Hard shift from park to reverse

[AD80]

On my 5.3 8 speed with  less than 500 miles,  when i put it in reverse, from either park or drive, it slams or jerks into gear.  It feels like the same jerk you get when parked on a slight incline or when you shift before the rpms have settled down after start up. But in my case i can be on level ground with the rpms at low idle and i still get it. It doesnt do it when shifting into drive, just reverse. I noticed that when i go to neutral then back to reverse its still does it but not as bad, but straight from park to reverse is when its the worst. I know in general, this isnt normal, but is it normal for these 8 speeds? Btw, it shifts smooth while driving, so no problems there.

Edited November 8, 2019 by AD80

[SamDSJR]

Mine is brand new too. I'm a little worried about mine as well. Mine doesn't quite do what yours does, but its still not as smooth as I would like.

 

So mine jerks shifting from Park to Drive. If I let the truck warm up for a good while (5-10 minutes) before shifting into Drive it will not do it. I also have a weird noise going from Drive to Neutral. I get this strange hollow sound like a marble is falling into an aluminum can. Really weird. And only makes the noise from Drive to Neutral. Not any other combination to Neutral.

But just like you said - my transmission is butter smooth while driving so I guess I won't worry about it.

[AD80]

1 hour ago, SamDSJR said:

Mine is brand new too. I'm a little worried about mine as well. Mine doesn't quite do what yours does, but its still not as smooth as I would like.

 

So mine jerks shifting from Park to Drive. If I let the truck warm up for a good while (5-10 minutes) before shifting into Drive it will not do it. I also have a weird noise going from Drive to Neutral. I get this strange hollow sound like a marble is falling into an aluminum can. Really weird. And only makes the noise from Drive to Neutral. Not any other combination to Neutral.

But just like you said - my transmission is butter smooth while driving so I guess I won't worry about it.

Mine feels like older trucks do when they have bad u joints and slack. Like I said, it’s  only when going to reverse from park.  Going to drive is so smooth,I can’t even feel it engage.  My dealer is 100 mi away and I don’t want to drive that far just To have them tell me it’s normal. Maybe after more miles it’ll get a little more broken in and loosen up.

Edited November 9, 2019 by AD80

[econometrics]

Common issue. Read / search the forum some and you'll see this has happened to many of us. 

There ARE some technical bulletins out for this, where you can go in and have your transmission fluid changed out. But that's only if your truck was built before 1 March 2019. 

 

To ease your mind, my RST did this to me 2-3x in the first 3000 miles. Now I have 6500 miles on it and it hasn't done it in months. 

 

I'm also a more gentle with it putting it into R-N-D or vice versa. I can tell now when it's going to shift harshly and I don't apply gas to let it torque down a little. 

[AD80]

55 minutes ago, econometrics said:

Common issue. Read / search the forum some and you'll see this has happened to many of us. 

There ARE some technical bulletins out for this, where you can go in and have your transmission fluid changed out. But that's only if your truck was built before 1 March 2019. 

 

To ease your mind, my RST did this to me 2-3x in the first 3000 miles. Now I have 6500 miles on it and it hasn't done it in months. 

 

I'm also a more gentle with it putting it into R-N-D or vice versa. I can tell now when it's going to shift harshly and I don't apply gas to let it torque down a little. 

That good to hear that yours went away after a few miles. Mine was built on 6/19, so it should have the updated fluid. I’m also careful and won’t put it in reverse until the rpms come down all the way after start up, but it still does it. I crawled under and the drive shaft seems tight. Mine only has 500 mi, and I haven’t used 4x4 yet, so I’m gonna go put it in 4x4 and run it forward and reverse a couple times to see if maybe that will do anything.  It might be something in the transfer case, who knows. Maybe it will free up.

[econometrics]

6 minutes ago, AD80 said:

That good to hear that yours went away after a few miles. Mine was built on 6/19, so it should have the updated fluid. I’m also careful and won’t put it in reverse until the rpms come down all the way after start up, but it still does it. I crawled under and the drive shaft seems tight. Mine only has 500 mi, and I haven’t used 4x4 yet, so I’m gonna go put it in 4x4 and run it forward and reverse a couple times to see if maybe that will do anything.  It might be something in the transfer case, who knows. Maybe it will free up.

