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Off-Roading with the Single Speed Transfer Case: 4.3L and 2.7L

Justin Holland
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Justin Holland Enthusiast

Justin Holland

Posted
Posted

Hi All,

 

I currently have a 2020 GMC Sierra SLE 2WD 2.7L with the aFe power package (aka all products for the 2.7L).

 

I love my engine and truck, but regret not getting the 4WD variant. I only go off-pavement when hunting and light camping. 

 

I wanted to see how off-roading with only 4WD Hi and the G80 locker. 

 

Thanks for everyone's insight on this.

c.schill Enthusiast

c.schill

Posted
Posted

I have a 2019 Silverado LT 5.3. Different engine choice than what you're asking, but it does have the single speed transfer case and it does fine for me off road. The areas I frequent are not very intense, but like you, I am there for camping/hunting. I've been on rough dirt "roads", that are more just tracks through the woods, in wet summer weather and also snowy winter weather and haven't run into a situation where I thought I was in trouble. If you frequent areas with some very deep mud, or heavily rocky areas, I could see the need for a low range there, but I haven't felt like I miss having it in my case. I came from a 2016 K2 truck with z71 and the low range, and I can count on one hand the number of times I used that low range.

 

I'll attach some photos I have of the new truck in off road settings.

 

This is just my personal opinion on the single speed vs 2 speed t-case. Not saying that no one needs low range.

  • Like 1
redwngr Senior Enthusiast

redwngr

Posted
Posted

I'm a little confused.

 

Thread title suggests truck is 4wd, but with the transfer case that doesn't have 4LO.

Post indicates it's a 2wd.

 

 

My usage is farm/rural, and including running through snow - sometimes unplowed, sometimes drifted back in, so I do find situations where I use 4wd.

25 years running 4wd pickups and I don't think I've ever 'needed' 4LO.  Last few truck I haven't even bothered to test and see if 4LO would engage...

FWIW, I'm also not a fan of and don't use the 'autotrac' automatic 4wd mode that has been available on 1500's for a few years, and is available on HDs starting with the 2020's .

4wd HD's transfer cases are all 2 speed units - one with autotrac and one traditional. 

 

 

aseibel Senior Enthusiast

aseibel

Posted
Posted

If you have 4wd, you're good to go. Just keep decent tires on it. No real need for 4LOW. I've had it on last 2 trucks used for plowing snow and never engaged low range.

 

If you have 2wd, place ballast weight in the rear of the bed and stay out of the mud and snow off-road or you will get stuck. Summer time use, you should be fine. But make sure one of your friends has 4x4 or bring a winch in case you get stuck.

Justin Holland Enthusiast

Justin Holland

Posted
  • Author
Posted
1 hour ago, redwngr said:

I'm a little confused.

 

Thread title suggests truck is 4wd, but with the transfer case that doesn't have 4LO.

Post indicates it's a 2wd.

 

 

My usage is farm/rural, and including running through snow - sometimes unplowed, sometimes drifted back in, so I do find situations where I use 4wd.

25 years running 4wd pickups and I don't think I've ever 'needed' 4LO.  Last few truck I haven't even bothered to test and see if 4LO would engage...

FWIW, I'm also not a fan of and don't use the 'autotrac' automatic 4wd mode that has been available on 1500's for a few years, and is available on HDs starting with the 2020's .

4wd HD's transfer cases are all 2 speed units - one with autotrac and one traditional. 

 

 

Sorry for any confusion. I have a 2WD 2020 Sierra, but I am thinking of trading in for a 4WD variant with the 2.7L and G80. 

 

I wanted to see if anyone had any issues or got stuck because of no 4WD LO.

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted

Have you had a chance to price out the difference between trucks with single and two speed transfer cases?

 

If the price is minimal, I would go with the two speed, just in case you ever need it (plus if you have it, you will find a way to use it).

