Chuck FB

What it did from what you describe sounds a lot like what was happening to the earlier years of the very similar transmission in the Duramax version, out of nowhere it would slam into second gear and I believe then that the repair was to replace the valve body. There was that software that came out which was supposed to sense if certain parameters were not being met and warn the driver that there could be an issue happening in the future but that was not a fix. There were some changes somewhere along the way with the valve bodies but when and how well they have panned out I don't know. The ten speed in the Duramax was out since 2020 so its had a lot more use history vs the gas version. Keep us posted to what GM decides to do with it to rectify the issue.

That is the funnel kit I bought and for being here in Canada I did get a better deal than what other sources were charging through a certain supplier in town that sources more directly and they ordered it for me. There are other items now on the market which would be perfect as well but this has worked well which was the hope when I bought it. I mentioned the Amsoil quart bottles as they have that squarish shape up top and it props nicely on the rim of the opening without falling into the funnel so I can leave them sit and drip a bit. You may have already figured out that to get the cap off the valve cover unless one is 7 + feet tall its not going to be reached without standing on a step of some sort and so when I do that I put the right adapter in and just leave the elbow on the funnel all the time anyway and open the lid and then if using quart containers for sure I can stand beside the truck and leisurely add the oil, and I can leave that funnel on when starting the engine to let it idle to fill the filter and then add the rest of the oil to top it up before removing the funnel and putting the factory cap back on. I put the cap back on the top and slide the bottom cap on as it fits onto the elbow adapter also and then store the funnel in a clean household plastic garbage bag along with the adapter so I have no reason to be washing out the inside of the funnel as I keep it completely clean between uses. Draining the oil as per the under the truck portion, yes indeed that is slick as someone was thinking on GM's part there and admittedly I don't drop the oil screaming hot in this truck due to the exhaust being there and makes it safer as far as the oil temp if its just warmed up some instead as I don't have the truck on any ramps etc as I do it as the tires sit on the garage floor. The filter is not boiling hot then either and can drop it off into another pail after pulling the drain plug and just leave it drip out. Go back under a few hours later with new filter in hand and clean off the filter base and put the new filter on and install the drain plug. The filter is a little cramped in there as per wrapping ones hand around the filter and I am so used to using the band style filter removal tool that its no big deal and same for snugging it up. My filter wrench is many years old now but I think this is the current version and sounds like the right size, just in case my explanation was not great ( those nylon strap wrenches that one tool fits all filters are not my favorite tool to use, I much prefer this style personally ) 57020 Swivel Gripper - No Slip Filter Wrench - Small | Lisle Corporation And again about the oil draining and filter setup under these GM trucks, I've watched Ford videos of them struggling with oil flying sideways out of the oil pan on the gas 7.3 due to the sideways drain plug onto other components or cross members and guys trying to make shields out of carboard etc and other Ford pickups that Ford insisted they have sideways drain plugs. One win for GM there anyway with this engine.

Thanks for that, yes just because I could I measured what came out just to give me some guidance although I already knew to expect it to take at least 9.5 to just throwing in the whole 10 quarts off the shot and doing a one and done heat cycle to drop out the excess to get to the proper level. I don't recall exactly now what I measured that came out but was less than I put back in, I knew I spilled some on the garage floor but the main part was that I was thrilled in the discovery I did not have to touch my exhaust to flex it down. The gasket manipulating is a pain of course to create that clearance to take the pan out and put back in but its all very doable if one is careful and not forcing the gasket to flex too much. From the quote I got at a transmission shop of 900.00 here in Canada ( never asked at the dealer what they charge ) I saved 700.00 doing it myself after paying for the supplies so that to me paid very good wages !, and I knew what fluid was put in and that I had changed the filter and that the level is correct without any doubts.

