Epsilon Plus

A direct fit transmission dipstick is available for 2020-2023 HDs using part numbers from a 2019 model. You will need the following: Dipstick tube: 24265546 Dipstick (indicator): 24271875 Seal/grommet for dipstick tube: 15796802 (1) Flange Nut or lock/flat washer & nut: M8-1.25 Start by crawling under the truck and removing the heat shield between the pass. side catalytic converter and the transmission. Use a 10mm socket (if you can find one ) for the front bolt and a 13mm deep socket for the rear flange nut. A 1/4 inch drive ratchet works well in these tight spaces, but a box end wrench will do as well. Next, dampen a paper or shop towel and reach up and clean around the area of the dipstick tube boss to limit dirt and grime from entering the transmission during tube install. Now, raise the center pin in the factory installed plug to prepare for removal. I was able to use my fingers but a small flathead screwdriver or trim removal tool would work if yours is stuck. Next, we are going to pry up the remainder of the factory installed plug. I used a trim removal tool but a flathead screwdriver would work as well, just be sure not to gouge or damage the boss area. The factory plug has multiple ridges on it to keep it seated so it might take some working. After a good pry with my trim tool the entire plug shot into orbit in one motion. Now the fun part. Getting the tube to drop down just right can be tricky, especially as there are a few wires to dodge on the way down. I found that angling the fill tube towards the driver side and twisting as it went down from the top was the best way. Avoid jamming the tube with force that could bend it, tear the heat blanket on the firewall, or sever an existing wire. Use patience (and a step stool) and you'll get it. Once you've got the tube down, grab your seal/grommet and give it a light coat of Dexron VI ATF to ease installation. Now take the seal/grommet and slide it on to the dipstick tube. Move the tube over to the boss and slide it in, making sure that you have achieved a full contact/seal with the transmission. A cellphone or mirror can help here. Align the tube bracket slot with the extended stud from the transmission bellhousing. Using one hand to give some downward pressure on the tube, work a M8-1.25 flange nut onto the stud. My local parts house was out of flange nuts so I used a lock washer, flat washer, and nut combo. Keep downward pressure on the tube while you tighten with the 13mm deep socket. Reinstall the heat shield that was removed previously. Almost done! Grab your dipstick and give it a light lube around the seal area with Dexron VI... ...and send it home! Now as far as a proper hot check, I've always used a minimum transmission temperature of 145'F. The GM check procedure for these trucks says 86'F-122'F, but that's using the inane check plug thingy on the back of the transmission pan. Previous to that design, the hot check temp for Dexron VI was always 145'F min to 190'F max (ATF expands with heat). Perhaps there is someone out there with a service manual for a 2019 and can verify, but there you go folks. This truck should have had one of these sticks from the factory, and we HD users can debate with the non-believers (they do exist) why below or in different threads, but luckily we have a factory fit solution using original GM parts with about ~$60 bucks and some elbow grease! Special thanks to @64BAwagon for doing the leg work on the part numbers and the initial install. I found his thread (on a diesel site) while pondering if this was possible and his previous work made it a breeze. Get to dippin!

Turns out it is a M8-1.25. A flange nut like on the rear of the heat shield would work great but I used a lock & flat washer and a nut combo as Home Depot was out of flange nuts. Dipstick install thread:

It has been verified that a tube & stick from a 2019 HD with the 6L90 is a direct fit. Just waiting on my seal to install the assembly. Part numbers as follows: Dipstick tube: 24265546 Dipstick: 24271875 Seal (grommet to seal tube to trans): 15796802 I'll make a write up for this site when my seal comes in. There's a thread over at the dieselplace but it gets even less traffic than this place for obvious reasons (don't think GM gas HD owners would think dieselplace for info).

Those Ranchos are trash. Wait for the Multimatic DSSV part number from the 2024 HD ZR2 and ride in luxury.

Took it to Chevy and because of GMs lack of planning and terrible supply chain I suppose all the techs (the few they have because they are probably still paying garbage piece rate and can't find anyone.....shocker) are so tied up they wanted a next day appointment. I don't have time off to waste so frivolously so I went to GMC and got the same spiel. Both service advisors acted like the issue was new information to them so I knew what was coming. "Tech couldn't replicate issue....blah blah". Especially since all the way there it was acting like a prince. I decided against wasting a valuable day off in the service bay for them to chase a squirrel. I'm at the point where it is what it is. Hopefully someone with more time to spare and a bone to pick figures it out and Chevy releases a TSB that I can specifically point to, or if it's going to fail, it does so before November 2027 when the warranty is up (won't hit 60k by then). Good luck but again, I think the issue is in the programming. Not exactly something a dealer can fix without an authorized and released TCM flash from the brass hats at GM.

I'll take mine in and inquire about Jayroc's success. I am sure it's adaptive/tuning related. If I had access to the ECM like I used to with my LSx cars I'm sure it could be massaged out.

