Every so often 1st gear slips

[Just00Jake]

I have a 2013 Chevy Tahoe LS., When I'll be at a dead STOP, at a traffic light etc. I'll ease off the break pedal and start accelerating and my transmission slips and then by the time I realize it's happening my RPMs are a bit higher than desired to be shifting into first gear and I get the jolt forward. I have all of my fluids at the proper levels and the vehicle is well maintained, and I tried a transmission treatment but it didn't seem to fix it. I do have an OBD2 scanner and I've only once gotten a trouble code for shift solenoid for 1st gear but cleared it, and I too never see it again. If it were my '05 LT I'd replace the 2 shift solenoids like I've done in the past, but I but this has a 6L-80 transmission and it doesn't look as simple as that. I Any suggestions?

 

[Geotrash]

I have a 2013 Chevy Tahoe LS., When I'll be at a dead STOP, at a traffic light etc. I'll ease off the break pedal and start accelerating and my transmission slips and then by the time I realize it's happening my RPMs are a bit higher than desired to be shifting into first gear and I get the jolt forward. I have all of my fluids at the proper levels and the vehicle is well maintained, and I tried a transmission treatment but it didn't seem to fix it. I do have an OBD2 scanner and I've only once gotten a trouble code for shift solenoid for 1st gear but cleared it, and I too never see it again. If it were my '05 LT I'd replace the 2 shift solenoids like I've done in the past, but I but this has a 6L-80 transmission and it doesn't look as simple as that. I Any suggestions?

Is it truly a slip or is it a delayed upshift?

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

I cannot personally help you with your question; however, other members on this Forum that are much more knowledgeable than me are chiming in.

 

[Dustin Jackson]

To be clear, when trying to drive from a stop the RPMs will increase without the vehicle moving and then it kind of bangs harshly into 1st gear? And then you start rolling?

I recommend not clearing a code unless you did something to fix it, you should move forward with that code in mind.

 

[Just00Jake]

Is it truly a slip or is it a delayed upshift?

I guess it could be a delayed up shift

 

[Geotrash]

I guess it could be a delayed up shift

The 6L80 valvebody is a common source of slipping and delayed upshifts. There are check balls in the system that wear down and start sticking, and bore wear in the solenoids and pressure regulator can cause these issues as well. Sonnax and Transgo make kits that include replacement parts for the most common valvebody issues, and some folks here have had great success with rebuilding their valvebodies on the kitchen table with one of these kits.

 

[swathdiver]

Might be time to rebuild the TECHM.

 

[Just00Jake]

The 6L80 valvebody is a common source of slipping and delayed upshifts. There are check balls in the system that wear down and start sticking, and bore wear in the solenoids and pressure regulator can cause these issues as well. Sonnax and Transgo make kits that include replacement parts for the most common valvebody issues, and some folks here have had great success with rebuilding their valvebodies on the kitchen table with one of these kits.

Thank you for the advice. I am used to the old 4L60, this thing looked a bit intimidating at first glance. Kitchen table huh? I'll give that a shot. I Thank you

 

[skpyle]

Hello Just00Jake,

Take a look at my thread here:

https://www.tahoeyukonforum.com/thr...-flush-in-2013-escalade-esv-pic-heavy.130110/


It is far more in depth than you are going, but it has good info on rebuilding the TECHM.

Good Luck!

 

[gpracer1]

My brothers 12 is doing the exact same thing. Started with door locks on and off, electrical flickering on and off, and fixed with positive battery fuse replacement and cleaning corroded positive at the fuse box. That is fixed ,he still however still has the intermittent start from a light, revs then bump into gear.