Typically its said and I agree so far that the engine oil drain plug oring is not required to be changed out unless you see some damage happening to the oring as apparently the oring lasts well. The dealer I have been getting a few parts from never even stocked the oring but instead stocked the whole drain plug that comes with a new oring which for the dealer is easier because they just throw in a new drain plug if there was any question about damage on it as well and charge the customer accordingly but again only if it is needed. Also a hint about the drain plug oring to help it last vs a risk of causing damage to it, after its been removed and wiped off or washed off ( that is a whole other topic about some solvents damaging orings because some solvent types do ) to make sure to relube the oring with a bit of new oil so that it won't "grip" on the sealing surface of the pan and needlessly stress out the oring. Its no different than putting some oil on the sealing ring of the engine oil filter. So I just grabbed a new drain plug to have on hand although more recently bought just the oring as well but as its special it costs half the price of the drain plug ... ! Since you mentioned the hate to be empty handed theme, I am not sure what you have in the way of filter removal tools as I like using the exact sized for the filter steel 1" wide band with side to side swivel handle filter removal tool, and it can be used to snug up the filter without risk of damaging a filter as well ( its probably a lisle brand I have ). The drain plug hex size is 15mm and I always like using a 6 point socket if I have a choice and with this truck I've been using just a 3/8 ratchet that has a fairly long handle. Do you have a funnel that will work to pour oil in as that is definitely the short coming bastard part about the design with that fill port on the valve cover on such an angle that no normal funnel will even work. There are adapters and things on the market that will set into or screw into that fill port, I didn't want to deal with US shipping as that is all I was seeing at the time so caved and bought a Lisle brand multi vehicle fit adapter funnel kit and it really works well but there are much less expensive adapters out there that work in conjunction with an off the shelf funnel that would do the job also. Now that I have it, I like how it works and works so slick with the shape of the Amsoil 1 quart containers I have now switched over to. Whatever you do, have a funnel system of some sort as you will be swearing if you dropped the oil and then realize you have nothing to properly pour new oil in without spilling it all over the engine !. Other comments, quite a bit of oil flows out down the filter when its cracked loose due to the housing above the filter so let it dribble down the filter until it slacks off flow and then remove the filter to create less possible mess. It seems these engines can sit for quite a while and drip and if you have time let it sit there and drip out of the engine as much as it wants. Also a good time to grease the 9 zerks on the front end, that's my typical practice anyway to grease the suspension and steering each time I change the oil. And remember to reset the oil change minder ( not something I am used to doing with older vehicles and equipment ).

I can't say I have ever heard of someone getting that type of mileage out of a set of tires even though they rotated on a regular basis but without a doubt if the front end gets wear and those tires are no longer able to track straight it scrubs them off, and driving style and road surface make a huge difference as well. However that is not what prompted me to comment as it was the new tire theme of sitting in storage waiting to be used scenario. I am sure some tires can last for quite a while in storage if its not too warm and out of the sunlight but unfortunately some tires the way they their rubber compound is formulated they can age and dry out even in a reasonably decent storage location. My brother ran into this maybe three years ago when he was looking at the tires that were on his dually truck and a combination of wear on the rear ones and noticing that the front tires had some cracks around the sidewall of the tire not far from the bead but he had replaced only the front ones not long ago with 2 of the remaining 6 he had left from the initial two sets of takeoffs he had all bought at the same time .... 10 years ago ! ( the years fly by, a truck that only gets used a bit to haul a camper during the summer and sits in a shed for a large part of the year ). That second set of 6 tires, two he had put on the front prior like I said and they had very little wear but those cracks were now present. So we go into the shed where the other 4 tires had been stored all this time and every one of them had the same cracks in the sidewalls and so in the end it amounted to throwing away 6 brand new but 10 year old takeoff tires into the dump that he got a deal on at a tire shop because they aged out. They were a Ford factory equipment BFG tire and those tires did not age well compared to some tires I've seen far older then that and did not show that type of aging. True, they always say up here anyway that 7 years is sort of a limit for age by rights, we don't have the intense prolonged heat that many of you have down in the states that just cook tires and depends on where the vehicle sits when not in use. GB, another words maybe had you bought a set of tires to store it would have been fine as long as you used them up fast enough but there are no guarantees when it comes to rubber, tires or of that other type stored in some guys wallets

I am curious as to how much fluid you put back in the transmission ( assuming you had replaced the filter to compare to my findings ) and then went through the process of warming up the trans before pulling the check plug to drain out the excess and if you measured how much came back out. I just found it surprising that some claimed a certain amount less fluid being put in and then draining some back out. The attitude of the truck as per if the surface is level and how the trucks stance is would make quite a difference since the check plug is right at the front of the transmission.