I can almost tell you with certainty it’s not the transfer case. This is an issue a lot of 8 speed owners have reported. But hey, give it a try. I haven’t read here that any have tried that. 
 

It WILL smooth out, though. I can assure you of that. It’s a great transmission, IMO. Gets a lot of bad press, but I think it’s a small minority of owners. 

[AD80]

53 minutes ago, econometrics said:

I can almost tell you with certainty it’s not the transfer case. This is an issue a lot of 8 speed owners have reported. But hey, give it a try. I haven’t read here that any have tried that. 
 

It WILL smooth out, though. I can assure you of that. It’s a great transmission, IMO. Gets a lot of bad press, but I think it’s a small minority of owners. 

I hope it will, and other than the reverse engage, i have no complaints while driving, it shifts and downshifts so smooth, i cant even feel it most of the time. 

[Jbobbuffington]

Any issues since then? I just bought the same truck with less than 500 miles and it’s shifting hard into reverse too. 

[Vicarod]

My truck does this as well...Sadly I think it is a characteristic of the 8spd. 

I let the truck do a full needle sweep of the gauges before I put it into gear.  That usually alleviates the slam into reverse.  I think letting the transmission  start pumping fluid when first starting -- especially after sitting all night for example -- goes a long way in solving that problem.

Other than that, the transmission is smooth.  I do believe that it takes a few thousand miles for the transmission to "learn" your driving habits.  I am not too clear on that, so if someone else knows, please correct me.  All of that to say that I do feel the truck is smoother now with 18k on the clock then when I drove it off the lot with 25 miles on it.

[redwngr]

https://gm-techlink.com/?p=13727

 

Delayed Transmission Engagement

September 30, 2020

Some 2018-2019 ATS, CTS, CT6, Corvette; 2018-2020 Express; 2018-2021 Camaro, Colorado, Silverado, Canyon, Savana, Sierra; and 2021 CT4 models equipped with the 8L45 or 8L90 8-speed automatic transmission (RPO M5T, M5N, M5U, M5X, MQD, MQE) may have a delayed engagement condition when the transmission is shifted from Park to Reverse or Park to Drive after the vehicle has been sitting with the engine off. (Fig. 12) The delayed engagement typically occurs after several hours or, more commonly, overnight.

 

Fig. 12

 

The condition may seem to be delayed gear engagement, a slipping transmission, or delayed engagement followed by a harsh engagement.

The transmission is designed to allow three seconds to complete a garage shift (shifting from Park to Reverse or Park to Drive). If the engine speed is increased before the transmission has engaged, the garage shift may be harsh.

After the initial shift, transmission operation will be normal for the subsequent engagements. The condition will not occur again until the vehicle sits again with the engine off for several hours or overnight.

 

Delayed Engagement Test

Use GDS2 to monitor engine RPM and the transmission input speed sensor (ISS) prior to starting the engine. Start the engine with the transmission in Park and shift the vehicle from Park to Drive or Park to Reverse with the service brake applied. The ISS should drop to zero within three seconds, which is the clutch engagement time. Recording the GDS session log can be useful in diagnosing the condition.

Delayed engagement of Park to Reverse or Park to Drive is present if the time difference between the gear selected (Pt. 1) and the transmission input shaft speed reaching 0 RPMs (Pt. 2) exceeds three seconds. (Fig 13)

 

Fig. 13

 

In most cases, the transmission will engage in three seconds or less, which is considered an acceptable engagement time and no repairs should be attempted.

TIP: The vehicle should only be evaluated after sitting for a minimum of eight hours but less than 24 hours and at an ambient temperature of 50°F (10°C) or above.

