Transmission Slipping, searching for gear 16k miles

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

GreyStone

Full Access Member
Joined
Feb 18, 2020
Posts
896
Reaction score
991
Try driving in Tow/Haul mode - It makes a huge difference in the way my car drives, expecially from a dead stop.
 
OP
OP
S

Sublimize23

TYF Newbie
Joined
Jan 4, 2019
Posts
19
Reaction score
1
Appreciate all the help. I am going to contact Chevy corporate next week, it seems to be getting worse. Drove about an hour highway each way today, 205* on the way up, 200* on the way back. RPM's jumping around even on flat ground cruise control on. Something is definitely wrong
 

BG1988

Full Access Member
Joined
Nov 14, 2018
Posts
2,946
Reaction score
1,344
Unfortunately I believe it is designed that way. You really have to stomp on the gas to down shift and when it does you feel it. I’m guessing to keep RPM low for fuel economy. My 18 Tahoe was like that until I got it tuned. Made trans shifts firm and changed out Dexron VI to AMSOIL. Now it’s smooth as can be.


Sent from my iPhone using Tapatalk
I suggest that you
check the IAT MAF and map sensors to make sure those are operating correctly..
these can cause funky issues with the throttle and transmission

!! check and make sure when you shift it from Reverse gear to Drive you give it at lest 2 seconds.. mine was shuttering pretty bad tell i started doing that, and no shuttering (violent shaking) so far from it. (when shutter conditions are met)..

i.e shift from 1 to 2 second gear at low speeds in parking lot with light throttle or hovering about 9-11mph...
 
Last edited:

sealandsky

Full Access Member
Joined
Jun 28, 2019
Posts
510
Reaction score
251
Location
Minneapolis, MN
Sounds like an issue that you will need to resolve with the dealer under your warranty. It's definitely not normal.
 

RB_Trucker

Full Access Member
Joined
Aug 26, 2015
Posts
147
Reaction score
194
Location
Redondo Beach
I suggest that you
check the IAT MAF and map sensors to make sure those are operating correctly..
these can cause funky issues with the throttle and transmission

!! check and make sure when you shift it from Reverse gear to Drive you give it at lest 2 seconds.. mine was shuttering pretty bad tell i started doing that, and no shuttering (violent shaking) so far from it. (when shutter conditions are met)..

i.e shift from 1 to 2 second gear at low speeds in parking lot with light throttle or hovering about 9-11mph...

My 2019 4 x 4 LT suburban does the same thing that yours does. I have a black bear tune for the transmission and engine and it only does it when I’m in normal drive mode and if I put it in tow haul or manual it does shift normal. It’s a 1-2 shift flare at 10-15 mph 1/4 throttle and below.
 

BG1988

Full Access Member
Joined
Nov 14, 2018
Posts
2,946
Reaction score
1,344
My 2019 4 x 4 LT suburban does the same thing that yours does. I have a black bear tune for the transmission and engine and it only does it when I’m in normal drive mode and if I put it in tow haul or manual it does shift normal. It’s a 1-2 shift flare at 10-15 mph 1/4 throttle and below.
it was a clogged air filter that was causing it the engine was almost pulling a full vacuum (not a negative vacuum but very little air entering the engine)on the intake tube that is why I was getting P0069 doh so the engine was getting air starved this whole time causing my shuttering i put a new filter all is good again the OP should try a new air filter first


the filter looked clean but was clogged with very fine powered dirt.. there was also some stuff on the bottom of the air box(fine dirt an a few bugs)


so it was dropping to 15kPa (2.2 psi) or less (very little air available at 2.2PSI)

while normal idle is 50-70(kPa) 7.3 to 10.1


average vac is 35-45kPa(5.1-6.52PSI) while driving on the road

normal ATM is 14.4 psi at sea level (im at 2200 feet so it's 92kPA or 13.4PSI) with Key on


when the MAP was dropping you can see the MAF reading intake drop as well when it does it
 
Last edited:

Tiredmechanic23

Full Access Member
Joined
Sep 19, 2019
Posts
192
Reaction score
126
Dunno about the 2019s but the 6speeds were known for shit torque converters. My converter failed at 90k miles and took out my trans with no prior signs of issues. Just suddenly on a drive had it flare a couple times then all neutrals past 2nd.

Dunno if it extends to the 2019s but I believe there was a TSB about it. New build with a new converter and a black bear tune and all is much better.
 
OP
OP
S

Sublimize23

TYF Newbie
Joined
Jan 4, 2019
Posts
19
Reaction score
1
I guess final update: I've decided to trade the car in. I can't own a vehicle with such questionable reliability. GM corporate didn't/wouldn't do the one thing I asked for, which was to provide me with a loaner or rental while they figured out my truck, that's all. They said I should drop it off, rent my own car, and submit for reimbursement, making sure to tell me that it wasn't guaranteed. That's just plain unacceptable to me. It isn't about the money, rental cars are super cheap right now, it's the principle.

The 2 dealerships here refused me a loaner when I called and asked before I went, so that was that.

I'm getting something else, I don't think I'll ever own another GM product.

0% APR over at Lexus right now due to covid if anyone is interested.
 

Forum statistics

Threads
129,209
Posts
1,812,162
Members
92,308
Latest member
madmax442

Latest posts

Top