I am having a problem with the Hydra-Matic 6L50 six-speed automatic transmission in my 2017 Chevrolet Colorado with the Baby Duramax engine. The problem started to occur occasionally and now is increasing in frequency. I am wondering if other Colorado and Canyon diesel owners are experiencing the same thing and if there is a recall or other solution to the problem.
I first want to say that I have looked everywhere under the hood or looking at the transmission itself and I can not find a dipstick or a viewing window for measuring transmission fluid levels. There also does not appear to be anywhere under the hood for topping up transmission fluid. This is very frustrating as the problem feels like the transmission is low on fluid.
On to the problem itself... This seems to only happen when you want to go forward with the truck from a dead stop. The problem has not appeared when I am in reverse, only when the engine is in drive with the intention of moving forward. The transmission seems to become disconnected from the engine and the engine will rev freely like it is bolted to a manual transmission and you are pressing down on the clutch or are in neutral…. with the result being no forward motion of the vehicle. This can be very hazardous when you have partially rolled into an intersection and there are other drivers trying to get around you. Then, after a short period of time that can be anywhere from 1 to 20 seconds the transmission will engage with the engine very abruptly with a “thunk” sound and the vehicle jerking forward a foot or so. I try to not rev the engine when this problem occurs as it seems like the transmission achieves fluid lock-up suddenly and the result is the transmission parts get hammered.
The engine is running fine, and I am having no issues with it. This vehicle is very low mileage and only has 71,000 KM, (less than 45,000 miles), rolled up on it. I do not abuse my vehicles and this Colorado in particular has been treated very gently, so this problem where it feels like someone has burned out the transmission is very perplexing.
I AM HAVING PROBLEMS WITH THE 6L50 SIX SPEED AUTOMATIC TRANSMISSION IN MY 2017 CHEVROLET COLORADO DIESEL.
I am having a problem with the Hydra-Matic 6L50 six-speed automatic transmission in my 2017 Chevrolet Colorado with the Baby Duramax engine. The problem started to occur occasionally and now is increasing in frequency. I am wondering if other Colorado and Canyon diesel owners are experiencing the same thing and if there is a recall or other solution to the problem.
I first want to say that I have looked everywhere under the hood or looking at the transmission itself and I can not find a dipstick or a viewing window for measuring transmission fluid levels. There also does not appear to be anywhere under the hood for topping up transmission fluid. This is very frustrating as the problem feels like the transmission is low on fluid.
On to the problem itself... This seems to only happen when you want to go forward with the truck from a dead stop. The problem has not appeared when I am in reverse, only when the engine is in drive with the intention of moving forward. The transmission seems to become disconnected from the engine and the engine will rev freely like it is bolted to a manual transmission and you are pressing down on the clutch or are in neutral…. with the result being no forward motion of the vehicle. This can be very hazardous when you have partially rolled into an intersection and there are other drivers trying to get around you. Then, after a short period of time that can be anywhere from 1 to 20 seconds the transmission will engage with the engine very abruptly with a “thunk” sound and the vehicle jerking forward a foot or so. I try to not rev the engine when this problem occurs as it seems like the transmission achieves fluid lock-up suddenly and the result is the transmission parts get hammered.
The engine is running fine, and I am having no issues with it. This vehicle is very low mileage and only has 71,000 KM, (less than 45,000 miles), rolled up on it. I do not abuse my vehicles and this Colorado in particular has been treated very gently, so this problem where it feels like someone has burned out the transmission is very perplexing.
I first want to say that I have looked everywhere under the hood or looking at the transmission itself and I can not find a dipstick or a viewing window for measuring transmission fluid levels. There also does not appear to be anywhere under the hood for topping up transmission fluid. This is very frustrating as the problem feels like the transmission is low on fluid.
