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Couple of 4wd Questions

91 Shortbed Chevy

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91 Shortbed Chevy Enthusiast

91 Shortbed Chevy

Posted
Posted

Hi All. I have a 2019 Silverado 2500HD with the 6.0 gas and the transfer case selector on the dash. I live in Indiana and lately we haven't had really bad winters. I have a couple of questions regarding using my 4wd. First, at what speed can i safely engage 4wd from 2wd? I have heard that you don't have to slow down to do this in the newer trucks but i don't want to take a chance of damaging something. Second, what should be my maximum speed in 4hi? Obviously if i need 4wd i shouldn't be flying but i am curious what is safe for my drivetrain. Thanks for your input.

91 Shortbed Chevy Enthusiast

91 Shortbed Chevy

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  • Author
Posted
9 hours ago, davester said:

the answers to your questions will be in the owners manual.

I knew there would be info in the manual, just wondered if any members could give me some real world info. I know what is in the manual isn't always what has worked best for people. A friend that built these trucks for 30 years told me not to use the auto 4wd selection on my 2003 Silverado because GM had a lot of warranty claims because of them. Just wondered what others are doing.

rbrjr1 Enthusiast

rbrjr1

Posted
Posted

I dont leave mine in auto.

it's either 2H (normally), 4H snow and what not, 4L stuck

steelcity Enthusiast

steelcity

Posted
Posted

My son left his in "auto" and a "service 4wd" message kept coming up.  Dealership said not to ride around like that every day on pavement, only when on dirt roads or such.

oak 1971 Enthusiast

oak 1971

Posted
Posted
16 hours ago, 91 Shortbed Chevy said:

Hi All. I have a 2019 Silverado 2500HD with the 6.0 gas and the transfer case selector on the dash. I live in Indiana and lately we haven't had really bad winters. I have a couple of questions regarding using my 4wd. First, at what speed can i safely engage 4wd from 2wd? I have heard that you don't have to slow down to do this in the newer trucks but i don't want to take a chance of damaging something. Second, what should be my maximum speed in 4hi? Obviously if i need 4wd i shouldn't be flying but i am curious what is safe for my drivetrain. Thanks for your input.

That is about to change if it hasn't already.

oak 1971 Enthusiast

oak 1971

Posted
Posted
5 hours ago, steelcity said:

My son left his in "auto" and a "service 4wd" message kept coming up.  Dealership said not to ride around like that every day on pavement, only when on dirt roads or such.

Interesting, I got the same message driving in snow/slush today.

redwngr Senior Enthusiast

redwngr

Posted
Posted
21 hours ago, rbrjr1 said:

I dont leave mine in auto.

it's either 2H (normally), 4H snow and what not, 4L stuck

 

20 hours ago, steelcity said:

My son left his in "auto" and a "service 4wd" message kept coming up.  Dealership said not to ride around like that every day on pavement, only when on dirt roads or such.

2015-2019 HD doesn't have 'auto mode' 4wd 

(yes, it's available on the 2020 models)

 

redwngr Senior Enthusiast

redwngr

Posted
Posted
On 10/31/2019 at 5:02 AM, 91 Shortbed Chevy said:

Hi All. I have a 2019 Silverado 2500HD with the 6.0 gas and the transfer case selector on the dash. I live in Indiana and lately we haven't had really bad winters. I have a couple of questions regarding using my 4wd. First, at what speed can i safely engage 4wd from 2wd? I have heard that you don't have to slow down to do this in the newer trucks but i don't want to take a chance of damaging something. Second, what should be my maximum speed in 4hi? Obviously if i need 4wd i shouldn't be flying but i am curious what is safe for my drivetrain. Thanks for your input.

I frequently change between 2H and 4H during fall/winter.  

 

My normal practice is to be foot-off-throttle when switching to 4H, so all wheels are running the same speed during the 4H engage.  

What I avoid is engaging 4wd when the rears are spinning.

Never had any 4wd issues.  

 

IMO, if it's safe to be running at speed xyz, then it's safe to do the switch at speed xyz. 

 

Try to avoid forgetting to disengage the 4wd when you get to a surface with good traction. 

 

 

 

 

rbrjr1 Enthusiast

rbrjr1

Posted
Posted
24 minutes ago, redwngr said:

Try to avoid forgetting to disengage the 4wd when you get to a surface with good traction. 

 

key right here..!

 

when I had a S15 GMC Jimmy back in the 90's, I made a 300 mile road trip in 4H.. at 70mph..

 

(young and dumb)

91 Shortbed Chevy Enthusiast

91 Shortbed Chevy

Posted
  • Author
Posted
On 10/31/2019 at 9:47 PM, oak 1971 said:

That is about to change if it hasn't already.

Do you have some insight on the winter forecast for Indiana?

steelcity Enthusiast

steelcity

Posted
Posted
On 11/1/2019 at 1:09 PM, redwngr said:

 

2015-2019 HD doesn't have 'auto mode' 4wd 

(yes, it's available on the 2020 models)

 

You're right, his is a 1500

redwngr Senior Enthusiast

redwngr

Posted
Posted
39 minutes ago, steelcity said:

You're right, his is a 1500

OP says he has a "2019 Silverado 2500HD with the 6.0 gas and the transfer case selector on the dash".

 

Info about what happens with a 1500 doesn't answer is question at all... and just might add to his uncertainty. 

 

 

 

 

steelcity Enthusiast

steelcity

Posted
Posted
On 10/31/2019 at 2:48 PM, 91 Shortbed Chevy said:

 A friend that built these trucks for 30 years told me not to use the auto 4wd selection on my 2003 Silverado because GM had a lot of warranty claims because of them. Just wondered what others are doing.

 

5 hours ago, redwngr said:

OP says he has a "2019 Silverado 2500HD with the 6.0 gas and the transfer case selector on the dash".

 

Info about what happens with a 1500 doesn't answer is question at all... and just might add to his uncertainty. 

 

 

 

 

Calm down Francis, just replying to  the OP's second post.  He said he was wondering what others are doing about the auto 4wd select and I am answering.

  • 3 weeks later...
CO-Stark Enthusiast

CO-Stark

Posted
Posted
On 10/31/2019 at 3:02 AM, 91 Shortbed Chevy said:

Hi All. I have a 2019 Silverado 2500HD with the 6.0 gas and the transfer case selector on the dash. I live in Indiana and lately we haven't had really bad winters. I have a couple of questions regarding using my 4wd. First, at what speed can i safely engage 4wd from 2wd? I have heard that you don't have to slow down to do this in the newer trucks but i don't want to take a chance of damaging something. Second, what should be my maximum speed in 4hi? Obviously if i need 4wd i shouldn't be flying but i am curious what is safe for my drivetrain. Thanks for your input.

This was definitely on a previous truck, I'm guessing it was my 2006 Titan, but I believe it was in the owner's manual that they recommended keeping 2WD to 4WD shifts under 60mph. Personally I've maintained that as a rule of thumb, but truth is these trucks have so many sensors and safeties built in, it won't complete the shift if doing so at your current speed would cause any issues.
Because it just happened to me I'll mention this scenario, even if you shift to 4hi at a stop, let it complete the shift before you get on her...I was at a light and put it in 4 so I could get off the line, but the light changed sooner than I expected. Rear spins, I let off, and *clunk* when it was able to get into 4WD. Doubt there's lasting damage from that one time but not something you want to make a habit of, to say the least.

 

Maximum speed in 4hi?!? Mash the throttle and find out LOL. I'm not positive but pretty sure I've had mine up to 85-90mph with no issues.

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