Gasbuddy lists Costco in Mansfield as the cheapest in Texas at 2.93 for regular but also more than one place around that 3.00 level in Houston. I am guessing that is probably some of the lowest fuel prices in the states ?

A little girl said her prayers every night before bed and she asked G d to watch after each person she loved. One night she forgot to pray for her babysitter and her babysitter died. A few days later she forgot to pray for someone else and they died. The next night she forgot to pray for her dad. The next morning her dad was terrified. A bus almost crashed into him. He almost fell off a fifty foot ladder and almost wrecked on the way home. When he arrived home, he said I had a terrible day. His wife replied, “You think you had a bad day? My aerobics teacher died during class.

Depending on what vintage of Jeep you have, you may have a new enough one that its an open element filter and with little effort pretty easy to examine or if older its a canister and cut it open. It would be interesting to see what if anything shows up on the filter media. What blows me away is watching some of these videos where the person says they are on the 4th oil change with R&P and there are still all sorts of pieces that look like flakes of build up that broke off inside the engine along with smaller particles layering up in the lower part of the filter pleats and the person is saying it looks a lot better than the first filters did ... like holy hell ! LOL. I wish I could get my hands on HPL if I ever chose to try it out but that seems to be a no go here in Canada, I am only guessing that the product gets sucked up so quick in the states that they have no reason to even contemplate having dealers and shipping to another country and all the bs associated with that.

So if I catch that correctly, really there are limited options to use that have the ability to reverse a mess created from too long of an OCI by using Wally World oils. Valvoline R&P being one and as of yet to be proven in real world use with the Mobil Clean. Doesn't HPL have a solution they offer as well as an additive to other oils or a certain oil type that is used as a whole to do a similar job to R&P ?

Uh yes, that's the name of the package. It doesn't quite bring it up to 1 ton specs unfortunately and imagine they have to do that for a numbers reason rather than a physical one. Am I correct though that the Max Trailer Package and therefore the 12" rear is only available on the Duramax and not on any of the L8T 3/4 ton trucks ( and that the same 11.5 rear axle center section is used on the 3/4, 1 ton SRW and even 1 ton dually gas version ) ? I'd also be curious to know if the wheel bearings are the same on a SRW configuration between an 11.5 vs the 12" diff as I assume parts would show that up but may not explain what the difference is if indeed there was a physical difference.

I just can't think of the exact term GM uses for that higher gvw package without looking at the website but basically sort of a trailering package and I imagine it may also have been created to skirt around the licensing fee differences between a3/4 and 1 ton that apply in some states although ironically I believe in some states its the reverse that a 1 ton is the cheaper truck to license over a 3/4 ton. It makes no difference here in Alberta but oddly enough a 1 ton through my insurance company is a bit cheaper to insure over a 3/4 ton as its based on the insurance statistics they generate. For sure when ever you do have the chance to weigh your truck and to be fair, try to have the fuel tank full or nearly so rather than give yourself a false sense of the truck being lighter by having an almost empty tank. In my other comment I was mentioning stock sized tires and partly in case someone was reading this and thinking they could lower their pressure down to what your aftermarket tires are able to do with your empty truck as that is a vastly different picture in the leeway you have to play with for running minimum pressures while remaining safe. I will say also that its easy to see from reactions of truck owners that may have been more used to owning a half ton in the past or a car and be it on a forum like this or in person etc that they get so wrapped up in that placard pressure sticker that they can't get their head wrapped around the fact that an HD truck due to how much it can carry can also vary the tire pressures drastically lower than those pressures ( typically more so for the rear axle on stock sized tires ) when empty vs some car that isn't made to carry much so the tire pressures can't be lowered since it needs almost that much pressure just to carry the empty car. If I ever do find myself in the states with this truck, I will only be too happy to switch it over to the US measuring system as then I will understand all the dash readings. The only thing that is off for me slightly with US measurements is US miles per gallon as I grew up with the Imperial gallon and to this day up here anyway speak in Imperial miles per gallon ( I don't do that on this forum though as that would confuse everyone for no good reason ).