On to the problem itself... This seems to only happen when you want to go forward with the truck from a dead stop. The problem has not appeared when I am in reverse, only when the engine is in drive with the intention of moving forward. The transmission seems to become disconnected from the engine and the engine will rev freely like it is bolted to a manual transmission and you are pressing down on the clutch or are in neutral…. with the result being no forward motion of the vehicle. This can be very hazardous when you have partially rolled into an intersection and there are other drivers trying to get around you. Then, after a short period of time that can be anywhere from 1 to 20 seconds the transmission will engage with the engine very abruptly with a “thunk” sound and the vehicle jerking forward a foot or so. I try to not rev the engine when this problem occurs as it seems like the transmission achieves fluid lock-up suddenly and the result is the transmission parts get hammered.
The engine is running fine, and I am having no issues with it. This vehicle is very low mileage and only has 71,000 KM, (less than 45,000 miles), rolled up on it. I do not abuse my vehicles and this Colorado in particular has been treated very gently, so this problem where it feels like someone has burned out the transmission is very perplexing.
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That does sound like it’s low on fluid.I am having a problem with the Hydra-Matic 6L50 six-speed automatic transmission in my 2017 Chevrolet Colorado with the Baby Duramax engine. The problem started to occur occasionally and now is increasing in frequency. I am wondering if other Colorado and Canyon diesel owners are experiencing the same thing and if there is a recall or other solution to the problem.
I first want to say that I have looked everywhere under the hood or looking at the transmission itself and I can not find a dipstick or a viewing window for measuring transmission fluid levels. There also does not appear to be anywhere under the hood for topping up transmission fluid. This is very frustrating as the problem feels like the transmission is low on fluid.
On to the problem itself... This seems to only happen when you want to go forward with the truck from a dead stop. The problem has not appeared when I am in reverse, only when the engine is in drive with the intention of moving forward. The transmission seems to become disconnected from the engine and the engine will rev freely like it is bolted to a manual transmission and you are pressing down on the clutch or are in neutral…. with the result being no forward motion of the vehicle. This can be very hazardous when you have partially rolled into an intersection and there are other drivers trying to get around you. Then, after a short period of time that can be anywhere from 1 to 20 seconds the transmission will engage with the engine very abruptly with a “thunk” sound and the vehicle jerking forward a foot or so. I try to not rev the engine when this problem occurs as it seems like the transmission achieves fluid lock-up suddenly and the result is the transmission parts get hammered.
The engine is running fine, and I am having no issues with it. This vehicle is very low mileage and only has 71,000 KM, (less than 45,000 miles), rolled up on it. I do not abuse my vehicles and this Colorado in particular has been treated very gently, so this problem where it feels like someone has burned out the transmission is very perplexing.
Follow the video SFLTuck posted as soon as possible. If it is low it will do damage.
Question
from a stop and you put it in drive can you feel it go in gear like any other automatic transmission
If it doesn’t, slowly move the shifter towards L (low) and see if it goes in gear.
Thanks to both of you; Coloradorob and SFLTruck.
You can be sure I am going to follow up with EVERYTHING. For the time being I am using this vehicle as absolutely little as possible.
You can be sure I am going to follow up with EVERYTHING. For the time being I am using this vehicle as absolutely little as possible.
That guy is very knowledgeable and has a bunch of great videos.Thanks to both of you; Coloradorob and SFLTruck.
You can be sure I am going to follow up with EVERYTHING. For the time being I am using this vehicle as absolutely little as possible.
i have a 2018 canyon 2.8 diesel. i ed the forum and find torque converter problems. i changed the fluid at 5k,20k and 50k with the 50k service including a filter. noticed a shudder yesterday when taking off at about 30% throttle. my brother was with me and he worked service in a gm dealership and noticed it right off. currently has 55k on it. i am wondering if i should replace the torque converter wit a ev master mentioned on here i was told by service personeel that the factory torque converter is not the best quality. is the rev master a higher quality torque converter?or still under warently sould i replace it with a factory part but if it fails again should i go to the rev master???
