swervin36

I have taken my truck in twice to have it looked at for what I consider excessive DEF usage. My truck is a 2021 Denali that was a dealer demo that I bought with 3200 miles on it. The truck now has 11k miles on it and I have had to add 10gal of DEF. I asked the service person what was considered "Normal" DEF usage. The service rep stated that my usage was considered normal. When I asked what was considered excessive, he stated that he didn't know. Little more background. I have yet to tow anything with the truck. Most of my driving is back and forth to work with one trip from Colorado to Alabama. From what I have read on these forums, my usage would be considered normal if I was towing, which is understandable, but is this acceptable under normal conditions? Thanks in advance for the help.

I bought mine last May, it now has 16500 on it with no issues. I have to agree with MPX1. 1/2 Ton trucks are daily drivers and grocery getters. Time will tell but I love this truck.

After reading some of the post, thought I would share. Most of the time I do my own maintenance on my cars and bikes. There have been times that I have used some of the local quick oil change places. I had a Nissan Altima that only went to the local quick oil change place because it was getting the oil changed monthly due to the amount of miles I was putting on the car. Now I go to the local Auto Hobby Shop on base. They have a lift and I do not have to worry about disposing of the waste oil. The bay rental is only 6.00 which to me is a small price to pay not to have to crawl under the truck. I like being able to get a good look at the bottom of the truck to see if there are any other issues.

Every time I get in and start the truck, it adjust the ringer volume on my IPhone. Does anyone know of a setting in the radio or the phone that will stop this. Thanks in advance.

I have never owned a 6.2l but have had several 5.3's in Chevy and GMC trucks. The 5.3 is a great engine and pretty good fuel economy, if you can keep your foot out of it...LOL The first time I test drove a 3.0l I wanted one. Tons more get up and go then the 5.3 add that to the fuel economy and it's a win/win for me. My last 5.3 would average about 15-16 for my 20 mile commute to work. The 3.0 is getting 21-23. I did the math and even if diesel is .25 more per gallon, I'm still saving money. I know they are a new motor and as with any first generation they are still trying to get the bugs worked out but so far so good. Love the truck.

I took my truck in about 3 weeks ago to get the exhaust sensor replaced, and a couple of other issues. Since I got the truck back, I can't remember the truck shutting off. It used to do it at a couple of redlights on the way to work or when sitting in the drive thru. Don't know if I need to take the truck back or just let it go.

Mine has been averaging about 1 bar per 500 miles. On my last trip from Alabama back to Colorado, I saw it do the two bar sudden drop. If the gauge reads 1/2 or less, it will take a full 2.5 gal jug. I was waiting and waiting for it to drop, then boom not one but two bars.

As of today 6100. Love the power and the growl of the motor, it sounds like a truck....LOL. Least favorite, sensor issue and now problems with the navigation system. Should be scheduling an appointment with the dealer first of next week. Almost forgot, love the MPG!!! Average is about 7MPG over my last 5.3.

It was the opposite with my 18 5.3. The DIC always showed about .5 - 1 mile better than the hand cal.

Funny thing, I drove the truck to Alabama from Colorado on vacation. Light went out about 2 days before I left. When I got back and the truck was down to under 1/2 tank the light came back on. I filled up yesterday and this morning no light. Wierd.

I would say a big yes. I am having the same issue with my GMC 3.0 and was told the same thing a month ago. Except the part about limiting my driving, I was told the truck was safe to drive. It is a shortage of parts across the board. I had a small accident while on vacation in Alabama which took out my drivers side mirror. No one in the country has the assembly and I have been waiting two weeks for the mirror assembly and the drivers side window glass with no expected delivery date.

Is the Mobil 1 oil available yet?

I would take it in any way to get it checked out. Light went out then came back on after I got back from a 2800 mile trip, it's still on. I called OnStar and it was the same code as before P1488 I believe. Gonna call the dealer today so see if there is any update on the parts.

