Can you install a 2 speed transfer case in to a vehicle with a single speed?

[swathdiver]

2010 is when GM changed transfer cases in all their 1500 drivetrains since the old case was having too many problems.

First I've heard of this. Are you saying GM switched to something other than the Magna Power MP3023/3024 2-speed transfer cases?

 

[NotBabb]

First I've heard of this. Are you saying GM switched to something other than the Magna Power MP3023/3024 2-speed transfer cases?

That's the information I've found. My neighbor has a 2007 avalanche with the 2 speed transfer case and it's nothing like the newer one in my truck.

 

[swathdiver]

So did you have an MP3010 originally? What do you have now?

 

[Tozan]

Hey, just remembered this thread when I was looking up information on doing this swap with my tahoe.

2010 is when GM changed transfer cases in all their 1500 drivetrains since the old case was having too many problems. This was also the year they changed the base model 4x4 to have the single speed transfer case and having the 2 speed as an optional extra.

Going into figuring this swap out for my tahoe was a bit challenging since there really wasn't a lot of info on the transfer cases. Knowing how car manufacturers operate was a big help. After finding out the 2 speed was an optional extra, I knew the wiring harness would all be the same so the factory could just install 1 wiring harness on the chassis and not have to change it again. Also the motor on the transfer case is changed by what voltage is sent to it and not having an extra wire, so that threw needing the wiring harness out. The selector switch is obviously different so I knew I would need that. The hard part was finding out if the TCU needed to be changed. After I looked up all I could about it I was under the impression they were all the same, but when I went to install the new case I found out they are different.

As to what you need for the swap, you will need the 2 speed case, oem 2 speed selector switch, and 2 speed TCU.

All the TCUs and cases should have the exact same electrical plugs. The only difference you will find is on the selector switch. Certain ones will have a little different shape with cut outs on the top of the plug so you will just have to make sure that the switch will fit your model suv.

All my parts came out of a 2012 z71 silverado and they all worked on my 2010 tahoe so any 1500 drivetrain out of any year model between 2010-2014 should work.

I was lucky to find a guy near where I live that parts 07 and newer GM trucks and suvs for a living so I was able to drive to him and do some testing to make sure everything worked.

All the parts together cost me $290. Obviously that's not installed, I did that myself. It only took me 2 hours since I had taken my transfer case out once before and I didn't need to jack my truck up since its already lifted 8".

If you have any more questions let me know.

Wow thanks a lot that is great news, I was hoping it would not be a real big deal. Now to start looking for parts.

 

[NotBabb]

So did you have an MP3010 originally? What do you have now?

Yes I had the MP3010 originally and I replaced it with a MP3023.

I think I got confused when you asked if gm used something other than the mp2023/2024.

From what I've seen, 2010 is when they changed to using magnapower transfer cases which is also when they changed to the 6l80.

I thought they were still using the NV cases in 2007-2009.

 

[swathdiver]

From what I've seen, 2010 is when they changed to using magnapower transfer cases which is also when they changed to the 6l80.

Go back one more year to 2009. See my signature? GMT900 Yukon Denalis always used the 6L80 and the 2500s switched over to the 6L90/MP3024 in 2008.

Only thing I cannot presently remember is which t-case I have, the MP3023 or MP3024. Probably the former, will have to check next oil change.

 

[NotBabb]

Go back one more year to 2009. See my signature? GMT900 Yukon Denalis always used the 6L80 and the 2500s switched over to the 6L90/MP3024 in 2008.

Only thing I cannot presently remember is which t-case I have, the MP3023 or MP3024. Probably the former, will have to check next oil change.

Ah ok, I'm far from an expert at what parts came in what. I am an expert at breaking rearends and transmissions though. Lol

First rearend was installed wrong and cooked the bearings. Second rearend lasted a year until the G80 grenaded and also took out second gear in the transmission. Third rearend went through 2 sets of spider gears in 2 months until Yukon ponied up the cash to just have a Detroit tru-trac locker installed and I haven't had any problems since.

 

[Tozan]

Today I installed the following for the upgrade. All used parts were from the same vehicle a 2011 Tahoe 50K miles with the optional 2-speed transfer case.

Parts:
Two speed transfer case
Electric Transfer shifter
Transmission control unit
Control switch in dash
2 quarts of Auto trak II oil

The job took a casual 3 hours to install and test. Since I have a lifted Tahoe we didn't need to jack it up.

Removed:
Both drive shafts
Cross member, wiring and the vent line.

Then dropped the transfer case cleaned off the old gaskets and replaced the rear out put seal since it was off another vehicle. Then installed the used transfer case and put the rest of it back together.

Pried out the plastic piece holding the shift control knob pushed on the retaining tabs and installed the new control button. Then popped it back in Be sure to keep the plastic piece square when you reinstall it so it will pop right in.

Remove the kick panel under the steering wheel by removing 2 screws and one bolt.With the panel removed you will be able to look about 6 inches back and see the Transmission control unit. There are three plugs remove all of them and hit the tabs on the top and bottom to release the TCU then reinstall the unit.

That's it no reprogramming, changing wiring harnesses or anything like that it is a simple plug and play upgrade...

 

[Tozan]

Went out and road tested it and everything is working fine...

Total cost on this was around $450.00
And Three hours.

 

[swathdiver]

2 quarts of Auto trak II oil

Swap that out for Dexron VI Charles. The MagnaPower transfer cases use transmission fluid.

Glad this swap is plug and play without any programming required.