# Gmc 3500 transfer case



## Bulldozer (Jan 20, 2008)

I believe that the transfer case in my 2001 GMC 3500 bound uppayup in the middle of the driveway will know more in morning. 

I was wondering what your thoughts are in regards to a rebuild, replacement or is there an upgrade from OEM.

Thank you for your time in advance.

Philip


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## VPRacing (Dec 26, 2009)

Auto, Manual transmission?

If auto, 4 or 5spd

If Manual, 5 or 6spd

Floor shift transfer case or electronic on the dash?


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## Bulldozer (Jan 20, 2008)

5 speed auto transmission with tow haul and floor shift transfer case.

Thanks 
Philip


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## B&B (Nov 4, 2006)

Bound up? Could you provide more detail?


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## JustinD (Jan 14, 2008)

Allison trans?


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## Bulldozer (Jan 20, 2008)

B&B;941933 said:


> Bound up? Could you provide more detail?


What happened was I was backing up and I heard a small noise drove forward about 20 feet and went to back up and it wouldn't. The transmission seem to be engaging and I can move the transfer case between 2H and 4H but can't get into N and 4L so I had to drag the truck back about 20 feet so that I can get out of in front of the garage and get headed out the driveway. I could still drive forward so I drove in 2H real slow about 2 tens of a mile to the office and made it about 3/4 of the way up my driveway and it lost all movement. The motor is still engaging with the transmission


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## VPRacing (Dec 26, 2009)

If it comes down to replacing it:

I can find 2 in NH...

One for $875 and the other for $950...

$950 - Turnpike Auto Parts USA-NH(New-Ipswich) 1-603-878-1500 
$875 - P and L Auto Parts, Inc. USA-NH(Berlin) 1-800-237-1040

Not sure what it would cost for a rebuild... Check around, might be less than a junkyard T-case.


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## B&B (Nov 4, 2006)

Bulldozer;941993 said:


> What happened was I was backing up and I heard a small noise drove forward about 20 feet and went to back up and it wouldn't. The transmission seem to be engaging and I can move the transfer case between 2H and 4H but can't get into N and 4L so I had to drag the truck back about 20 feet so that I can get out of in front of the garage and get headed out the driveway. I could still drive forward so I drove in 2H real slow about 2 tens of a mile to the office and made it about 3/4 of the way up my driveway and it lost all movement. The motor is still engaging with the transmission


So it simply feels as though the E-brake is on? Definitely could be a T-case issue then. They don't normally die catastrophically like that without warning but as with anything mechanical anything is possible.

Ever check the fluid level in it? A low fluid level is what kills them quick.


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## lilweeds (Aug 3, 2007)

Well actually it's the pumb rub that will kill them quick


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## aeronutt (Sep 24, 2008)

The newer t-cases aren't known for being particularly weak, but they can and do fail occasionally. The only way to know the extent of damage is to tear it apart. I've pulled a NP-231 t-case from a U-Pull-It for $75 so if you can find that kind of deal it's not even worth the trouble of opening up the old one! Yours isn't a 231 though so it will probably cost more. You can get the model number from a small metal disk on the back of the case...


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## B&B (Nov 4, 2006)

aeronutt;943163 said:


> You can get the model number from a small metal disk on the back of the case...


It would be a 261.

Pump rub will kill them but you'll find a fluid leak first. Which of course would be noticeable if your under there checking the fluid level, and is the reason I asked.


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## Bulldozer (Jan 20, 2008)

My mechanic came and hauled if off. It is the transfer case Burnt oil and metal in it. Found out from the dealer that it has a MT1 4L80E transmission and NP2?? Transfer case. Will find out in the morning what rest of the numbers is when I go to see what i'm going to do. Would you go with OEM or is there an upgrade that would be better.


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## Bulldozer (Jan 20, 2008)

B&B;942958 said:


> So it simply feels as though the E-brake is on? Definitely could be a T-case issue then. They don't normally die catastrophically like that without warning but as with anything mechanical anything is possible.
> 
> Ever check the fluid level in it? A low fluid level is what kills them quick.


My mechanic checked it about a month ago when the transmission was serviced for the season and it was fine


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## lilweeds (Aug 3, 2007)

I know I'm anal about maintenance, but I rarely ever check the diffs or transfer case, till they need to be changed. If you case is junk, it would be worthwhile to put one of the 3 pump rub fix kits in there while your at it. I choose the one from Sonnax. Worked well.


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## aeronutt (Sep 24, 2008)

The 261 t-case is very durable. Just because you've experienced a failure with one doesn't mean you should swap it out for something else. Stick with the 261, get the pump-rub fix that was already mentioned, and put it back in. You'd be one AMAZINGLY unlucky dude to blow up a second one! The pump-rub problem is the Achilles Heel of the 261 and it's way easier to fix before it breaks. Since you've got it out already, it would be silly not to do this upgrade...


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## B&B (Nov 4, 2006)

Bulldozer;943429 said:


> My mechanic came and hauled if off. It is the transfer case Burnt oil and metal in it. Found out from the dealer that it has a MT1 4L80E transmission and NP2 transfer case.


 You said it was a 5 speed? If its a 4L80E it isn't a five speed. But regardless, if it's a 6.0 truck with a manual shift T-case then its the 4L80E and NVG261 T-case.



Bulldozer;943429 said:


> Would you go with OEM or is there an upgrade that would be better?


Reman would really be the best choice overall. You could easily spend $800 in parts alone on rebuilding yours if it's really burned up bad. Junk yard units are a gamble as you have no indicator if it was ever run low on fluid. Which they're famous for and is what kills them off early.


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## Bulldozer (Jan 20, 2008)

B&B;943521 said:


> You said it was a 5 speed? Oops was counting reverse.If its a 4L80E it isn't a five speed. But regardless, if it's a 6.0 truck it is with a manual shift T-case then its the 4L80E and NVG261 T-case.
> 
> Reman would really be the best choice overall. You could easily spend $800 in parts alone on rebuilding yours if it's really burned up bad. Junk yard units are a gamble as you have no indicator if it was ever run low on fluid. Which they're famous for and is what kills them off early.


Reman is probably what is going to be done. It is quicker to get truck on the road.

The question is do they put the pump rub kit in them.

Headed to look at it.
Philip


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## lilweeds (Aug 3, 2007)

A reman unit will most likely never have a pump rub kit in it. If you go to merchant auto's website they have great instruction that will help you with whatever kit you choose to install. Like I said I went with the sonnax kit which I think was a great kit for the money, but the Merchant Kit is very nice (although pricey) and Kennedy Diesel's kit will work as well. Do you research over at diesel place, lot's of info there on pump rub.


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