tanz45

iTrader: (1)

Good swap to do if you are doing a SAS like myself or just want the ability to put on a SYE to rid yourself of the weak and clunky slip yoke front and rear driveshafts.


If/when doing a Solid Axle Swap (SAS) in a NBS silverado, the NP246 autotrac transfer case will not work for several reasons:

1. The elimination of the ABS and front speed sensors will cause the auto 4wd to burn up and ruin case.

2. A fixed yoke is needed for the front drive shaft rather than the 246's slip yoke.

So what do you need??? A NP241 from a OBS, mid 90's to 98. If you have a automatic, make sure you get a transfer case from an automatic. If not you will not have the proper splines on the input shaft. The NP241 VSS will work with your current computer and will wire up in 2 seconds.

Another advantage of the NP241 is that a Slip Yoke Eliminator (SYE) is available for a rear drive shaft with a severe angle. This will eliminate that well known ''clunk'' and add strength to the tailshaft.



Looking at the two cases, you will see that the 246 uses studs to attach to adapter and the 241 uses bolts. Just use bolts and the original 246 adapter which is on your truck, DO NOT use the NP241 adapter. It just won't fit.

Once the 246 is out and the 241 is in its place you are going to have alot of extra wires. The only wires that matter are the two wires for the original VSS. The two wires are green and purple. You can either buy the pigtail for the 241 VSS or simply solder two wires to VSS and silicone them as I did. Saves you the cost of the pigtail (roughly $48 from GM).



Install the rear driveshaft, which will match right up, and verify that you are getting a reading to your speedo. I taped up all my extra pigtails and wiring because you just never know.

As for making brackets to hook up the manual 4x4 shifter....I am lazy and haven't done it yet.

And if you go SYE for the rear:

The parts


Installed with new driveshaft.

ChevyTruck

iTrader: (39)

southern_chevy

iTrader: (9)

Some good info there. Anyone know what the least amount of lift you can get away with doing a SAS? What plans do you have for your truck?

tanz45

iTrader: (1)

10 inches using leaf springs. That is 6'' from a kit (Sky-Manufacturing) and 4 inches from stock 52'' rear leafs off a 73-87 1/2 ton. Better off getting the heavy dutys as well. If you do less you will run into steering binding up on you since a cross over system is needed.

I already removed the leaf spring set up and switched to a coilover 3 link. Round 11-13 inches off lift. Haven't gotten the coils mounted yet.

Chevy Cowboy

iTrader: (5)

For anyone looking into doing this swap and not going sas, you will need a new front driveshaft, also you will need to rewire the front axle actuator, as the actuator is controlled by the tccm in trucks that are equipped with a np246 or np243 ( i think thats the number, which ever one is the electric shift without autotrac)

Crank1

Bringing up an old post, This is good tech on the 246-241 Swap. I've been considering this for some time now. Any more pics of the shifter or anything else? Thanks

tanz45

iTrader: (1)

I am lazy and i just got my new tranny in the truck. Shifter was put off for a loooong time, but i plan on getting to it soon.

It is 1 linkage rod. I have been periodically looking for a GM floor shifter but have also found many jeep and dodge truck 4wd shifters on Ebay. Too many projects these days, i get nothing done.

I can take a few more pics and post em up.

Matt75

Anyone know who manufactured this SYE kit?
I bought a used t-case with this one installed and need to find parts.

Thanks,
mf

tanz45

iTrader: (1)

JB Conversions is the Manufacturer.

zuren

I joined this site specifically for this thread; I have a very strong interest in this project. I'm looking to replace a BW4473 in a Chevy Express van with a manual shift NP241. It appears to be very similar to the swap here with the exception of a cross-member that may need to be notched for the front drive shaft.

I would like to hear the ideas for shifting. I'm looking at a Jeep shifter (cheap, can find then anywhere) and a kit from Novak that uses a cable and brackets. I figure a cable will make the install a little easier.

Thanks!