Blatant: I'm in the Phoenix area. If it's "normal" I can deal. My only real concern with the issue is longevity and damage to the drivetrain. If it's just a drivability inconvenience, it is what it is. I don't mind the heavy duty nature of the way the truck is (squealy brakes, stiff ride), its all par for the course with an HD. I just don't want my front U-Joint giving out early, planets going out...etc because of it. If it can take it, than so be it.

Based on the storied history of the 6.0, used to 300,000mi in fleets around the US and routinely over 200,000mi in personal customers hands, added to the fact that it had a worse (lack of) internal catch system than the L8T the following can be surmised: If you change your oil at the first 500 miles, and every 3,000 after and use a catch can, your engine will last 250,000+mi If you change your oil at 7,500 or the OLM warning, and don't use a catch can, your engine will only last 250,000+mi. You also probably won't be one of the 5% of people that keep the truck that long. All y'all are keeping it mighty nice for the second and third owners.

You sure it has the old pill? My November 2021 built 22 has "70c" stamped on it. I thought all new 2020+ 6L90Es with thermos were the new 158F pills.

I wouldn't be surprised if GM retuned it to be super aggressive after the crap showing in 2020 on TFL's Ike Gauntlet. The truck barely downshifted at all for them. My 2022 will drop gears like a professional trucker trying to brake an 80,000lb load (not a complaint, works great).

I've seen a few threads here dating back to 2021 and there's plenty of people on FB with the issue but has anyone inquired with a dealer or higher up the 2-1 clunk with the 6L90E (6-speed) trucks? It's intermittent. Doesn't do it all the time. First 5,000 or so miles, shifts like butter. Now almost (again, intermittent but more often than not) I slow to a stop the truck dumps into first gear and CLUNK. Sometimes it's rough enough to jolt the truck and jostle loose items around. Based on the intermittent nature and when it's doing it (usually coasting to a stop between 5-15MPH) I'd say its a tuning issue. Second gear is a 2.360:1 ratio and is more than capable of coasting to a stop, and even taking back off right away at part throttle. There is no need for the truck to DUMP into a 4.030:1 first gear without a load pushing on it as if it's trying to brake a 18,000lb trailer. That's what Tow/Haul is supposed to be for. I could expect the trans to command first slowing to a stop at 10mph if it was in tow/haul and the truck felt a push on the back sensors. There's no need to be dropping it into first gear at running speed hauling sail boat fuel. The tuning should coast second all the way until a stop, then select first at rest, or upon more than 40% throttle if transitioning from slowing back to take off. Maybe if enough people voice their concern the new "GM Customer Service" rep on this board can inquire. Again, if you ask me it's a simple tuning flash TSB fix and not some complicated mechanical warranty nightmare for them. Thoughts? (My truck is a 2022 BTW, November 2021 build)

My 22 started doing this a few days ago at ~4500 miles. Never noticed it before, but it dives pretty hard into first out of second now and an audible clunk is heard as presumably the driveshaft slacks from the hit. I am wondering if it's related to trans learning. It has smooth shifts from 1-6 and from 6-2. Slow speed coming to a stop is when it dumps into first and clunks. It's not overly aggressive yet but as mentioned you can hear it and feel it. My only other thoughts as to why could be a stuck accumulator or some other mechanical valve body malfunction.

Print the TSB out and bring it to them. They will source all the parts. Alternatively, find another dealer or bring it to a Chevrolet dealer if yours won't deal.

I don't think there's such a thing as comfortable towing with a 4.3L in the Sierras. At the weight you are talking about the truck chassis will handle it but the engine is going to be getting it's arse handed to it, especially with a good head wind on a travel trailer. Thing is, it's a once or twice trip. It won't hurt it long term and it will just be annoying while on the trip. Doesn't sound worth it to go and buy a new rig, in these times, just for a smoother pull over a collective 30 or so hours both ways.

Lots of "mirror covers" here. Looks like they have upper and lower and depend on whether you have power extend or not...etc: https://www.gmpartsdirect.com/v-2021-chevrolet-silverado-2500-hd--lt--6-6l-v8-gas/body--outside-mirrors

My 22 2500 HD LT backup cam is a potato.

I have seen on FB where people with non-Flex, standard gates have the dropping issue. A few reported it's due to the little drain holes in the upper trim that let water short out the switch that's directly below it. I also noticed someone posted a pic of thier 2020 and it didn't have the indentation at the top of the gate. Also seems like most having issues are 21+ where the Flex gate became an option. Is the indentation part of the multiflex and they are just using the same tailgate cap, but with nothing in there? In that case they don't want water to pool and put the holes? Or possibly the holes (shaped like triangles) are to snap something in place related to that gate? Either way, I used some clear silicone to seal them up. Rained today. Sure enough water pooled in the pocket so the silicone sealed it. Much preferred to the water dripping down directly on the switch/electronics. So, if it's related to gate drops, sealing the holes or buying and putting on a non-indented/pocketed gate cap might be the resolution.

Read between all the lines of this thread and you'll find if you're the average home owner/truck guy not needing to tow more than 10,000lbs with a travel trailer or dump trailer/equipment trailer then the L8T/6L90 is the most reliable and satisfactory combo you can buy in a modern truck today. .....and as one of those people that warms my heart.

