fluid update change and a temp sensor replaced

Edited by Custom 68
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  • 4 weeks later...
  • 4 months later...
mrctx5000 New Member

mrctx5000

Posted
Posted

Well, I'll chime in here.  On my 2015 8L90 today I passed 350,000 miles .   Its a Yukon XL Denali.  I change the fluid and filter every year. about every 42,000 miles.  Seems to operate well, about 95% of the time.

Thanks.

mrctx.

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  • 4 weeks later...
NWI Denali Enthusiast

NWI Denali

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Posted
On 10/16/2023 at 8:35 PM, mrctx5000 said:

Well, I'll chime in here.  On my 2015 8L90 today I passed 350,000 miles .   Its a Yukon XL Denali.  I change the fluid and filter every year. about every 42,000 miles.  Seems to operate well, about 95% of the time.

Thanks.

mrctx.

Holy crap, I think you win lol

  • Haha 1

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