Slippery

All,

A service update exists for 2020 & '21, HD Chevy / GMC 2500 / 3500 equipped with the 6.6 D-MAX.

However, we're understanding the update does not apply if your truck started life as a cab & chassis, so it appears to be pickup only. (dunno, different tank location so maybe a different, more robust harness)

The DEF tank harness connector can overheat (melt) which will then send the truck into "Limp Mode".

UPDATE: One of my guys just spoke with a customer of ours who is in FL and the dealer he contacted there not only hadn't heard of the bulletin, refused to perform the update. I don't understand that, because GM pays us to do it, but whatever....

The issue is related to the DEF tank heater, which shouldn't be as much of an issue there, (because it never gets cold there, right ?) but once he heads home could result in a problem. We advised him to contact another dealer and if he can't get it done to contact us and we'll contact GM on his behalf and see where they want him to go. . He could push the OnStar button for assistance but contacting us is probably faster in a situation like this. If anyone else has an issue with a local dealer being reluctant to perform the update I'd recommend contacting GM or send me a dm and I'll try to provide contact info for you.

During normal times that would be aggravating.

Unfortunately, these aren't normal times and parts availability at a national level isn't good. Not hopeless, but not good. I'm trying hard not to say "it sucks" but you get the idea.

The vehicle software needs to be recalibrated & my tech's are telling me it's a simple update which usually can be completed in under 1/2 hour.

We've already had customers experience this issue prior to the bulletin and replaced hard parts, but this doesn't resolve the issue. IE Even if you've experienced the issue and had it "fixed", unless the dealer also did the software update, you're likely to experience it again.

It's a "Service Update" as opposed to a safety recall, so at this point there are no factory notifications being sent that I'm aware of.

Don't shoot the messenger; I'm not going to get into what I think about GM not reaching out to affected owners (unless we share a cold one somewhere & I'll tell you exactly what I think of it).

I'm gonna insert a shameless plug here - because it's an "update" and not a recall requiring notification, this is a perfect example of why you should visit your dealer for at least some of your maintenance; your local shop probably isn't aware of the condition and doesn't have a good way to look for it unless they're aware of it.

It's also a good reason to get your HD from someplace that makes a commitment to stock and sell HD's...those dealers are probably aware of the required update, while stores with salespeople who don't know the difference between a gooseneck and 5th wheel hitch probably don't have a clue .....we know about it, but it took me a few days to wake up and realize I need to post this so hopefully someone can avoid some grief.... apologies for the low awareness factor..it's winter and all of us in the great white north are drinking and dreaming of good weather.

So...if you've got a '20 or '21 GM HD Pickup with a D-Max, it probably needs the update.

If you've had the issue and it was fixed prior to 2/4/22, it probably needs the update.

Think Spring

d

Cory H

Another reason to keep my old rust free low mile LBZ!!!!!!!!!!!!!!

Slippery

lol...tough to argue with that logic

I'd like to meet the guy who thought "let's use goat urine as a catalyst and burn the gunk out of a particulate filter we put behind a Diesel engine". WTF was he smoking ?

I'd also like to meet the guy who approved the idea....it'd be like meeting the 2nd guy who thought it would be a good idea to give Bob Dylan a microphone...apologies to Dylan fans...he's a great poet but his voice is an inspiration to every wannabe singer because "if he can sing, I can sing".

If I'm understanding correctly, it's a simple matter of too much voltage...which could happen in any number of connections in the miles of wiring harness in all new vehicles. Easy fix & it 's that whole "ounce of prevention vs pound of cure" thing....

Electronics are great...it's why our modern vehicles will do what they do, but the whole industry struggles with tech issues and updates...

Cheers

Robi523

Will have to take mine in I guess...

Slippery

We've contacted our customers and put the word out as much as possible.

We currently have 3 trucks in our shop waiting for DEF tanks.

The latest update states there are no tanks available and provides no info re when the next update is going to be available.

The issue is with the DEF heater, so as long as you're somewhere where it doesn't get cold, you "shouldn't" have a problem, but if an event occurs, the truck is likely going to go into limp mode.

The joke about the definition of "back order" being "They just planted the trees to make the boxes to ship the parts in" is no longer a joke. It doesn't seem to matter whether is houses, vehicles, boats, tractors, ...whatever...nearly every industry is struggling with parts availability.

SkiDoc

iTrader: (4)

Thanks for the information. Would a 2022 have the same problem if manufactured in 8/22?

MonkeySea2

this happened to my 2016. Had to have the whole DEF tank replaced. Glad it was pre-covid