I don't see the last few replies being hard to believe considering 3500-4000 is the classic SBC torque sweet spot. The engine was designed to sing here. Further, I don't understand why this engine would specifically have cooling issues (heat rejection) over any other SBC considering it has a better internal cooling design than the LSx series and that the radiator and cooling surface area of the 20+ HD is the largest it has ever been. The engine also has a monster clutch fan. If anything is hurting the cooling performance of these trucks I would look right to GMs thermostat setting and clutch fan engagement strategy. Member when (some of us) said 195+ thermostat in the trans was too hot for the K2s? Member? Member when GM just recently said "uh, yeah it turned out you end users who were deleting the thermo were right, retrofit this new on that opens at 158 in there instead"? I member. Don't put it past them to mess up their "calibrations" once in awhile.

On the big 2019+ T1 FB group someone posted a thread asking about who's had problems with the 6.2/10 combo in the 1500s. I was surprised to see so many transmission complaints. The common ones seemed to be 1) Back window leaks (unrelated but still reported). 2) Lifters (well known issue) and 3) 10 speed trans issues with quite a few replacements. Careful what you wish for.

So do I. Obvious cost saving to GM not to have to make a different set-up. The fake scoop is dumb but the big plastic vent, Star Wars ship design blocks, whatever the hell they are supposed to be things up by the cowl are ridiculous to look at and even distracting from the driver perspective. The only reason I won't bother to change them, dress them, or anything else is I'm at peace with the fact that my truck is the ugliest vehicle on the road and there's no point trying to polish a turd. It drives great, and I love the features/interior/capability...etc but its ugly and, well, that's that. Just wish I didn't have to be reminded of it when I'm inside of it by that stupid black block of plastic in my face in front of the wheel.

I wouldn't be surprised to see it in LTZ or higher trims, or maybe even a stand alone option for LT, perhaps included with LT. Reason being is the 6L90E is the bulletproof fleet trans on the market. I had time to wait for this truck but pushed on this year specifically to get the 6L90. Probably sounds silly to those who want the latest and greatest, but I only see the 10-speed increasing city MPG and that's about it. This L8T is great but it's not a 1,000lb/ft @ 2,000RPM monster. Being a traditional pushrod SBC it gets its torque meat and potatoes up at 3-4k with the HP starting to jam in good around 5k. I can't see shifting it out a bazillion times as its hooked to a heavy load really being beneficial. The 6L90E is perfectly matched to this combo to keep it where it needs to be (maybe some 4.10s for those that really want to sweeten the pot). It's ridiculously butter smooth and damn near indestructible (with a stock truck). Yeah, I don't really need/want the added complexity of the 10-speed just to keep up with the multi-gear Jones' and get another city MPG...

Anyone seen this part on the Chevrolet accessories page? LINK Just looks like a chrome fake vent for trucks that are sub LT trim right? But then in the FAQ: "Q: Will this louvered hood air vent benefit my vehicle? A: Yes, it will help with air flow in order to cool the engine compartment." Wait, what? Is this thing open? I figured it was just a standard LT fake vent. I despise fake vents. As much as it wouldn't do a lick of anything and certainly not enough to "cool" a stock L8T, it might make stomaching the fake vent easier...

Maybe for low speed and around town, but look up the gear ratio of 5-6 in the 6L90 vs 7-8-9 in the 10 speed. At highway speeds nothing will change. It's a big reason why TFL out MPG'd a 10-speed Duramax with a 6-speed Cummins on the Ike and the Flats. The 6-speed is matched very well to the L8T. More gears for the sake of more gears may leave people disappointed in their expected result. As far as "if you are towing all the time get a diesel" mantra, I would argue that when I was in my RAM diesel group I saw countless posts from hotshotters and guys that work their trucks daily for money that had no pay/down time due to the fragility of modern diesel emissions. There is a case to be made that if you need to pull to make money, you're at high risk of a minor problem (like a DEF sensor) putting you out of business for the day/week/month/who knows. I see the same thing with Class 8 rigs at the City or even my buddies brand new $750,000 concrete pump. Not even 100 miles on it and it's down. Oh, the pump part works fine. It's got diesel emissions issues. Anyway, good story. Cheers. EDIT: On the topic of low traffic in the forum, that's a sign of the times for sure but part of me wonders if its this website design. It is PACKED full of ads like its a clickbait tabloid site or something. You have to scroll a mile just to get to the first post! I get that this place doesn't run for free and that they need to make money, but this is really off the deep end. I'm sure it discourages new posters from sticking around. I don't remember it being like this a few years ago. It's really off-putting. I get the response is "put an ad-blocker in". No thanks. I don't have this problem with pretty much the rest of the entire Internet lol. Don't need another spy tracker following me around and copying everything I type into a database. Anyhoo....

This is what my 2022 6L90E stat looks like on my 11/21 built 2500 HD. The 70 stamp and all. I saw somewhere back that the HDs didn't used to have a stat. Guess what...