I have not had the opportunity to tow with it yet but so far yes. I have owned several 5.3's and have driven a 6.6 Duramax for work. The 5.3's are great engines but even the latest generation feels a little sluggish pulling off the line unless you really mash on the gas. The 3.0 you can really tell the difference. I thought there might be some issues when passing but have been well pleased.

Me too. I was expecting closer to 27-30 for the trip. Especially after passing Ok City on the trip out. Now I do have a lead foot and had the cruise set at 80 for most of the trip. If I had kept it at 75 or below that would have probably gotten me into the 27 range. Still pretty impressed with the mileage I did get. I have also made a few trips to Denver and seen a 30 mpg average.

I usually make a trip from Colorado to Alabama in March-April to do some fishing and help my mother do some stuff around the house. This year I had to wait till July due to everything going on. To say the least I was very pleased with how the truck performed on the trip. I like to take the southern route cutting down through New Mexico and picking up I-40 in Amarillo. Last year I made the same trip in a 18 Crew Cab 4wd Sierra with a 5.3. For that trip the MPG going out was about 18-21. On the return after passing Oklahoma City, I had a head wind and best the truck would do was about 16. With the Baby Duramax the trip average was 22-24. I was easily able to go over 500 miles between fillups. With a little prior planning I was also able to find diesel between 1.99-2.09 a gal. Total trip was 3100 miles and DEF usage was 2.5 gal.

Ditto. Got the first one at about 1500 miles, did the firmware update. Got the second about 700 miles later. They said it was a bad sensor and they were on backorder. Funny thing is a couple of days later the light went out.

Just had my check engine light come on again. OnStar diag came back with the same code P1488. The truck has already been back to the dealer for this about 500 miles ago. They said that there was a firmware update that they installed and it should fix the issue. Well I guess it didn't. I have an appointment in the morning to get the truck looked at.

I had this happen once about 2-300 miles ago. Was moving a bed and saw the temp creep up close to the 230 mark. Then after a mile or so, it went back down to it's normal just a tick over 210. I have been watching the gauge to see if it would do it again but so far so good.

I have been wanting a diesel for years. Since I only occasionally tow a motorcycle trailer with 2 Harley's it was a hard to justify a 2500. When the 3.0 finally came out in the 1500's I went and test drove one and really liked it. More power than my previous 5.3's and better MPG's. I went truck hunting and had found a Chevy RST with a 3.0. Before I pulled the trigger, I went to a couple of other dealerships to see what I could get. I settled on a GMC SLT with the premium 2 package. It had everything that I wanted. 3.0, 4wd, heated/cooled seats, nav, and front and rear parking sensors and factory running boards. I have put about 1600 miles on the truck so far and like the truck better each day. Back and forth to work I average about 21 MPG, on the highway is a little over 30. I know it won't last but in my area, diesel is .30 to .40 cents cheaper than regular gas.

With my 5.3's they took 8qts. I would always buy the two 5qt jugs of Mobil 1 which would run 50-55.00 plus filter. I just did an oil change on the 3.0 at about 1500miles probably not necessary but did it any way. Picked up 8qts, filter and 2.5gal of DEF out the door for 75.00. Without the DEF the total would have been right at 60.00. Which is pretty close to what I was spending on my 5.3's. Since the oil is hard to find, I decided to get an extra quart, just in case.

I have had several 5.3's over the years. I just picked up the GMC Sierra version of the Baby Duramax AND love it. I first started looking at diesels about 5 years ago when I was making regular trips between Scranton PA and Central AL. The 2500HD's are great trucks but I could not justify it, my occasional towing consists of 2 Harleys on a flat bed trailer about 4000lbs. The 5.3 is more than capable of pulling the load at highway speeds. I test drove one and was surprised how much more responsive the truck was. I have put about 1100 miles on the truck and am averaging 21-22 mpg for my daily commute. Drove to Denver today to see the grand baby and round trip on the highway was just over 32 mpg, by the DIC. So far loving the TQ and the MPG.