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Pto Status Is On. Does This Mean Transfer Case Is Engaged In 4wd?

BigSilver

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BigSilver Enthusiast

BigSilver

Posted
Posted

2003 Suburban, 2500, 6L, 4WD

 

According to the dashboard display, the truck is running in 2WD, and all the related dashboard buttons function,

no 4WD dashboard failure alerts.

 

Recently hooked up an OBD2 scanner and found that the PTO heading was ON.

Is this an indication that the transfer case is engaged in 4WD,

even though dashboard displays 2WD?

alwcurlz Enthusiast

alwcurlz

Posted
Posted
2003 Suburban, 2500, 6L, 4WD

 

According to the dashboard display, the truck is running in 2WD, and all the related dashboard buttons function,

no 4WD dashboard failure alerts.

 

Recently hooked up an OBD2 scanner and found that the PTO heading was ON.

Is this an indication that the transfer case is engaged in 4WD,

even though dashboard displays 2WD?

 

So you have the Allison transmission with PTO. That is a separate component built into your transmission for powering external things like a hydraulic or water pump off the side. But, I'm not familiar with how to control it however, there must be a control in the cab for turning it off/on?

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

Doubt it has an Allison trans as its a 6.0L

As far as I know only the 3500 with the 6.0L came with the Allison trans...and the usual suspects of course the D-Max and the 8.1L gasser.

 

But there were some vehicles in the 2500 line that came with the Allison...so he could have one in there.

 

 

The PTO is exactly what adber said though...

BigSilver Enthusiast

BigSilver

Posted
  • Author
Posted
2003 Suburban, 2500, 6L, 4WD

 

According to the dashboard display, the truck is running in 2WD, and all the related dashboard buttons function,

no 4WD dashboard failure alerts.

 

Recently hooked up an OBD2 scanner and found that the PTO heading was ON.

Is this an indication that the transfer case is engaged in 4WD,

even though dashboard displays 2WD?

 

So you have the Allison transmission with PTO. That is a separate component built into your transmission for powering external things like a hydraulic or water pump off the side. But, I'm not familiar with how to control it however, there must be a control in the cab for turning it off/on?

 

 

 

Doubt it has an Allison trans as its a 6.0L

As far as I know only the 3500 with the 6.0L came with the Allison trans...and the usual suspects of course the D-Max and the 8.1L gasser.

 

But there were some vehicles in the 2500 line that came with the Allison...so he could have one in there.

 

 

The PTO is exactly what adber said though...

 

You may be correct, as I bought this burb 2nd hand. It was formerly used by the electric utility.

Now I am curious on how to make use of this hidden treasure.

Thanks for the input.

alwcurlz Enthusiast

alwcurlz

Posted
Posted
2003 Suburban, 2500, 6L, 4WD

 

According to the dashboard display, the truck is running in 2WD, and all the related dashboard buttons function,

no 4WD dashboard failure alerts.

 

Recently hooked up an OBD2 scanner and found that the PTO heading was ON.

Is this an indication that the transfer case is engaged in 4WD,

even though dashboard displays 2WD?

 

So you have the Allison transmission with PTO. That is a separate component built into your transmission for powering external things like a hydraulic or water pump off the side. But, I'm not familiar with how to control it however, there must be a control in the cab for turning it off/on?

 

 

 

Doubt it has an Allison trans as its a 6.0L

As far as I know only the 3500 with the 6.0L came with the Allison trans...and the usual suspects of course the D-Max and the 8.1L gasser.

 

But there were some vehicles in the 2500 line that came with the Allison...so he could have one in there.

 

 

The PTO is exactly what adber said though...

 

You may be correct, as I bought this burb 2nd hand. It was formerly used by the electric utility.

Now I am curious on how to make use of this hidden treasure.

Thanks for the input.

 

 

A PTO driven hydraulic pump would be real nice if you decided to install a hydraulic Milemarker winch on the truck like the US Military puts on their Humvees. Hydraulic winches are much stronger and efficient but expensive.

BigSilver Enthusiast

BigSilver

Posted
  • Author
Posted
2003 Suburban, 2500, 6L, 4WD

 

According to the dashboard display, the truck is running in 2WD, and all the related dashboard buttons function,

no 4WD dashboard failure alerts.

 

Recently hooked up an OBD2 scanner and found that the PTO heading was ON.

Is this an indication that the transfer case is engaged in 4WD,

even though dashboard displays 2WD?

 

So you have the Allison transmission with PTO. That is a separate component built into your transmission for powering external things like a hydraulic or water pump off the side. But, I'm not familiar with how to control it however, there must be a control in the cab for turning it off/on?

 

 

 

Doubt it has an Allison trans as its a 6.0L

As far as I know only the 3500 with the 6.0L came with the Allison trans...and the usual suspects of course the D-Max and the 8.1L gasser.

 

But there were some vehicles in the 2500 line that came with the Allison...so he could have one in there.

 

 

The PTO is exactly what adber said though...

 

You may be correct, as I bought this burb 2nd hand. It was formerly used by the electric utility.

Now I am curious on how to make use of this hidden treasure.

Thanks for the input.

 

 

A PTO driven hydraulic pump would be real nice if you decided to install a hydraulic Milemarker winch on the truck like the US Military puts on their Humvees. Hydraulic winches are much stronger and efficient but expensive.

 

Yes, that would be a top notch setup.

Anyone have info (photo or shop manual drawing) on where to find the PTO controller and its respective output port?

alwcurlz Enthusiast

alwcurlz

Posted
Posted
2003 Suburban, 2500, 6L, 4WD

 

According to the dashboard display, the truck is running in 2WD, and all the related dashboard buttons function,

no 4WD dashboard failure alerts.

 

Recently hooked up an OBD2 scanner and found that the PTO heading was ON.

Is this an indication that the transfer case is engaged in 4WD,

even though dashboard displays 2WD?

 

So you have the Allison transmission with PTO. That is a separate component built into your transmission for powering external things like a hydraulic or water pump off the side. But, I'm not familiar with how to control it however, there must be a control in the cab for turning it off/on?

 

 

 

Doubt it has an Allison trans as its a 6.0L

As far as I know only the 3500 with the 6.0L came with the Allison trans...and the usual suspects of course the D-Max and the 8.1L gasser.

 

But there were some vehicles in the 2500 line that came with the Allison...so he could have one in there.

 

 

The PTO is exactly what adber said though...

 

You may be correct, as I bought this burb 2nd hand. It was formerly used by the electric utility.

Now I am curious on how to make use of this hidden treasure.

Thanks for the input.

 

 

A PTO driven hydraulic pump would be real nice if you decided to install a hydraulic Milemarker winch on the truck like the US Military puts on their Humvees. Hydraulic winches are much stronger and efficient but expensive.

 

Yes, that would be a top notch setup.

Anyone have info (photo or shop manual drawing) on where to find the PTO controller and its respective output port?

 

 

What you'll need to do is look at the RPO codesheet in the glovebox that lists the options included with your truck and find your transmission code. It begins with an M. Something like MNK, MNZ, MP8, MP9, MTP, MTU. That'll give you some info you can use to search for more info on the net. I would just crawl underneath and look for a shaft that would extend outside the transmission.

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