Rubyralph

Thank you everyone for your post’s! I retested my signal skills this morning going to breakfast…and it worked! l was holding the signal stock down too long, more than a second. Thanks for saving me an embarrassing trip to my dealership! (Which is 30 miles North)! This is my second 1500 with the 3.0 duramax, I ready like all the small improvements over the 2020 1500 LM2 and the interior was worth the trade alone. Can’t wait to get some miles on the truck and tow my trailers to see how she handles. Thanks again to everyone who posted!!

Just traded my 2020 Chevrolet 1500 LT for a new 2023 GMC Sierra 1500 SLE. One feature I noticed missing was one I enjoyed on my 2020 is the turn signal touch to pass 3 blinks per touch, 6 when in tow/haul mode. This feature is completely missing on my new truck? Is this normal or did GM change something? Going t contact the dealer but wanted to see if this is normal

I’m having the same issue with my LM2 at 8K miles. Had the dealership check for leaks but the only way they will confirm a coolant leak is to document it over some miles. I made the mistake of topping off both tanks twice myself. I’ve noticed a coolant smell in the garage after diving, some said this is normal, I never had a vehicle smell of coolant unless there was a leak in 50 years of GM ownership.

Installed picture, glad I found this easy mod to help me get into my truck's bed!

Well I no longer than sent this out and I got a call that my parts were in so here yo go: Parts required for my truck's steel box with the one piece tailgate: Tailgate Handle part number is now 84726114. Hardware for factory DIY Tailgate Handle install: Backup plate bracket 84338560. 8mm-1.25 nuts for backup plate 11546459 (2 required) 8mm-1.25x 24.5 long bolt for truck box 11602770 (I re-tapped the box threads as my factory spray-in liner required it) Works great for me, hope this helps!

Ordered my Tailgate Handle a week ago from my dealer and I can confirm it doesn't come with the hardware. I will post the hardware part numbers as soon as I receive my order and confirm the three hardware part numbers. BTW the correct Tailgate Handle part number is now 84726114. I'll also will post some pictures of all the parts before it's installed as it's a simple install. Looking forward to try this handle out as I'm having trouble accessing the truck's bed area.

Truck is still running great with no CEL issues. I do still have the “muffled Jake brake” noise when coasting down at low speeds. Not sure if it’s normal for all 3.0 trucks See my first post for all the parts the dealership replaced to clear my CEL.

6k miles and still have the noise, normal for my truck, check my other posts about my DEF system. Dealership replaced the entire DEF tank, pump, heater and wiring harness, seems to work now. Towed 4K lbs. 300 miles last Sunday and the truck towed great and even downshifted in tow/haul with cruise control on down a long grade at 50 MPH! Very happy with the truck now if I can stay out of the dealership!! !

I will be following this closely as my truck started making noise last Friday on our first warm day. We went on a 120 mile round trip it was 75 degrees, I noticed the jungles soon after the truck was warmed up and didn’t say a word to my wife. I wear hearing aids and couldn’t determine the source but on the return trip my wife asked what the noise was...and my truck only has less than 5K miles! So on the next warm day this week I will try the 4WD mode to see if that changes the noise. I'm so happy I saw this as I knew the dealer wouldn’t of been able to confirm any noise, hopefully GM can fix our trucks the first time this time!

I have had DEF related CEL(s) since new, I now have ~4K miles and have had at least 4 CEL at the dealership, they just replaced the following parts: 84914535 tank, 84620945 harness, 84714454 controller, and 3 1/2 gallons of DEF fluid. My issues began when new from the factory when the same dealer said that the DEF pump connector pins were wired wrong! I hope this resolves my DEF problems as I plan on some long road trips this summer and I really want to enjoy the truck but I'm losing all hope of it being repaired correctly, which is a shame because I love the drivetrain of this truck.

Thanks guys for your help...I have contacted both Titan and TransferFlow through their website's contact links. Both haven't responded yet, I don't want to spend time and money to find out I may have installation or operational issues ie: the emission system CEL that my truck seems to have enough of on it's own. So I'm still looking for someone who has installed a auxiary diesel LM2 tank and what they have had for results in our T1 1500 series trucks. Thanks again, Ralph

Has anyone that owns a 2020/2021 3.0 Duramax LM2 pickup installed a in-bed auxiliary fuel tank to extend towing range? I'm interested in the T____n fuel tanks but they don't offer a kit for the LM2 as yet. Thanks Ralph

I have had DEF related CEL(s) since new, I now have ~4K miles and have had at least 4 CEL at the dealership, they just replaced the following parts: 84914535 tank, 84620945 harness, 84714454 controller, and 3 1/2 gallons of DEF fluid. My issues began when new from the factory when the same dealer said that the DEF pump connector pins were wired wrong! I hope this resolves my DEF problems as I plan on some long road trips this summer and I really want to enjoy the truck but I'm losing all hope of it being repaired correctly, which is a shame because I love the drivetrain of this truck.