Me personally, if I was going keep the truck for an extended duration and that close to the end of warranty that triple disk rev master would be my choice.i have a 2018 canyon 2.8 diesel. i ed the forum and find torque converter problems. i changed the fluid at 5k,20k and 50k with the 50k service including a filter. noticed a shudder yesterday when taking off at about 30% throttle. my brother was with me and he worked service in a gm dealership and noticed it right off. currently has 55k on it. i am wondering if i should replace the torque converter wit a ev master mentioned on here i was told by service personeel that the factory torque converter is not the best quality. is the rev master a higher quality torque converter?or still under warently sould i replace it with a factory part but if it fails again should i go to the rev master???
I understand your frustration. It’s even difficult to get a dealership to check the fluid level. First one told me it was a difficult procedure to check it and wanted to charge me $140 to $150. The second one told me it was a sealed unit and couldn’t be checked. After those experiences, if it were me, I would take it to a competent transmission shop for an opinion. They would probably check the fluid level, too. I would gladly trade my wireless phone charger or any of the OnStar stuff that I don’t use for a #*&@ing transmission dipstick! After spending $50,000 plus, I’ll spring for the extra $100. Just saying.
I agree with Waterbilly, GM sells a truck with a towing package they should add a dipstick. We all know that the one device in the vehicle that takes the most abuse when towing is the transmission. Yet they don't give the owner an easy way to check the fluid. I added the Lokar to to my 2018 and what sucks is there's no way to add one to the 10 speed I have now. I'm kind of bummed on that one but oh well it is what it is....
I absolutely 100% agree with you, Waterbilly. There are a lot of bells and whistles I can do without, but making it harder to service or check up on my vehicle is a BIG no-no in my book.I understand your frustration. It’s even difficult to get a dealership to check the fluid level. First one told me it was a difficult procedure to check it and wanted to charge me $140 to $150. The second one told me it was a sealed unit and couldn’t be checked. After those experiences, if it were me, I would take it to a competent transmission shop for an opinion. They would probably check the fluid level, too. I would gladly trade my wireless phone charger or any of the OnStar stuff that I don’t use for a #*&@ing transmission dipstick! After spending $50,000 plus, I’ll spring for the extra $100. Just saying.
I indeed have decided to take my truck to a well-established transmission shop here in Edmonton. They can scan for codes, check the fluid level, go for a drive with it AND flush the transmission with upgraded fluid if I want, (AMSOIL). To h*ll with the dealer!
If there is indeed damage to my transmission after 71,000 kms, GM is going to hear from me.
I am also entertaining whatever upgrades to this transmission I require to make it bulletproof. I want a transmission that can withstand 450 ft-lbs of torque at 2000 rpm for sustained periods of time.
If this means an upgraded torque converter, better clutch packs, a better pump, a deep sump pan, a shift kit, a Green Diesel Engineering transmission tune; whatever it takes. I do not want to go through this crap again. I simply have no patience for it.
Suggestions welcome, people. Please rank what you would do first and what is most important.
I am also entertaining whatever upgrades to this transmission I require to make it bulletproof. I want a transmission that can withstand 450 ft-lbs of torque at 2000 rpm for sustained periods of time.
If this means an upgraded torque converter, better clutch packs, a better pump, a deep sump pan, a shift kit, a Green Diesel Engineering transmission tune; whatever it takes. I do not want to go through this crap again. I simply have no patience for it.
Suggestions welcome, people. Please rank what you would do first and what is most important.
Next Gen Diesel has some interesting reading and offers ”built” 6L50-E transmissions. I
As you saw in my thread, I am having the same issue. It seems like this is a fairly uncommon problem, in all my searching I only found a few other cases that were similar, and not any good information on the actual problem/ cause. Will keep you posed, but I'm hoping its the valve body assembly that the transmission shop suspects.
Of course this happened 4k and 3 months out of warranty, doesn't make me feel great about keeping this truck long term.