  • Like 1
c.schill Enthusiast

c.schill

Posted
Posted (edited)
2 hours ago, Justin Holland said:

Sorry for any confusion. I have a 2WD 2020 Sierra, but I am thinking of trading in for a 4WD variant with the 2.7L and G80. 

 

I wanted to see if anyone had any issues or got stuck because of no 4WD LO.

I've never gotten stuck anywhere, in either my 2019 or my 2016 in 4 hi with the G80. You do have to be willing to live with the wheel spin required to lock up the G80. Which I think is something like a 500rpm difference between the rear wheels. 

 

EDIT: apparently it's 120rpm. Google is cool. 

Edited by c.schill
  • Like 1
Justin Holland Enthusiast

Justin Holland

Posted
  • Author
Posted
19 minutes ago, JimCost2014 said:

Have you had a chance to price out the difference between trucks with single and two speed transfer cases?

 

If the price is minimal, I would go with the two speed, just in case you ever need it (plus if you have it, you will find a way to use it).

I am a 2.7L fan boy now, they only come in single speed. 

  • Like 1
JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted
3 minutes ago, Justin Holland said:

I am a 2.7L fan boy now, they only come in single speed. 

Makes your decision a lot easier.

 

Maybe drive another truck (different engine) with the two speed, engage it and see what you think. That way you would at least know what it does, and no regrets if you do not like it.

  • Like 1
Salsa De Piña Enthusiast

Salsa De Piña

Posted
Posted

After nearly twenty years and 3 GMs with two-speed transfer cases, I've used it once to pull a buddy up a steep, icy driveway.

 

Let's face it: you're probably not doing the Rubicon in your full-sized truck.  For everything else (from ATV trails, to tilled farmland, to getting out on the lake to the ice fishing shack) 4Hi will easily get the job done if you've got the right shoes on.

  • Like 2
  • Haha 1
Justin Holland Enthusiast

Justin Holland

Posted
  • Author
Posted

My thoughts

1 hour ago, Salsa De Piña said:

After nearly twenty years and 3 GMs with two-speed transfer cases, I've used it once to pull a buddy up a steep, icy driveway.

 

Let's face it: you're probably not doing the Rubicon in your full-sized truck.  For everything else (from ATV trails, to tilled farmland, to getting out on the lake to the ice fishing shack) 4Hi will easily get the job done if you've got the right shoes on.

My thoughts exactly!

redwngr Senior Enthusiast

redwngr

Posted
Posted
4 hours ago, Salsa De Piña said:

After nearly twenty years and 3 GMs with two-speed transfer cases, I've used it once to pull a buddy up a steep, icy driveway.

 

Let's face it: you're probably not doing the Rubicon in your full-sized truck.  For everything else (from ATV trails, to tilled farmland, to getting out on the lake to the ice fishing shack) 4Hi will easily get the job done if you've got the right shoes on.

Much better way of saying than my long winded reply...

  • Like 1
Z45 Senior Enthusiast

Z45

Posted
Posted

4 ↓(Four-Wheel Drive Low) : This setting engages the front axle and delivers extra
torque. Choose 4 ↓ when driving off-road in deep sand, deep mud, or deep snow, and
while climbing or descending steep hills. While driving in 4 ↓, keep vehicle speed
below 72 km/h (45 mph).

 

Note-Also useful when plowing snow as it puts less strain on the transmission

redwngr Senior Enthusiast

redwngr

Posted
Posted
5 hours ago, elcamino said:

4 ↓(Four-Wheel Drive Low) : This setting engages the front axle and delivers extra
torque. Choose 4 ↓ when driving off-road in deep sand, deep mud, or deep snow, and
while climbing or descending steep hills. While driving in 4 ↓, keep vehicle speed
below 72 km/h (45 mph).

 

Note-Also useful when plowing snow as it puts less strain on the transmission

and it disables traction control and stability control -- which can be useful in the deep stuff.

  • Like 1

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