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2015 Sierra Denali Trans Failure


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Posted

2015 sierra denali 5.3l trans failed at 100,400 miles was flushed at 75k

I had bought 100k extended warranty that ran out 300 miles ago. I am hoping GMPP does the right thing here.

Also I was notified the week previous that my magnaride struts are leaking and wont warranty them. Seems ridiculous to me these thing all failed at 100k

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Posted

6 speed or 8 speed? I think they made both that model year as they slowly phased the 8 speed in. 

Posted

Sorry but:

You put a 100 K miles on it and don't know if its a 6 or 8 speed.

And 1 service in 100 K miles.

 

:)

Posted

I think they slowly introduced the 8 speeds on the 6.2’s in 2014 and 15.


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Posted
8 minutes ago, diyer2 said:

Sorry but:

You put a 100 K miles on it and don't know if its a 6 or 8 speed.

And 1 service in 100 K miles.

 

:)

Sorry everyone is not up to your expertise on the subject.  I was actually pretty damn sure it was a 6 speed. but was leaving myself room to either correct or be corrected if I misspoke.  and no not 1 service in 100k 1 trans flush at 75k.

My vehicle has had plenty of service and recalls if you must know. Heated seat repair, AC condenser repair, Brake recall, steering recall, seatbelt recall, regular oil changes and tire rotation just off the top of my head.

If your not going to be helpful or constructive why post anything? Just to tear someone else down? Maybe you need to revisit your New year's resolution.

Posted
29 minutes ago, Jaychevy81 said:

I think they slowly introduced the 8 speeds on the 6.2’s in 2014 and 15.


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I'm pretty sure all MY 2014 trucks were 6 speed only. MY 2015 was a mix as the 8 speed was phased in.

Posted

In 2015 the 8-sp ONLY came with a 6.2L, not any 5.3L.

Posted

That suck, i been there. Mine went at 120k and i got mine flushed at 88k miles. Im pretty sure the flush caused it.

I wish i had seen that warning before hand. DO NOT GET THEM FLUSHED PEOPLE!

 

What i did was to have it rebuild outside of GM with better parts, knew a guy deal for $2700 cash.

Def fight this with GM, 400 miles outside of warranty is too close to not cover it. 

Dealer may want to give you a discount perhaps but go to GM directly and their social media accounts. If you get it covered, they will just put another GM unit in there.

Posted
2 hours ago, Ozer said:

That suck, i been there. Mine went at 120k and i got mine flushed at 88k miles. Im pretty sure the flush caused it.

I wish i had seen that warning before hand. DO NOT GET THEM FLUSHED PEOPLE!

 

What i did was to have it rebuild outside of GM with better parts, knew a guy deal for $2700 cash.

Def fight this with GM, 400 miles outside of warranty is too close to not cover it. 

Dealer may want to give you a discount perhaps but go to GM directly and their social media accounts. If you get it covered, they will just put another GM unit in there.

First off I want to thank those who defended me. 

I will try every avenue I can with GM to have them cover.

I have 3 friends and a son with Gm trucks 

2014 sierra 130k trans gone

2015 sierra 120k trans gone

2015 sierra denali 100k trans gone (mine)

2015 sierra denali 106k still chugging but owner is concerned

2018 Silverado my son just bought 20k ok for now

all of the above have 5.3L (not sure what trans on these) I have not driven all of these for 100k nor have I counted the number of shifts ? 

Posted
4 hours ago, tjaudet829 said:

2015 sierra denali 5.3l trans failed at 100,400 miles was flushed at 75k

I had bought 100k extended warranty that ran out 300 miles ago. I am hoping GMPP does the right thing here.

Also I was notified the week previous that my magnaride struts are leaking and wont warranty them. Seems ridiculous to me these thing all failed at 100k

Bad news on the transmission, please update on how the warranty company treats you.

It will help others decide if they buy the aftermarket warranty or not.

 

The "really expensive" shocks just seem to be luck of the draw, we lost the rear's n our Tahoe at 60000 miles and the front seem to be just fine.

 

I would check with your dealer on the shocks, they might be able to al least make you some sort of deal on replacements.

Posted
11 minutes ago, tjaudet829 said:

First off I want to thank those who defended me. 

I will try every avenue I can with GM to have them cover.

I have 3 friends and a son with Gm trucks 

2014 sierra 130k trans gone

2015 sierra 120k trans gone

2015 sierra denali 100k trans gone (mine)

2015 sierra denali 106k still chugging but owner is concerned

2018 Silverado my son just bought 20k ok for now

all of the above have 5.3L (not sure what trans on these) I have not driven all of these for 100k nor have I counted the number of shifts ? 

MYC in your RPO codes designates a 6 speed.

 

Let me find the code for the 8 speeds.

Posted
20 minutes ago, JimCost2014 said:

Bad news on the transmission, please update on how the warranty company treats you.

It will help others decide if they buy the aftermarket warranty or not.

 

The "really expensive" shocks just seem to be luck of the draw, we lost the rear's n our Tahoe at 60000 miles and the front seem to be just fine.

 

I would check with your dealer on the shocks, they might be able to al least make you some sort of deal on replacements.

M5U Transmission, 8-speed automatic

M5X Transmission, 8-speed automatic

 

For the 8 speed, maybe someone can chime in why there is two here.

Max towing package possibly?

 

Be patient, you will get some good answers, you just have to sift through the comments of "I have never had one issue with any car I have ever owned" along the way, and the sarcastic remarks about you lack of knowledge of vehicles, which in most cases are not true. 

Posted
15 minutes ago, JimCost2014 said:

Bad news on the transmission, please update on how the warranty company treats you.

It will help others decide if they buy the aftermarket warranty or not.

 

The "really expensive" shocks just seem to be luck of the draw, we lost the rear's n our Tahoe at 60000 miles and the front seem to be just fine.

 

I would check with your dealer on the shocks, they might be able to al least make you some sort of deal on replacements.

the dealer already quoted the new struts at $1900-$2000 don't have the quote in front of me at the moment

I will probably bypass the magnaride and go with an aftermarket rancho or something for about $600 total 

 

Posted
6 minutes ago, tjaudet829 said:

the dealer already quoted the new struts at $1900-$2000 don't have the quote in front of me at the moment

I will probably bypass the magnaride and go with an aftermarket rancho or something for about $600 total 

 

Shop around, slow time of year for everyone, someone may come through with a better deal.

 

It was $1700.00 out the door for the Tahoe.

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