Just FYI checking the level isn't too bad, get the transmission up to operating temp (there is a sticker on the transmission pan with the temp range) and with it running pull out the plug on the pan. Fluid should trickle out if its at the right level. If you don't get anything you can let it run a bit longer and warm up (expand) some more to see if you get anything coming out.
Adding fluid is another thing, there's a silly little rubber plug on the top of the transmission flange that you need to pop up and pull out and then get a pump or something into the hole to add the fluid. Not the easiest thing, but you should only have to do it every 50k miles or so.
Of course this happened 4k and 3 months out of warranty, doesn't make me feel great about keeping this truck long term.
Just FYI checking the level isn't too bad, get the transmission up to operating temp (there is a sticker on the transmission pan with the temp range) and with it running pull out the plug on the pan. Fluid should trickle out if its at the right level. If you don't get anything you can let it run a bit longer and warm up (expand) some more to see if you get anything coming out.
Adding fluid is another thing, there's a silly little rubber plug on the top of the transmission flange that you need to pop up and pull out and then get a pump or something into the hole to add the fluid. Not the easiest thing, but you should only have to do it every 50k miles or so.
We have a 2019 in The Philippines with 52000km. The problem here is worse since NO ONE has any idea how to check, service or repair these at all. I have changed the fluid and filter myself using Amsoil fuel efficient fluid and added a cooler. It no longer slips out of gear or chatters when shifting under normal load or on small hills. But, if I go into the mountains, on the very steep grades either going up or down I can feel it slipping. To me the line pressure seems low. Is there a way or a part that can increase the line pressure, even if it makes the shift firmer. I'll be back in the US next month so I can buy any part needed then. Thanks the dog
Others can chime in with more knowledge but I would go with a Transmission tune. I'm not up to speed on the various tunes and which ones are best for your situation.We have a 2019 in The Philippines with 52000km. The problem here is worse since NO ONE has any idea how to check, service or repair these at all. I have changed the fluid and filter myself using Amsoil fuel efficient fluid and added a cooler. It no longer slips out of gear or chatters when shifting under normal load or on small hills. But, if I go into the mountains, on the very steep grades either going up or down I can feel it slipping. To me the line pressure seems low. Is there a way or a part that can increase the line pressure, even if it makes the shift firmer. I'll be back in the US next month so I can buy any part needed then. Thanks the dog
I had a Green Diesel Engineering ECM and trans tune and I really like it. Shifts were firm (not too firm) and predictable unlike the factory software. Between doing a full fluid swap with Mobile blue label LV HP transfluid and the TCM tune it was very worth while. The shifts were buttery smooth but firm if you dug into the throttle pedal.Others can chime in with more knowledge but I would go with a Transmission tune. I'm not up to speed on the various tunes and which ones are best for your situation.
So I had similar prob with my 2017 colorado where I wood be at a red light step on gas and all I got was revs wood shift it in to different gears and nothing happen to me twice till I took it to dealer sucks when u take it in and they can’t replicate the problem they end u telling I must of some how put it on 4high and that’s was the problem I knew that’s wasn’t but lucky for me when I picked it up I couldn’t leave the service department cuss still had the problem the look on there face when they had told me it was fixed in the end what it was that valve body where scored valve sticking in valve body check ball in valve body also damaged and pieces disperse in valve body bore lineups I have word order sheet but not sure how to post pictures on hereI am having a problem with the Hydra-Matic 6L50 six-speed automatic transmission in my 2017 Chevrolet Colorado with the Baby Duramax engine. The problem started to occur occasionally and now is increasing in frequency. I am wondering if other Colorado and Canyon diesel owners are experiencing the same thing and if there is a recall or other solution to the problem. I first want to say that I have looked everywhere under the hood or looking at the transmission itself and I can not find a dipstick or a viewing window for measuring transmission fluid levels. There also does not appear to be anywhere under the hood for topping up transmission fluid. This is very frustrating as the problem feels like the transmission is low on fluid. On to the problem itself... This seems to only happen when you want to go forward with the truck from a dead stop. The problem has not appeared when I am in reverse, only when the engine is in drive with the intention of moving forward. The transmission seems to become disconnected from the engine and the engine will rev freely like it is bolted to a manual transmission and you are pressing down on the clutch or are in neutral…. with the result being no forward motion of the vehicle. This can be very hazardous when you have partially rolled into an intersection and there are other drivers trying to get around you. Then, after a short period of time that can be anywhere from 1 to 20 seconds the transmission will engage with the engine very abruptly with a “thunk” sound and the vehicle jerking forward a foot or so. I try to not rev the engine when this problem occurs as it seems like the transmission achieves fluid lock-up suddenly and the result is the transmission parts get hammered. The engine is running fine, and I am having no issues with it. This vehicle is very low mileage and only has 71,000 KM, (less than 45,000 miles), rolled up on it. I do not abuse my vehicles and this Colorado in particular has been treated very gently, so this problem where it feels like someone has burned out the transmission is very perplexing.
