2022 Suburban stalled in middle of freeway

[Tinbadtin]

4800 miles, 3.0 diesel LS suburban.

Was in stop and go traffic coming down to a stop, went to accelerate again but not moving (still in D) and threw a check engine light. Trying to put in park and then back in gear, not doing anything. Message appeared no shift condition. Trying to cycle on/off, car will not get into gear. Meanwhile I’m stopped in the middle lane with traffic piling up behind me. After a minute or so another cycle it finally goes into gear and off I go. Made it home but check engine light still there. Getting it towed to dealership today, not wanting to risk getting stalled again.

Read the codes (see screenshot). Looks like generic transmission code…

Anyone else experience this?


Will update after I hear back…

 

[StephenPT]

Could be transmission control module - could be wiring issue.

I took have a base model LM2 and I've been poking around under the hood/chassis as much as possible to see if any harnesses are touching places they shouldn't. There's a labyrinth of wiring on these vehicles - even the base model and though GM designed a fair amount of wire routing guides and clipping points, there's always a chance that the person on the line that day didn't add the zip-tie or clip that is needed to keep the harness from rubbing against something else.

There's an extensive TSB from GM that covers many engines, including LM2 and areas to look for wiring harness chaffing. I'd take a look and see if you can find anything on your own.

https://static.nhtsa.gov/odi/tsbs/2021/MC-10205552-9999.pdf

 

[Tinbadtin]

Thanks, that’s a good suggestion however it’s already been picked up. Waiting for them to get back to me tomorrow..

 

[Tinbadtin]

Not much of an update but my case has been escalated to GM and the dealer is waiting to hear back from them. That was on Friday morning and they said it will take at least until Wed.

Meanwhile they gave me a new 1500 Custom trim as a loaner with the 2.7 and I have to say I’m very impressed with that engine. It’s peppy and has plenty of get up and go. The 8 speed is still a bit jerky but when combined with the 10 speed GM has likely a winner here. Much more lively than the lazy slouch of a 5.3 but with diesel-like fuel economy (as long as you don’t have a lead foot). I’m really impressed with it and not surprised they are making it the base engine for all the T1xx trucks with SUVs to follow soon I assume.

Although I still prefer my diesel over it it’s not by much and I can see where the use case for the diesel entirely disappears with this 2.7. It delivers pretty much the same HP/torque without the all the added complexities/inconveniences of running diesel.

 

[WalleyeMikeIII]

The 2.7l rated MPG is only about +1 to the 5.3 on the highway.

2.7: 17 city/20 hwy
5.3: 15 city/19 hwy
6.2: 14 city/18 Hwy
3l Duramax: 22 city/26 Hwy

All numbers from fuel economy.gov for 2022 Silverado 4wd, auto start/stop

Compare Side-by-Side

Compare the MPG of cars and trucks side-by-side. Compare the gas mileage and greenhouse gas emissions of new and used cars and trucks

www.fueleconomy.gov

 

[Tinbadtin]

Finally received my ride back today after exactly 2 weeks at the dealership. Service advisor initially said there was an issue with the TCM and they were waiting for parts. However after pressing for more info today before picking up it seems they replaced the transmission valve body, per paperwork.

 

[DuraYuk]

Not much of an update but my case has been escalated to GM and the dealer is waiting to hear back from them. That was on Friday morning and they said it will take at least until Wed.

Meanwhile they gave me a new 1500 Custom trim as a loaner with the 2.7 and I have to say I’m very impressed with that engine. It’s peppy and has plenty of get up and go. The 8 speed is still a bit jerky but when combined with the 10 speed GM has likely a winner here. Much more lively than the lazy slouch of a 5.3 but with diesel-like fuel economy (as long as you don’t have a lead foot). I’m really impressed with it and not surprised they are making it the base engine for all the T1xx trucks with SUVs to follow soon I assume.

Although I still prefer my diesel over it it’s not by much and I can see where the use case for the diesel entirely disappears with this 2.7. It delivers pretty much the same HP/torque without the all the added complexities/inconveniences of running diesel.

I wouldn't be surprised to see the 2.7 turbo offered on the refreshed suv in 2024. It is compelling for all the reasons you mentioned.

 

[Tinbadtin]

I wouldn't be surprised to see the 2.7 turbo offered on the refreshed suv in 2024. It is compelling for all the reasons you mentioned.

Right, it makes a lot of sense as a base engine. As much as I enjoy a good V8, I can’t think of a good reason to take the 5.3 over it other than “it sounds like a V8”.

The 2.7l rated MPG is only about +1 to the 5.3 on the highway.

2.7: 17 city/20 hwy
5.3: 15 city/19 hwy
6.2: 14 city/18 Hwy
3l Duramax: 22 city/26 Hwy

All numbers from fuel economy.gov for 2022 Silverado 4wd, auto start/stop

Compare Side-by-Side

Compare the MPG of cars and trucks side-by-side. Compare the gas mileage and greenhouse gas emissions of new and used cars and trucks

www.fueleconomy.gov

I have no reason to doubt this data but in my (limited) experience it is surprising to see these being so low. In the two weeks I had it, the 2.7 certainly felt more fuel efficient than 5.3 +1. These numbers seem overly optimistic for the 5.3 and overly pessimistic for the 2.7 to me. My experience is much better numbers in the 2.7 if you drive it gently. On the other hand, no matter how much I babied the last 5.3 I had, it would barely get over 15mpg combined. Again, this is all just based on my personal experience. Turbo drivetrains do tend to produce a wider range of economy depending on how much you make the turbo work so that likely explains some of the delta too…

 

[tom3]

I notice in all the current ads for the trucks they all push the high output turbo engine, no mention at all that it's a four cylinder. Considering GMs reputation with four bangers I can understand why.

 

[DuraYuk]

I notice in all the current ads for the trucks they all push the high output turbo engine, no mention at all that it's a four cylinder. Considering GMs reputation with four bangers I can understand why.

Gm has made some pretty sweet 4 cylinder engines. What's the reputation you speak of? The 2.7 is a really well engineered motor. The issue comes from people that think it's too new school. When it's better then the 5.3 in every way.