Not sure what the issue is yet according to the dealer. For sure, there is a shutter and vibration when accelerating to 45 mph or greater and maintaining. First step before I can get my extended warranty to work is to do a transmission fluid flush and replace with a special oil. Dealer says this is a common issue with 2018 Colorado. However, replacing fluid does not fall under extended warranty, so I am out of pocket supposedly about $800. They will try that first and if it’s something else, supposedly then the extended warranty will kick in. I called the extended warranty and they said they will not reimburse me if the replacement of the fluids did not fix the issue and if it was mechanical. It doesn’t make sense. If this is a known issue, where is the class action lawsuit?

Took the vehicle to Chevy in 2021 for a shutter it had 56K on the odometer, they replaced the torque converter. The problem started again after it was out of warranty in Nov 2023 with 77k on it. took to dealer and they informed me that the transmission was shot and I had to eat the cost due to being out of warranty..$.7808 ..this seems to me to be considered a reoccurring problem and they should replace it on GMs dime.

On the bright side GM gave me 1500 assistance which the dealer told me If a waited for GM to send that money it would take 6 weeks to get it back with a 12 /12k warranty. Now if I pay the 7808 it will get the car back in a week and a half with a 36 10000mile warranty, the dealership will put in for my 1500 assistance to be sent to me. My decision was a no brainer I went with the 3yr 10000 mile deal ...I am a very unhappy Colorado owner.

Started to notice the Shudder about 6 weeks ago. I had the oil changed and tires rotated, thinking that would fix the issue. I mentioned it to my mechanic but of course the truck was perfect while he tested it. Over the last week the shuddering got worse and I took it to the dealer. They want to charge me $8100 to replace the transmission. The technician seemed annoyed when I told him what I found online, and what recommendations are. He told me the warranty was expired and would not acknowledge that it is a known issue. When I pushed for the flush and change of fluid he then said the transmission was slipping and the flush wont fix it. I'm currently looking to other dealers to do the flush and change the fluid to Amsoil ATL.

How do I find out if I qualify to join the class action suit? What about the buyback program?

2018 Colorado with 62,000 miles. I never thought much of the issue, just thought it was bumpy roads. I received a letter from a law firm stating the problem with the Colorados. Went to Randy Marion Chevy in Statesville NC where my truck has always been serviced and mentioned it, and they checked it out and said it needs a fluid change to fix it. They told me it would be $1250 to fix. Now my truck was there a couple of months before for normal service and of course no one ever mentioned anything about a trans issue with these trucks - and of course the multipoint vehicle check states no issues. Amazing how after the warranty expires, the problem shows up! Getting it fixed I hope tomorrow and I'll deal with legal action to get my money back from this known issue that GM keeps blowing off!

The issue started around the first week in August. Had ~69,000 miles on it at the time. I had just put new tires on. Thought the tires might be the issue so I took it back and had them all re-balanced. The problem persisted on the way home. I would feel a vibration during acceleration after 20 MPH. It felt like driving over rumble strips. It would not start vibrating until after the vehicle was warmed up. Had to drive 8 to 10 miles first.

I paid for an extended warranty. Even with this, the $780 repair was no covered. I bought the vehicle used with 16K on it. The dealer found the service bulletin and flushed the transmission. Picking it up later today.

I have been a die hard GM fan for over 30 years. This put me over the edge. Won't buy a Chevy again.

So... is there a class action law suit? Why is this not GM's responsibility?

If flushing the transmission clears the problem, there is either debris in the fluid or the fluid has broken down and doesn't provide lubrication like it should. It's not my fault. I maintain my vehicles very well.

I have seen many other threads on this topic from other websites. Seems to be a common theme.

I have a new 2018 Chevy Colorado v.6 crew cab z71 with only 6595 miles on it and it picked up a shudder running down smooth pavement at highway speeds. I was showing my girlfriend who said it feels like running down rumble strips on the shoulder. I called dealership in Pooler Georgia and the service manager was not available. The lady seemed like she never heard of the issue. Funny, I found it right away online and it sounds like it's been an issue since 2015.

Well, I just got off the phone with the service manager and he advised me that because of what I described that my truck will have the fluid changed out next Tuesday. When I asked why it had not been corrected by GM, he said it had. My truck was made in 2017 before the fix and he said in 99% of the trucks that the flush fixes it. My luck has never been that good - when someone tells me 99%, I am the guy that is the other 1%. So I guess until next Tuesday, I have the Chevy shakes as they call them. A lot of posts say the flush does not work - I guess we shall see.

Long story short, I purchased a 2018 Colorado Z71 with the 3.6 V6 engine. Love the truck, and everything is great except for this transmission issue. Back in late 2018 I noticed the shudder issue so I took it to my local dealership. They knew about it, and they said they were aware of the problem and will order parts. Truck only had about 9100 miles. Parts came in and about 3 days later, I got my truck back.