See coloradofans.com for the solution and history. This has been a problem with the gasser but not the diesel bc the torque converters are very different. I had the dealer flush mine (2019 Colorado 2.8), drop the pan and replace the filter and replace with the new GM fluid. Towing a 5K# Apex Nano.I am having a problem with the Hydra-Matic 6L50 six-speed automatic transmission in my 2017 Chevrolet Colorado with the Baby Duramax engine. The problem started to occur occasionally and now is increasing in frequency. I am wondering if other Colorado and Canyon diesel owners are experiencing the same thing and if there is a recall or other solution to the problem.
I first want to say that I have looked everywhere under the hood or looking at the transmission itself and I can not find a dipstick or a viewing window for measuring transmission fluid levels. There also does not appear to be anywhere under the hood for topping up transmission fluid. This is very frustrating as the problem feels like the transmission is low on fluid.
On to the problem itself... This seems to only happen when you want to go forward with the truck from a dead stop. The problem has not appeared when I am in reverse, only when the engine is in drive with the intention of moving forward. The transmission seems to become disconnected from the engine and the engine will rev freely like it is bolted to a manual transmission and you are pressing down on the clutch or are in neutral…. with the result being no forward motion of the vehicle. This can be very hazardous when you have partially rolled into an intersection and there are other drivers trying to get around you. Then, after a short period of time that can be anywhere from 1 to 20 seconds the transmission will engage with the engine very abruptly with a “thunk” sound and the vehicle jerking forward a foot or so. I try to not rev the engine when this problem occurs as it seems like the transmission achieves fluid lock-up suddenly and the result is the transmission parts get hammered.
The engine is running fine, and I am having no issues with it. This vehicle is very low mileage and only has 71,000 KM, (less than 45,000 miles), rolled up on it. I do not abuse my vehicles and this Colorado in particular has been treated very gently, so this problem where it feels like someone has burned out the transmission is very perplexing.
Hell... I might as well chime in. Mine started acting up yesterday.
2019 ZR2 with 31k on the clock ..
Out of the blue, Ill be light throttle cruising 45 or so.. it will be in 6th gear. I depress the pedal to accelerate or pass and I get a high pitched grinding noise, loud as hell from under the truck before it downshifts.. oh yay.. now I have to find a way to diagnose this bullshit and fix it.
Anyone have any insight?
No other gear, just 6 to 5 downshift on acceleration.
2019 ZR2 with 31k on the clock ..
Out of the blue, Ill be light throttle cruising 45 or so.. it will be in 6th gear. I depress the pedal to accelerate or pass and I get a high pitched grinding noise, loud as hell from under the truck before it downshifts.. oh yay.. now I have to find a way to diagnose this bullshit and fix it.
Anyone have any insight?
No other gear, just 6 to 5 downshift on acceleration.
And no it did not set any codes at all.
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