You must have that upgraded gvw package which is only available or at least was in 2025 with the diesel engine for the 3/4 ton and that gave the truck physically the larger 12.0 ring gear rear diff and the 3500 rear spring pack. There is a difference in what the diff housing looks like externally as one tell tale and also your truck should have the upper overload spring pack and the frame pads that the pack goes up against. The pressure the tpms system kicks the alarm in on a stock setting truck, that is a good question and was just from what I recall but I doubt I made any notes on it as I knew for the rear that it was not at all what I was after regardless either. Being that you have a diesel and if running on stock tires the minimum pressure on an empty truck seems to be around 50 psi from hearing of those that have weighted the front axle but the rear axle is very similar in weight to a gas truck and again a near empty truck on the rear could go down to 35 pounds at minimum. However the weigh scale is the proper way to know for sure as a guide. As to changing the readings on the dash from metric to the US measuring system, oh yes that is done easily but what I was attempting to explain was that I can't pick and choose items I want to have in US and those I still want in the metric system at the same time as its either all or none. For example lets say you drove into Canada and switched your dash over to metric so your speedometer read in km an hour, well then your reading kilopascals on your tpms readout and your wife looks over and says what the hell is that saying in the tpms screen and you say "darned if I know, I think its Chinese" !

This is partly why I decided to have switched over to Amsoil SS as a way of hopefully preventing the buildup of the sludge/carbon on the pistons and clogging of the oil control rings and the carbon that would cause the compression rings to stick in their grooves as well as stay cleaner up top of the heads in the valve train in the first place, an oil that has tested better by third party testing over typical shelf oil and also doing my best to run relatively short OCI. However in saying that I don't think there is any way to easily prove the oil I was using prior allowed for a buildup at the OCI I was doing, nor in the other direction to make claims the Amsoil is keeping everything clean either. There really isn't a window into the engine is there to know anything for certain even if oil samples were taken for example that showed still healthy oil being dropped out of the oil pan other than engine tear downs that extensive and expensive testing of oils does to actually visually see what is really going on inside the engine. I wish there was some easy method of seeing what is going on but I don't happen to be aware of that if there is.

I will admit I haven't experimented much with pressure drops beyond the numbers I put in and part of that is that the numbers I used are fairly low and then found out it would trigger regardless at that 35 psi. Having said that I had tried before had changed the placard pressures and being that I have a 1 ton set to 80 on the placard for the rear I believe it triggered close to 60, the front I don't recall now for sure but thought maybe it could get close to 45 from that factory 60 placard pressure. So I never did figure out if it was a number of psi from placard pressure to the alarm or a percentage of the total placard number as some figured it was like a 25% drop from placard pressure would trigger it. So as to try and answer your question, I believe I set the placard pressure on the front to 47 or so and while I run the front tires at 40, they have dipped below that some if its colder and I haven't put "winter air" in yet and never once have had the front alarm go off. I would say that the answer your looking for is no, that if you set your placard pressure to 45, you have a certain amount of room to drop below that pressure before the alarm will go off. The pressures you decide to run in your truck, that ends up being what makes sense to you based on what your carrying in your truck or if towing, then have to bump them back up to something that will carry the load in the rear and the fronts typically left at the same pressure. It all comes down to that chart I put the link to and using an accurate roadside scale to be your guide, both unloaded and then loaded to know your minimum safe pressures. I just wish GM would allow a person to change the readings for the tire pressures to the English system of pounds as I have to look at that goofy metric reading that will never ever jive in my head and will go over and change it just to figure out what they are if need be and then change it back.