All was great until last week where I noticed the shudder issue coming back. I have also noticed now 3 times that when I start it, the transmission acts like it jumped in gear and made a bang noise. The truck just turned 17K miles. I'm really disappointed with Chevrolet. First brand new vehicle I purchased in my life. All my other trucks have been used and all of them have been S10 and never have I had any issues with them. Took it to the dealership on Saturday and I will be calling them on Monday to setup an appointment this week.

The infamous COLORADO SHUDDER!!!

Started when vehicle was less than a year old... I brought it in around 40,000 and was told it needed a transmission fluid exchange and ref bulletin # 18-NA-355. I've since had it in 2 more times (at least) and have been told nothing is wrong with it... and just the other day a different dealer replaced the fluid again with new & improved fluid and low and behold about 50 miles later its doing it again! The Colorado shudder is back! This is getting very old and worrisome. I would be interested in a class-action if there is one out there. Chevy/GM knows its happening... I'll never buy another Chevy/GM product!

This vehicle has been babied and not hardly worked at all. I had the transmission flushed as recommended and the shop owner said the transmission had an excessive amount of metal shavings in it. I have an extended warranty on the vehicle through 100,000 miles, but the issuing company denied the claim and said it was just a flush and is not covered. I don't even know if the vehicle is now fixed as I have to drive it a few hundred miles to see. If it does the shuddering again, I have to have it flushed again at my expense. This is where I will decide if I keep it or not.

Update from Nov 3, 2021: Had transmission flushed. They noticed abnormal amount of metal filings. These were said to be mostly due to too close tolerances, so parts had some interference. So far the problem has been alleviated but I am out the repair bill.

I see several similar posts regarding the transmission shudder. My dealership was accommodating but like several others, I still have concerns. I love this vehicle and have invested in many after market options. I am also over 75 and expected this to be my forever vehicle but I have concerns for its future. I purchased it used with 13,000 miles and the issue wasn't confirmed till 29,000 miles when the trans was flushed. That fixed the shudder but I have several other different concerns. When I slow to stop for a red light that turns green when I get there, and accelerate, occasionally I get nothing and then a lurch. I also had it clunk when I start it unexplainably several times. I regularly feel a throbbing similar to a bulged tire that is not always on the same road but its very subtle and unless you are listening for it, its not obvious. It will do the ripples on a cup of coffee in the cup holder.

ALSO, I'm wondering when others had their trans flush, if the trans fluid info screen reset the mileage. When they flushed mine, the mileage remained the same. First I was told they would reset it and then they said they don't do it??? SO... now of course I am wondering if it had been done once or more already when I purchased it. How did your dealership handle this?

We drive from Michigan to FL each year and while my dealership is understanding, I don't want to be stuck in the mountains or in a strange town with no reservations at a dealership that may be not as accommodating...

Took my truck in to service concerned about the vibration. They did a 4 wheel alignment and tire balance, and wanted to do a transmission flush. Told them I would come back for the flush because I had to go to work. I have it scheduled for Monday 21st October. So at home I started the web search on 2018 Colorado vibrations. Much to my surprise there is a long list of others with the same problem. The more I read about it and thought about it I got a little annoyed about the situation. If Chevy knew about the problem, why didn't they fix it before I bought the truck. Now I have to take time off of work again to flush the transmission and who knows how long that will last? I'm very disappointed and thinking I should have waited for the new Rangers to come out.

Well, let’s see. I was sold a truck with the dealership knowing the a8 tranny has had issues. The service dept knew and so did management - they had to. They were getting the how-to-repair memos since 2015. There was no warning about the issue before purchasing my 2018 truck and from what I have read online, there’s no permanent fix. They’re still trying to figure it out. So I had to lose a day's work of overtime taking the truck in.

It’s unsafe to drive in my opinion. I almost wrecked twice. I arrived there at 730 am, asked for a vehicle to get around in, then asked how long. The man said 2.5 hours. I said okay, I can wait well and 4.5 hours later, they call saying that I’m ready to go. They flushed the tranny per work order from GM. For this is the first step and cheapest to fix. Now I'm wet from walking in the rain, hungry and ready to just go get my truck back. Well, it has not been detailed or vacuumed out. I can't complain too much about that but knowing a new truck with only 7 k miles on it almost got in a wreck twice is very dangerous to drive and I was feeling unsafe driving it.

I was told they have the autos in there all the time for the same fix. Mine was the first of four for the same issue for that day I took it in. So the only reason I gave such a high score is because I truly don’t think the young lady who sold me the truck had a clue about this issue. I'm scared if what I read is true and this is only a short time repair band-aid. I got lucky the first two times when I almost wrecked because I did not have any vehicles around me when I crossed the center lane from this issue.

GM really disappointed me on this new auto. It's like when I drive, when is it going to come back, how many miles and where will I be when will it get in in a wreck.

PS The flush has been done - we’ll see how long this band-aid holds.