transfer case

[6.5coalroller]

Recently blew a head gasket on my six five so we pulled the motor out cuz it's a pain in the rear to do in the truck. Rite now i'm running an hx-35 and I would like to either drop the compression to run it safer. Or buy the a-team turbo. Either route i'll prolly have over a thousand in it when it's all said and done just in replacing a few engine parts/maintenance items. So I wanted to look at all my options. Been looking into doin the cummins conversion also. If I went ahead and did it i would wanna go to the nv4500 instead of the 4l80e but I was wondering if I could still use the transfer case I have now.

 

[88gmctruck]

It's possible.

The big problem is the dodge and chevy use both a different bellhousing and tailhousing, and thus different boltpatterns.

IIRC you'd have to swap the mainshaft and tailhousing out of a GM NV4500 into the dodge unit. Considering the dodge trucks use a driver's side differential, you could easily run the dodge NP241 without too much problem.

 

[6.5coalroller]

Thats kinda what I figured i've heard of the np241 being used. Found one on craigslist for 250. Still debating what to do tho so many possibilitys.

 

[88gmctruck]

Yes but it has to be the dodge NP241HD if you planning on putting it behind the cummins/NV4500. The GM and Dodge NP241 use a different bolt pattern so they aren't interchangeable. The Dodge NP241 is also fixed rear yolk (which is a plus) but will require a new driveshaft. Best bet is going to be find a complete truck and get all you need. I just put a GM NV4500 in my truck, and you'll need a few items from a GM manual such as the pedal, weld in pedal bracket, clutch safety switches, hydraulic lines, etc.

Also consider how the cummins is going to fit in your frame and what it's going to do with the IFS. I have no idea on the fitment of that along with the suspension/driveline/etc up front.

 

[THEFERMANATOR]

You can use a GM NV4500 with a DODGE input shaft and bolt it up to the CUMMINS, but the GM NV4500 isn't as heavy duty as the DODGE NV4500 for the CUMMINS. The other option is to use a DODGE NV4500 and transfer case, then swap over the output shaft and tailhousings from the GM one to retain the factory speed sensor, but then you get the smaller GM transfer case tailshaft. I believe there are a few companies out there that offer a tone wheel for the DODGE case and then you could run the GM tailhousings to retain your speed sensor for the speedo. The DODGE and GM transfer cases both use the same bolt pattern, but they are clocked 90 degrees different from each other so that you can't swap them out amongst each other. I don't know if you can use an ADVANCED ADAPTERS clocking ring to correct it either.

 

[6.5coalroller]

ya to really do it rite I would need a solid axle swap so I could easily see big $$$.

 

[88gmctruck]

You can use a GM NV4500 with a DODGE input shaft and bolt it up to the CUMMINS, but the GM NV4500 isn't as heavy duty as the DODGE NV4500 for the CUMMINS. The other option is to use a DODGE NV4500 and transfer case, then swap over the output shaft and tailhousings from the GM one to retain the factory speed sensor, but then you get the smaller GM transfer case tailshaft. I believe there are a few companies out there that offer a tone wheel for the DODGE case and then you could run the GM tailhousings to retain your speed sensor for the speedo. The DODGE and GM transfer cases both use the same bolt pattern, but they are clocked 90 degrees different from each other so that you can't swap them out amongst each other. I don't know if you can use an ADVANCED ADAPTERS clocking ring to correct it either.

You can only used a GM NV4500 with a dodge input shaft if it's a 2nd gen GM NV4500 (95+) as the 92-94 version uses a lower gearing that dodge never had.

If they are the same bolt pattern, you should be able to use the clocking ring, however, the transfer cases also have different input shaft splines which further complicate things.

 

[THEFERMANATOR]

You can only used a GM NV4500 with a dodge input shaft if it's a 2nd gen GM NV4500 (95+) as the 92-94 version uses a lower gearing that dodge never had.

If they are the same bolt pattern, you should be able to use the clocking ring, however, the transfer cases also have different input shaft splines which further complicate things.

I thought it was 94+ had the same 1st gear like that of the DODGE as 94 was when DODGE started using them. In the GM's they were all 32 spline outputshafts, but DODGE had 23 on some of the early ones and in 98 when the NV4500HD was introduced for the 24V engines they went to a 29 spline but some still had the 23 spline on up to 00 IIRC. All of the NP241's in the DODGES I ever worked on all had a slip yoke on them, so I don't know when they went to a fixed yoke.

 

[88gmctruck]

The GM Parts Cataloluge has a parts break between 94 and 95 for the NV4500 as well. 92-94 GM NV4500 used the RPO code MT8, while the 95+ used MW3. The NV4500 I picked up is from a 94 and is RPO MT8, and has the 6.34:1 ratio.

RPO MT8 - TRANSMISSION,MANUAL,5-SPD,NEW PROCESS 5-SPD M/TRANS(MT8)
RPO MW3 - TRANSMISSION,MANUAL,5 SPEED,NEW VENTURE GEAR,109MM,5.61 1ST,O/D 5-SPD M/TRANS(MW3)

Additional Background from Quad4x4.com

For Dodge:
The light duty 1" 19 spline input shaft used in 1992-93 was changed to 1 1/8" 10 spline in 1994.

1992-93 models had a coarse thread shift stub. This was replaced by a square stub that accepted a press on shift lever for 1994-1997. A metric threaded shift stub was introduced for 1998.

1992-1996 had an interlock mechanism built into the 1-2 syncro to prevent high speed downshifts into 1st or second gear. This feature was dropped during the 1996 model year

In 1997, New Venture changed the design of reverse gear from a dual plane to a single plane. The reverse gear ratio was changed from 5.61:1 to 5.04:1.

For 1998, the shift tower and shift handle were redesigned. 2WD models no longer had a speedometer drive (the speedo works off the rear axle). 4x4 tailshaft housings were changed to eliminate mountings for the transfer case shift lever. Also, with HD models, the mainshaft nut was redesigned late in 1998. This change first showed up on transmissions with an AD suffix on the Dodge part number (ex: 52108131AD)


For GM:

1992-1994 transmissions had a wider gear ratio with 1st gear being 6.34-1. Starting in 1995, the 1st gear ratio was changed to 5.61-1.

1992-1998 models did not have a synchronized reverse gear. A synchronized reverse was introduced for the 1999 model year

1992-93 models had an interlock mechanism built into the 1-2 syncro to prevent high speed downshifts into 1st or second gear. This feature was dropped for 1994 according to our GM parts book, however we have found them on some 1994 transmissions.

1992-1995 transmissions had a bellhousing bolt pattern unique to GM. For 1996 and newer transmissions, GM uses the Dodge bolt pattern.

In 1997, New Venture changed the design of reverse gear from a dual plane to a single plane. The reverse gear ratio was changed from 5.61:1 to 5.04:1

 

[Extremesounds13]

I have my 94 GM 241 case and a 95 Dodge 241 case both apart right now trying to make everything work, and they are two very different units, can anyone steer me in the right direction here?

 

[THEFERMANATOR]

Are you sure that your DODGE trtansfer case is a regular 241 and not the HD version? DODGE used both versions behind the CUMMIN S engine from 94+.

 

[Extremesounds13]

it is a 241DLD so its not the HD version.