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Posted

I have 15 sierra 5.3l 6 speed 72,000miles and noticed my rpm needle jumping a couple 100 rpm the coming right back down again and keeps doing so . Does this only in 5th gear. Took to my mechanic he hooked it up to computer and nothing came up wrong. Had him do Trans service couple metal shavings were found in the pan and good amount of fine metal dust. Truck is still acting the same if not worse. Mech recommended transmission replacement. I'm at a loss. Any info would be appreciated. Thanks all

Posted
5 hours ago, Shawn Hixenbaugh said:

I have 15 sierra 5.3l 6 speed 72,000miles and noticed my rpm needle jumping a couple 100 rpm the coming right back down again and keeps doing so . Does this only in 5th gear. Took to my mechanic he hooked it up to computer and nothing came up wrong. Had him do Trans service couple metal shavings were found in the pan and good amount of fine metal dust. Truck is still acting the same if not worse. Mech recommended transmission replacement. I'm at a loss. Any info would be appreciated. Thanks all

Welcome to the site.

 

Any vibrations? Does your mechanic have the ability to shut off the torque converter while driving? Easy way to tell if it is going out, very common problem with the 6 speeds at your mileage.

Posted

You may have seen my posts in other related topics but here is what mine did..

On my 2014 i had experienced the same symptoms, shudder in low RPM, especially going up an incline. I thought it was a misfire and after getting that ruled out i took it to the dealer and they confirmed that it was the TQ. They pulled the pan out and chunks of metal was stuck on the magnet. They said new trans is needed, $5300 out the door.

I got the truck towed to a local trans shop and got it rebuilt with better parts and some mods for $2700 cash. 

 

If you are still under warranty def get it to the dealer for a replacement. 

Posted
On 4/17/2020 at 9:05 AM, Ozer said:

You may have seen my posts in other related topics but here is what mine did..

On my 2014 i had experienced the same symptoms, shudder in low RPM, especially going up an incline. I thought it was a misfire and after getting that ruled out i took it to the dealer and they confirmed that it was the TQ. They pulled the pan out and chunks of metal was stuck on the magnet. They said new trans is needed, $5300 out the door.

I got the truck towed to a local trans shop and got it rebuilt with better parts and some mods for $2700 cash. 

 

If you are still under warranty def get it to the dealer for a replacement. 


Hey there I’m currently having all the same issues with my 17 z71 90,000 miles. Local trans shop said rebuild would be $3,000 with upgraded torque convertor. Curious what was the warranty on the $5300 installation at the dealer. I’ve noticed the fluid looks brown and notice some fine metal shavings on the dip stick. Just baffled that such a new truck is commonly having early trans issues. 

  • 4 weeks later...
Posted

My truck was experiencing pain, itching, and small sores one it's fuel line, so I contacted DR. OSO.

CURED! Truck runs like new again.

  • 8 months later...
  • 1 month later...
Posted

Seems to be a common problem. My torque converter just failed and took out the transmission. Is there an appropriate place to report these kind of issues?  I always hear "there has been thousands of complaints of problem xxxx" but don't know where to report the issue. I imagine most pre-mature failures go unreported. NHSTA has a complaint section but that looks like safety related only. Just wondering if there is another agency that collects this kind of data.

  • 10 months later...
Posted
On 4/16/2020 at 6:14 PM, Shawn Hixenbaugh said:

I have 15 sierra 5.3l 6 speed 72,000miles and noticed my rpm needle jumping a couple 100 rpm the coming right back down again and keeps doing so . Does this only in 5th gear. Took to my mechanic he hooked it up to computer and nothing came up wrong. Had him do Trans service couple metal shavings were found in the pan and good amount of fine metal dust. Truck is still acting the same if not worse. Mech recommended transmission replacement. I'm at a loss. Any info would be appreciated. Thanks all

 

I am having this exact issue. At cruise 40mph was getting small blips of 100 to 200 rpm with minor shuddering. Assumed it was bad fuel (just filled up) or bad plug wire. Then about 2 hours later at a intersection would not move in D or R. After a min i got it to limp into a parking lot. Towed to shop no CEL or anything obvious. After talking to my tuner (Diablew tune) and pointed me to a convertor i called the shop who is now going to drop the pan and look ($175 fee if not.......) after sitting they said its running fine now. But blaming my tune thats been in for over a year

Posted

Shame on GM, they built a shabby 8-speed transmission/torque converter, and continue for years knowing that a Large % of them are going to Fail at or shortly after, the warranty is over.  

If GM actually cared about customer service they would recall ALL these 8-speed transmissions, inspect and replace with Quality Product.

 

Just my 2 cents-

Posted

the transmissions are engineered to fail by GM due to epa enviromental mandates by the Feds.

 

they dont want your in your truck more than 80,000 miles , buy a new one is the direction they are pushing you.

 

the pre-failure fixes are well know on this site use the search bar, as the same failure points directed at the 6 speed are implimented on the newer transmissions

 

 

Posted
On 2/21/2022 at 10:24 AM, afireinside7444 said:

 

I am having this exact issue. At cruise 40mph was getting small blips of 100 to 200 rpm with minor shuddering. Assumed it was bad fuel (just filled up) or bad plug wire. Then about 2 hours later at a intersection would not move in D or R. After a min i got it to limp into a parking lot. Towed to shop no CEL or anything obvious. After talking to my tuner (Diablew tune) and pointed me to a convertor i called the shop who is now going to drop the pan and look ($175 fee if not.......) after sitting they said its running fine now. But blaming my tune thats been in for over a year

your tuner doesnt know what he's doing otherwise he would have corrected the issue in the software. and told you what parts need to be upgraded

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