Another JR

Some service advisors are clue-free. Others seem to feel an obligation to deny knowledge of well known issues. Some are very good. I received a total runaround from my selling dealer regarding the TSB for the transmission cooler bypass valve set temperature change, but usually they are pretty good. I still can’t get an audio file to upload, and I am not going to set up a YouTube account for it. However, if your truck briefly sounds like a diesel for 1/4 to 1/2 second very shortly after it starts, that’s the oil pump priming issue. It occurs after extended shutdown because some oil drainback occurs creating an air gap in the pump intake path. It is normal, it occurs more in colder weather and with longer shutdown times.

Did you note the engine and transmission temperatures when this occurred? It could have been a high temperature protection mode. My other guess would be the 10 speed transmission valve body failure issues (hopefully not), but if temps were high while towing and it later returned to normal, it may have just been an overheat protection kicking in.

I took a 12 second video on my iphone but the file is too big to upload. I will have to figure out how to extract the audio or just do another start with an audio recording.

My plans changed today so I haven’t had a chance to record a start yet. This is one of the threads I recall, but you were involved so maybe you already reviewed this one:

Oil pump noise was discussed before. I will try to remember to record a remote start later this morning.

I don’t have detailed measurement data, but this past March we were hiking and camping in Death Valley and the Las Vegas area when this Spring’s heat wave hit with 105 plus temperatures and our 2021 L8T system kept our crew cab as cool as we wanted it (68F setting) with no trouble. Fan flows on auto once stabilized were fairly low. It seems like the OP’s system should be performing better.

Are you going to take long trips in it? If so, try out the seats in the various trims. For me the lower trim level seats were not comfortable.

I have had the same suspicion that some of these single use bolt installations are not actually torque to yield. In this case, the size involved and the initial torque, plus the additional rotation angle, don’t seem to be enough to be causing yield. However I have not done the actual calculations. One reason to use torque plus angle when not intending TTY is to reduce variation in the clamping force due to thread or head friction.

I have yet to see a set of GM wheels on a current generation HD truck (2020+) that I actually like. Least ugly is the best one can hope for in my opinion with the current GM wheels. The steel wheels actually look better than most of the alloys to me. Since they are the equivalent of work boots, I don’t let it bother me to the point where I consider spending money on wheels for the sake of looks. Luckily the 18” ones that came with my 2021 don’t scream ugly at me - they just whisper “can’t you at least notice how ugly I am once in a while.”

Is your truck not available for you to look? If not, can look at mine later this morning and post back. I suspect they are easily accessible.

Newdude posted while I was typing. If they didn’t have very good torque control with their impact driver or if they did the final quarter turn after applying 89 ft lbs, I agree with him they should be replaced.

Based on the service manual picture you posted, the four vertical bolts are single use and the torque specifications appear to be intended to be “torque to yield,” which permanently elongates the bolt. If they were torqued per that specification they should not be reused. However, if they used a properly limited impact device and only torqued them to the initial torque value of 89 ft lbs and did not do the final 70 to 80 degrees of additional rotation, they never yielded the bolts and they could be “reused” and torqued properly. The biggest issue in deciding whether to reuse them likely will be uncertainty over the torque applied by the impact driver.

Why the extreme lift?

The dealer I bought my truck from is actually pretty good. The problem is the labor force issues due to the dealer industry practices. They are struggling to keep experienced mechanics due to the pay structure, and the fluid change staff is minimum wage and uncertified. I still work with them when I need to, but I have had issues due to incompetence or lack of care as I described above. The unauthorized software update issue I suspect is driven by GM policy, but it is still an issue. It is my goddamn truck once i take delivery. You don’t modify it without my permission.