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Posted

I was wondering what most drivers leave the drive mode set at ?

I read the manual and know what it says, but what setting do most drivers have selected for daily driving. The choices are ....Auto, 2 hi, 4 hi, and 4 lo. 

Unless you are a rice farmer, I don't think many would say 4 lo, but how many leave it in Auto? Or is 2 hi best for highway and around town. Is it good to leave in 4 Auto ? Or is it less wear and tear to drive In 2 hi. It will be interesting to see what everyone has theirs set at. 

Posted

P.s. I have a 2020 Denali 4x4 6.2l and I mostly drive in 2 hi.

Posted

My long time service advisor has always told me not to use auto unless I'm off-road, even in the wet. Seems like it'd be OK on wet pavement, though. He says the front differential burns up easy.

Posted

2 Hi daily

Auto, In case wet roads could turn icy, Or I want to do a hard launch in the rain

4 Hi, Icy / Snowy / muddy conditions

4 Low, deep stuff and I'm trying not to get stuck

Posted
8 hours ago, SIXFOUR said:

I was wondering what most drivers leave the drive mode set at ?

I read the manual and know what it says, but what setting do most drivers have selected for daily driving. The choices are ....Auto, 2 hi, 4 hi, and 4 lo. 

Unless you are a rice farmer, I don't think many would say 4 lo, but how many leave it in Auto? Or is 2 hi best for highway and around town. Is it good to leave in 4 Auto ? Or is it less wear and tear to drive In 2 hi. It will be interesting to see what everyone has theirs set at. 

 

 

Those aren't drive modes.  Those are transfer case modes.  

 

Drive modes are in the twist knob that has tow/haul mode.  Depending on truck there is Tow/Haul, Normal, Sport, Off Road and Terrain mode.  ZR2 will have Baja IIRC.  

 

I use Normal or Sport daily.  

 

As for transfer case, 2HI all the time unless its winter then its 2HI when dry, AUTO when its getting interesting and 4HI if the roads are unplowed.  

  • Like 1
Posted

2H all the time unless we get heavy snow which is rare then 4H also will put in 4H on a straight road about once a month just to exercise the 4wd but take it out before I have to make a turn. 4auto when I feel like messing with it in a heavy downpour. 

Posted

In Montana - you know, 3 degrees north of freezing to death - 2H unless there is ice / packed snow on the road and then Auto
Sport all the time. I LOVE the 6.2 exhaust 

Posted

Thanks for the correction on transfer case modes. 

In drive mode "sport" does it return to normal once the engine has been turned off then on again?  

I also run in 2 hi for normal highway driving and use auto when ice, snow or rain. 4 wheel only off road or mud. That is a excellent suggestion to  exercise the 4 wheel mode every so often, for me I don't use it very much and engaging will keep it turning and lubrication of moving parts.

Thanks

Posted
7 minutes ago, SIXFOUR said:

Thanks for the correction on transfer case modes. 

In drive mode "sport" does it return to normal once the engine has been turned off then on again?  

I also run in 2 hi for normal highway driving and use auto when ice, snow or rain. 4 wheel only off road or mud. That is a excellent suggestion to  exercise the 4 wheel mode every so often, for me I don't use it very much and engaging will keep it turning and lubrication of moving parts.

Thanks

 

 

IMO, AUTO in rain isn't necessary but to each their own.  

 

You do have to engage Sport each time you drive, yes.  The only exception so far is Silverado/Sierra 2024 and newer with the 6.2 as they now have the dual mode exhaust.  If you switch to Sport to open the exhaust up louder, it will stay in Sport each ignition cycle until you change it back.  

  • Thanks 1
Posted

IIRC,  tow/haul mode will stay active for up to 4 hours when shut off. 

 

Not sure when this was feature was added. 

Start of T1's?

 

Posted (edited)
On 4/1/2025 at 3:31 PM, taze said:

My long time service advisor has always told me not to use auto unless I'm off-road, even in the wet. Seems like it'd be OK on wet pavement, though. He says the front differential burns up easy.

His opinion but there is not basis in fact and shows his ignorance of that feature. I use AUTO and have for many years. If the roads are snow covered or wet, its in AUTO.   For instance this winter my truck has been in AUTO since November.  Even in wet pavement my rear tires will often break loose on the wet pavement.  I did not buy a truck with AUTO to save it for the next owner.  Acquaintance is a canine police officer and drives a 4wd Tahoe. Runs it in AUTO 24/7 and never had any issues.  Currently there's a 2024 Tahoe PPV sitting in the driveway but his last one was also a Tahoe.

 

From GM service info the SA never read. I only copied pertinent info.

Quote

AWD
The second category is an on-demand AWD. This type of AWD basically delivers torque only to a primary driving axle unless reduced traction is experienced. At that point, the system electronically or mechanically will apply torque to the other axle. Depending on the type of system, this can provide up to 100% of the torque to the axle with traction. These transfer cases use an electronically actuated clutch pack, a hydraulically actuated clutch pack, or a viscous coupling to allow for a difference in speed between the front and rear axles

AUTOMATIC TRANSFER CASES
The last category is a combination of 4WD and On Demand AWD. These transfer cases have a 2HI, Auto-4WD, 4HI, 4LO and Neutral position and would fall in the general 4WD category. This transfer case has the operating characteristics of both an On Demand AWD and a Part-Time 4WD system depending on the mode selected. This transfer case uses a clutch pack to allow for a difference in speed between the front and rear axles in the Auto-4WD mode. In the 4HI or 4LO modes, there is no allowance for the difference in speed between the front and rear axles.

 

Edited by Z45
  • Thanks 1
Posted

I run in 2WD most of the time.  In the winter, I may leave it on Auto during spells of bad weather.  I've put it in 4WD just to test it but have never actually needed it.

  • Thanks 1

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