If engagement time exceeds three seconds, attempt to learn the C3 – Drive and C5 Reverse – Clutch using the following steps:

1. Allow the transmission sump temperature to rise between 20° and 30°C (68° and 86°F). Do not apply the accelerator pedal.
2. Perform 20 Park to Reverse shifts or 20 Park to Drive shifts releasing the brake pedal with each shift, allowing the vehicle to roll 5-10 feet (1.5-3.0 m) per engagement into gear.

 

If the learn procedure does not correct the condition, disassemble the transmission and inspect the 1-3-5-6-7 Clutch (C3) for a delay into Drive condition and inspect the 4-5-6-7-8 Reverse Clutch (C5) for a delay into Reverse condition. The respective clutch plates and seals should be inspected for wear and or damage and repaired accordingly.

If the vehicle has less than 2,500 miles (4,000 km), the transmission or valve body has been replaced or a clutch repair has been performed, follow the clutch learn procedure in Bulletin #16-NA-019 to learn the C5 Reverse and C3 Drive Clutch.

For additional information on a delayed transmission engagement condition, refer to Bulletin #20-NA-187.

[PuffDr4gon]

This has happened to me in my 21 LT Trail Boss with 6.2L 10 speed going from P to D. Less than 300 miles. I'll keep and eye on it.

[zbinder33]

I had my 19 RST in the dealership today for this issue and I was directed to a Chevy bulletin that says this is a normal function of the transmission. Every morning I start my truck, put it in drive and go to leave my driveway and my transmission hangs up at the top of 1st and sometimes 2nd, and the shift is rather abrupt after the hang up. Apparently it’s caused by air in the clutch plate that purges over the first 2-3 upshifts. Chevy literally put in their bulletin that “no repair attempts shall be completed”. All they told me was it has everything to do with transmission temp and they way the POS 8 spd is to supposed to work. Sort of hard to believe that it’s normal but hey what can we do. 

[Miles J]

I have a 2021 GMC Canyon AT4. Got it brand new and 3 different dealerships have said this is "Normal". They tried resetting some type of 'adapter' as well as adding moisture but neither worked. Please advise. Thinking about trading in now to avoid any problems later. 

[GMCustomerService]

On 9/7/2022 at 11:59 AM, Miles J said:

I have a 2021 GMC Canyon AT4. Got it brand new and 3 different dealerships have said this is "Normal". They tried resetting some type of 'adapter' as well as adding moisture but neither worked. Please advise. Thinking about trading in now to avoid any problems later. 

This is certainly not what we like to hear, Miles J.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2021 GMC Canyon AT4. To do so, please send an email to [email protected] with ATTN: Miles J/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s privacy policy, please visit https://www.gm.com/privacy-statement.html.
 
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[Scout Rob]

My 2022 Colorado ZR2 has been hard shifting into reverse with a loud clunk causing the truck to buck as well as hard down shifting from 2nd to 1st with a loud clunk and it lunges forward. I have taken it to two different dealerships with both stating "unable to duplicate". They failed to realize that I have a dash cam in my truck and they never once put it into reverse. The 2nd dealership I took it to, I literally made the service writer sit in the truck with me while I played 8 different videos where he could clearly hear it and see the truck bucking. He even was surprised and stated that it wasn't normal. They kept my truck for 3 days and upon picking out up, they told me that they couldn't duplicate it and handed me a packet from GM regarding a hard up-shift from 1st to 2nd. I reminded them that I don't have that problem, mine was a downshifting problem and a reverse problem. I also reminded them that they literally sat in the truck and watched 8 different videos proving the issue and that he did it wasn't normal. I was simply told that that is what the transmission guy told him... Sadly, this was the first American vehicle I have bought for myself in 16 years, and this was the reason I stopped buying them. My 2012 Frontier never gave me a single problem, I only bought this truck because an idiot in a jeep crashed into my Frontier when it was parked, totaling it. 

 

 

 

 

 

 

 

I'm not sure the quality it will upload the video

 

 

 

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Update: Unfortunately the video would only upload the audio. 

 

 

 

I might have to follow Mike J's direction and just trade it in for a Frontier to avoid future problems. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited February 15, 2023 by Scout Rob