I first noticed the vibration around town, when accelarating between 30-50 mph. I took it on a long trip and noticed it under slower accelerations and especially between 1700 and 1900 rpms when the transmission shifted down while going uphill. I worked for GM for 31 years and simply cannot believe that they have not stepped up to this problem as many owners are complaining. What happens when the warranty runs out and a transmission costs the consumer? This is how market share is lost. This is an otherwise awesome truck, for now.

Update from May 17, 2019: A local dealership changed out the transmission fluid 4 days ago. So far the problem has gone away.

As soon as I mentioned the problem, the service advisor said they needed to change the transmission fluid...not test drive or anything. That didn't fix the problem.

Then they changed the torque convertor. Still didn't fix the problem.

They changed the fluid again, with a different fluid this time. My truck is worse than ever now.

Spoke to Thomas at Chevrolet customer assistance department. He suggested I take the truck back to the dealer and trade it for something else! He's gotta be crazy to think I'm going to go back to the same dealer that has been letting me down for over a year and take a huge hit on a trade, especially now that I know GM is aware of the problems with this transmission and they keep selling them anyway. They should be ashamed of themselves for doing this to people.

Dec2018: dealer replaced torque converter, triple flush.

Shudder came back less than a thousand miles, waited until mid February for new fluid.

Feb 2019: truck flushed with new fluid, truck never felt right.

March 2019: shudder returned, dealer acknowledged, GM won't fix

Update from Jul 31, 2019: May 2019: Dealer replaced transmission, transmission still shudders.

July 2019: Dealer flushed transmission, truck still shuddering

July 2019: Start buyback process

Same issue as previously noted by others. Shuddering under light acceleration between 30-65 mph. The only response from my dealer when I reported it was, "Call back in about a week and we might have a fix." In the meantime I don't know if my transmission is coming apart inside or not. At a minimum I think the drivetrain warranty should be extended once a fix is found. Ideally I would like the entire drivetrain replaced. Especially after reading about metal filings found in replaced torque converters. I mean, what's the inside of my engine look like after running with this shuddering?

Shudder/Vibration easily felt in steering column about a week ago, has gotten worse and more often. My dealer has been great getting me in a loaner car, so no complaints there. They said I needed to replace the torque converter, so that's what is happening as of today. My main concern was 2 things: 1. My truck only has 2500 miles on it, so it's essentially new. Is this a blessing in disguise, or is it the start of recurring issues? I hope not, because I really love this truck. 2. The tech who signed me in mentioned it may be the transmission fluid they'd used originally, (or the torque converter, which it ended up being). My concern is wondering what they used, why that could cause shudder, vibration, any "long term effects" for the transmission? I understand that may be a different issue, but I found it interesting the tech volunteered this info as if it's a fairly frequently occurring problem for the 2018 Colorado with the 8 speed automatic. In any event, I assume they'll do a transmission flush anyway along with replacing the torque converter.

Yes. it's true! At +/- 1,400 miles, I first experienced a shuddering that could make the beverage in my cup sitting in the cup holder on the right side of the transmission shifting lever form foam. Oh dang, but road repairs in some parts of Texas appear to be irregularly semi-scheduled in a non reoccurring manner on a random basis. My weekly trips along the same road were the only time I was noticing the shudder, so I just chalked it up to bumpy secondary country roads.. And then it happened!

Cruising down the interstate not on cruise control doing around 73 MPH on a flat straight section, I lightly accelerated to kick it up a bit to set the cruise control.. Foam forming in my beverage may have occurred, but I was too preoccupied attempting to see how many pine logs I had just run over to cause the worse jerking experienced yet. I once had a utility trailer built without any suspension using springs, or shocks.. Seeing it jump off the ground and come down with a bang was an experience, and that's what it felt like this time.

The shuddering was soon occurring often and the speed didn't seem to be the major factor, Just trying to lightly accelerate while cruising along in a higher gear seemed to be the cause and I was soon good at intentionally replicating the action at will.. I searched the internet to see if this had been a reported problem or one subject to a Chevrolet recall when I happened upon this site. I have thoroughly enjoyed reading of the same problem occurring with others and was stimulated to finally contact my Chevy Dealer yesterday with only 2700 miles on my truck!

I made a trip to visit the Service Manager personally and was glad that I did. He was very knowledgeable of these situations and explained a sequential approach to effect a proper solution.. His plan of attack sounds very similar to what I have read aout so far.--Flush the transmission, check fluid flows, and probably replace the torque converter. If it checks out OK there, I'll drive it for a few hundred miles to see if it was "fixed" or not. If NOT, a prescription for surgery and a transmission replacement may be necessitated.

My truck will be dropped of tomorrow and updates will be forthcoming in case anyone would like to send a get well card!.

This is the 3rd time my truck is in the shop for same problem. 1st time I was told it was the oxygen sensor and that it was fixed. Got the truck back and same problem within 4 days. 2nd time I was told it was the engine struts. They needed to remove the top of the engine to replace. Service manager requested he drive it home with computer hooked to car. He lives 40 miles away roughly. Next day was called and told they need the car til end of the week to fix. Computer showed it was carbon build up. They changed the engine, transmission oils and filters, also blew out all the carbon build up in the engine which will solve the problem. ( all this for a truck with 5k mile) I was told to drive the truck for 200 miles so the engine can get used to the new oils. WTF? Within 50 Miles the problem came back worse and was notified twice by email thru OnStar of a detected in the transmission. 3rd time I brought into the dealer, they have had it for 4 days so far and just heard they are replacing the fuel pump, it's leaking fuel into the oil...lol

KEEP YOUR FINGERS CROSSED THIS IS IT

I bought the New Chevy Colorado and was happy with it. I started having the shake in the truck so I mentioned it to the local Chevy dealer and they said they had not heard of any complaints. The problem just kept getting worse although they said they had not known of any problems. Finally I called and asked if they had a recall on the truck and they said "No". I said well I have a problem, my truck will shake you out of the seat when accelerating. They asked at what speed? I said it starts at about 35 miles and hour and only get worse the faster you try to go. What made me mad was they said Chevy was not issuing a recall but they would repair the truck if I wanted to bring it in. Chevy knows they have a problem but rather than recalling them to repair the problem they want the consumers to keep the truck and GM hoping it gets out of warranty before it shows up. Mine got so bad it would shake the dash so bad it was tearing it apart. I took mine in last Friday and they said it would be ready sometime next week. Thank goodness I don't need to go anywhere. Being 62 years old I don't walk as fast as I did when I was younger.