Transfer case-axles questions.

[Phuloi68]

Need some opinions (and pictures) on putting together a chevy 4x4. I have axles from a 79 1/2t, a 85 1/2t and a 81 1/2t. I have a 203 transfer case and a 205 transfer case. I will be using a 81 longbed frame.

I am trying to figure the best combination to use. I will be doing some snowplowing, trailer hauling, and highway driving. I think the ratios on the 79 and 85 axles are 3.73's and the 81 is 3.08's. I am leaning on using the 308's with the 205 t/c coupled to a 350 trans and 350 eng. Any opinions on which to use?

The 205 transfer case is mounted in the 81 frame but I don't think it's original to the truck. The way the crossmember is attached to the frame doesn't seem correct. Can anyone send pictures of a np205 correctly mounted on the right crossmember so I can see what's missing?

thanks and keep on trucking.

[Phuloi68]

still hoping someone might have picture of correct crossmember

[mike reeh]

hmmmm...

as for opinions, most people will say run 3.73 gears.. you will sacrifice a little mileage/highway speed compared with the 3.08's but the 3.73s will be much better for hauling, plowing, etc etc. especially with an oversized tire.

im not really sure what you want to see with regards to the picture... the way the crossmember attaches to the frame?? Well the crossmember should have 2 bolts on each side and mount to the bottom of the frame rail. SOME crossmembers had an extra peice that went up and mounted to the top of the frame rail also (4 bolts per side) but usually not.

now if you think you have the wrong crossmember, I could get you some pics of my np205 crossmember.. im 99% sure its the same as the np203 crossmember.

give a little more details.. can YOU post some pics of your setup?

-mike

[Phuloi68]

Mike, thanks for the opinion. Sounds like the 3.73's are what I should go with.
As for the crossmember. I think my truck may have originally had a 208 t/c and some one put a 205 in. I see what appears to be the original holes in frame for the 208. When the 205 was put in they drilled one hole on each side and that is all that holds the crossmember in. The crossmember seems to be correct for the 205 adapter. I have seen a 79 truck that has a 203 t/c and the way the crossmember is it it has several parts. There are 2 braces going from one side of frame to the other with a plate connected to each. Looking from the side of truck it kind of resembles the letter H. Also, there is a rod going from side of t/c to back of engine (mine doesn't have this).
It just seems like what I have is not the complete setup to have transfercase installed properly.(I will drill second holes for bolts)
Truck has excessive vibration and I think this has alot to do with it.
I don't have the necessary equipment to take pictures to show you.
Thanks for your help.