Glad that worked, and in this case that is all on Autel for somehow dropping the ball for not updating the GMC section properly. I believe in the basic section or unless it is in the advanced, when one does a check of lets say individual sensors for what the pressure is ( and it shows a temperature as well ) , I think it picks up on what the model number of the sensor is in a certain section where you choose "OE" sensor or at least mine is telling me what the model number is and matches to what they actually are and that is the number I quoted in a prior post. I don't recall now if I had said prior that I discovered with my truck anyway that no matter how low I set the placard pressure for the rear tires, if the physical pressure is under 35 psi and I drive it for about 15 miles the pressure warning will come on for one or both rear tires. I am speculating that there is something else in the trucks system that over rides the placard pressure setting once it drops below that minimum pressure to run a metric LT tire at. The weird thing is it does not trigger right away after driving a shorter distance, it took that longer drive for it to trigger. Just something to keep in mind if you were experimenting with pressures below 35 pounds for a tire designed for lower pressures ( larger than stock floatation series tires ) and not being overloaded of course.

True, hard to say what differences there may or may not be between Chev and GM as well as a production year or mid year part change either. I just found it odd that under the Sierra choice on the Autel that many of the last few years of production year did not include the choice of changing the tire pressure but if that is an Autel thing or a GM thing as to why the choices were not there. Knowing what tpms sensors are on the truck should give some guidance into which choices on the tool even make sense to try as I wouldn't give up just yet with the tool but I guess he will see what if anything he comes up with if he finds out a bit more info and tries a few more things on the Autel.

I forgot to answer the question as per what market mine is set to and yes I finally found that area on mine and yes its also set to America. So here's something I realized as I wasn't looking at that part in the Sierra section until now, your right that what I see here as choice 3 under Sierra which says 07/2023-06/2026 ( 433 MHz 13542523 ) it has no choice 5 for tire pressure selection. Where as it does under the Chev choice. However I kept going down the list within the Sierra and I am really wondering if choice 9 will work for your truck as it has the same model number and hertz sensor as my truck. I would say try that choice first, if that doesn't work then jump over to the Chev section and again choose that same model and hertz choice as for some reason the Chev section gives the choice 5 of tire type/pressure selection for going back a number of years. Could very well be an Autel thing that they just didn't get the updates all done properly under Sierra but anyway first try that selection 9 I suggested under Sierra and then go from there.

Ok I missed that part that yours is a GM. The strange part is that the choice for year ranges and within the year of 2026 is different on the Sierra then on the Chev for some reason as I am looking at my tool at the Sierra choices. Now I am guessing you see as to your sensor part number as it may be different on your truck for some reason and a call to GM should get you the part model number of the sensors you should have as well as which MHz your sensors are. I know mine are the ones as per what I listed but there are other choices in the Autel and got me wondering if by some chance they put different ones in your truck. Having said that, did you try using each of the choices starting from No 1 and going on down the list, not sure if that would mean shutting off the engine each time and resetting the tool and going at it again each time. Also I thought of something else which may sound retarded but if there was some stupid chance that the chev choice would work. The reason I say that is that the Sierra is showing a range up to 06/2026 for the various choices of sensors it could be where as the Chev has one choice that has that 12/2026. By the way it is possible to not run the truck and you may know that as per not pressing the brake but pressing and holding the start button for a few seconds and it lights up the dash ( its called service mode ) but that sucks battery power and if it were me doing it that way I would be throwing on a decent sized battery charger before doing it that way as killing your battery won't make you happy at me at all !. Like I say, just a thought to try the Chev choices if you have already exhausted the Sierra choices but first it would be nice to know for sure what exact sensor model and hertz your truck uses as I assume only those choices that mention the sensor would work unless a choice that does not mention the sensor model would somehow work. Its frustrating when one is trying to use tools like this without the experience of the tool and the vehicle, as I am sure dealer techs themselves struggle with it when starting out or a new model year comes along that is slightly different.