Interesting... My truck threw a CEL this week (emission message, 160 miles until limited speed 65 MPH) this was the second time in 800 miles and my truck only has 3800 miles on it. I have had 5 CEL since new three times in the dealership, the other two cleared after second or third ignition cycles. The first time was during the test drive with only 55 miles on the odometer! Every time the dealer said it was the emission system related to the DEF system, DEF tank heaters and now the pump. This week the service manager said they had to order parts i.e. a coolant? pump, hoses, and a control module. Sorry I don't have any codes or part numbers to share but when the parts are in and replaced I will follow up. Also I have only shown two gauge bars of DEF fluid used since new, I have always felt the DEF system wasn't injecting enough DEF into the engine, maybe I was correct? Side note my last tank MPG was low 23 MPG highway mostly, I filled up after my service appointment this week and saw a improvement to 31 MPG highway which made me feel better...at least for now!

Wow I'll try that tomorrow!!! Thanks ?

Strange story but I'll break it down and make it as simple as I can... Bought my new 2020 Duramax back in April, during the test drive at the dealership I noticed a CEL and pointed it out to my salesman. The Dealership cleared the CEL before delivery (55 miles on the odometer) and the repair order said they replaced the "Emission Reduction Fluid Tank" because the reductant heater 3 current was high scan code: P221F. Fast forward to 2400 miles, After mixed driving and towing maybe 200 miles of towing total I noticed two things about my 3.0 Duramax, first the engine always made a muffled noise when coasting below highway speed, sounded like a mini Jake brake. Secondly I hadn't seen any drop of DEF on the dash screen until after 2400 to 2985 miles and then just one bar. So today I got my free LOF and tire rotation and wouldn't you know on my drive to the dealership I got a CEL Emission warning "169 miles to reduced 65 MPH speed" The Techs repair order states that codes "2985 P21DD 00 P221E were set in ECM, the fix was to install a recall "N202300791 Diesel Exhaust Fluid Inactive Recall" per recall reprogrammed exhaust fluid module. Now maybe it was the recall or something else the Tech found but now my truck's Duramax engine is NOT making the muffled noise when coasting below highway speed and I think I actually can hear a very faint turbo wine when accelerating! I hope ever thing is now fixed correctly? Has anyone with the new 3.0 Duramax heard of this happening? Thanks

When my truck was brand new I backed up to my trailer and tried this feature highlighted in red. I ready liked it at the time and thought the GM Engineers ready did a great job designing the software, but now I can't seem to make this feature work? The dealer said its working at designed?? Has anyone else tried or had issues with useful feature? When I backup now with the "hitch view" camera and shift into park, I roll back an inch or so unless I manually engage the parking brake. My question is for anyone that owns a 2020 Silverado LT this highlighted text was copied and pasted from our Owner's Manual in the Driving and Operating section Rear Vision Camera (RVC) para:8 8. Hitch View Assists with connecting to a trailer by providing a zoomed-in view of the hitch to help align the vehicle’s hitch ball with the trailer coupler, or to monitor the trailer connection. To select, touch Hitch View on the infotainment display when a camera view is active. To access this view when in a forward gear above 12 km/h (8 mph), touch CAMERA on the infotainment display and touch the Cargo Bed View icon. The view will close after 8 seconds and can be closed early by touching X. Shifting into P (Park) while in this view will automatically engage the Electric Parking Brake (EPB).

What highway MPG do you get and what’s your RPM @ 70 MPH? thanks Ralph

What kind of Highway MPG do you get with the 3.73 gears? Most others that are getting 30 MPG highway unloaded have the 3.23 gears like mine. I think your truck has the "diesel off-road" package? Thanks

If you encounter any down hill grades while towing please try the exhaust brake with TH and cruise control and no cruise control. TFL had poor results with this test and I would like to see if other driving techniques would help engage the exhaust brake sooner? Thanks.

I have the same question...I'm thinking about getting my truck in to be checked because according to my DEF gauge I have a full DEF tank since new with about 3K with a little towing. Seems like everyone uses a lot more DEF after the update?

My dealership filled my DEF tank when I took delivery of my new 2020 Silverado 1500 3.0 Duramax, I now have ~1800 miles on the truck and the DEF gauge still reads full, when will I see a drop on the DEF gauge? Mostly highway miles not towing yet, average mileage 27.9 to 29.1. Love the truck but I'm starting to wonder about my DEF usage???

The "diesel off-road package" RPO code B4U trucks must be kind of rare, I never found one near me when I bought my 2020 truck. Please continue to share your towing driving reviews and mpg results with the rest of us Duramax 3.0- 3.23 ratio folks. ?

Thanks ?

What purpose is this hole for, located on bottom the passenger side mirror only?