Its just that it worked on 2024 trucks on this forum and my 2025 model truck, unless GM did something since that point to screw up access or Autel has a bad update. I haven't had need to use my tool since last year when I did the changes to the placard pressure settings and since then I updated the software on my Autel but have not plugged into the OBD so hard to say if I would get a surprise as well. All I know last year when I bought the Autel I was warned to be sure to update it before I tried using the unit as they said who knows how long ago unit itself was actually manufactured as the software could be way out of date.

And so you had gone through the process of registering and updating the tool and so on ?. All I can say is that on the front page as the tool fires up you go to advanced mode, then vehicle model comes up and you choose Silverado ( not the DRW or EV since your a single rear wheel ) , then I think its choice 2 which is 07/2021 - 12/2026 ( 433mhz 13542523 ) as that is the series of tpms sensors and then go down to choice 5 which is tire type/pressure selection. Hit yes and it says to connect to OBD port and turn ignition on. Having said this, I updated the software in my tool lately and these year range choices look different from the past due to them doing some updates it would appear and I have not connected up to the OBD port since last year so hopefully I am not in for a surprise with them screwing up the software and that it won't work on my truck anymore either. So my question is, when you plugged into the OBD and started your truck it had that message on the Autel screen "vehicle not supported" ?. That does seem odd as tire shops would be pissed right off if hey can't use their tool on the model year after mine that in theory is supposed to be much the same truck ... unless GM did some change in the computer system to block certain things from access.

Same here, first I bought a few filters to get me going right after I bought my truck to do some short distance initial oil changes, then realized I could buy a case lot for less as they drop the price if filters or trans oil etc is bought by the un opened case lot as well as the discount for buying the vehicle there. So I have filters for a while but its good to know going forward, knowing to expect it to be a different part number and looking filter at the dealer and not be confused over it and think they are handing me the wrong part.

Which has made me wonder with the various engine failures of a few brands in the last few years, is it sub par materials such as lifters etc causing failures, or bearing clearances on the crank etc or perhaps bad designing of an engine physically or causing too much load on the components due to the hp/torque they can push out of them. Or is the oil viscosity and additive package of current oils or a lack of oil flow by an oil pump not able to supply sufficient oil at idle or under high load at low rpm. Or is it every item I listed that combined together has pushed the limits so far to the left that there is hardly a margin of safety left and add in some fuel dilution and too long of an OCI and premature engine failure is the result ?.

I trust you saw the other comment where he knew what he was talking about !. Yes, these darned newer vehicles with all their so smart they are stupid technology, goes and drains the battery down. As you might see my other comment, I installed a Noco 5 battery tender under the hood and at this point still have the cord routed so I have to lift the hood and then plug it in but am typically parked in a garage or a shed so its not risking the engine hood in the wind. That way I am assured or hopefully so of not finding I have a battery drawn down and can't even start the truck and that also damages the battery to draw it down too far.

I guess no surprise my guesses were wrong !, at least now I know if I ever happen to see it grayed out in my own truck as to what is going on. I never happened to catch my truck with it grayed out, it seemed every time I would test to see if there was an update it never found anything and yet more than once I would check to see if there was an update and there was nothing, then a day later or even that same morning I would drive to town and after more than one engine shut down in town as I did my errands it would pop up that there is an update now ready to install and the only place I have a connection to the internet is at home by wifi so its not as if it grabbed the download while driving. I don't trust these new vehicles due to all the crap they can decide to do while sitting for some days not running and run the battery down so most of the time if I know the truck will sit for a few days I plug in the battery tender I have mounted under the hood and so the only time the truck must have downloaded software was when it was sitting in the garage where the signal is awful but I have that tender plugged in and somehow it managed to download it. I honestly detest all this crap, way to easy to leave a person stranded. Since I don't trust any of it I don't do the install of the already downloaded software until I get home and sometimes have even sat in the truck to watch what its doing as its going through the process to its conclusion as its not like it is set up that it will tell you the next time you fire up the engine that the update that was initialed actually installed or installed properly. Yes I can go into the updates and see the list. After I go through the install where I feel its safe to do so in case it breaks down as a result, I will plug in the battery tender after the fact to recharge as I don't know how much power its taking just to do the install and that can take a while for it to install.