Looking for some advice.
Here is what I have.
1977 1/2T GMC Sierra
stock drivetrain 400sbc turbo 350 and the np203.
Building a mud truck.
Have 14 bolt rear, in search of reasonable D60 front in wisconsin area.
Think I will run 5:13 or 5:38 gears
12" Springs
40-44 tsl or boggers depends on what comes around
Also plan to have ram assist.

Looking for advice on what t-case to run. Prefer to use stock trans till it breaks
Any help is appreciated.

Run a stock 205..
Good luck breaking it.. They are pretty bullet proof.

in search of reasonable D60 front in wisconsin area.

good luck with that :laughing:


i'd also go with a 205 for brute strength. but with your th350/203 combo you're gonna have to find an adaptor as well. not a big deal tho. go with 44s. :smokin:

I'd have to do some digging in my shop, but I think I have an adapter for that combo if you need one..

If your just in for the mud you can't go wrong with the 205. You don't need super low gearing 2:1 should be low enough.

I seen an adaptor on ebay for about 100 but I will wait to purchase until im certain about running stock 400/350 setup. Might look for a take out powertrain from a newer 3/4 like a 6.0l 4L80e setup

I seen an adaptor on ebay for about 100 but I will wait to purchase until im certain about running stock 400/350 setup. Might look for a take out powertrain from a newer 3/4 like a 6.0l 4L80e setup

just find an older K30 donor. this will solve 350/203's latent homosexuality issues, as well as being pimp.

just find an older K30 donor. this will solve 350/203's latent homosexuality issues, as well as being pimp.

x2 The ideal combo is a 454/400/205. But if you are going to use the 400/350 the 205 is still the best choice by far. The 2:1 will be just fine since you're not rock crawling.

If your just in for the mud you can't go wrong with the 205. You don't need super low gearing 2:1 should be low enough.

x2, you'll never break one in mud

def go with the 205. also think about holding onto the 203 you may want a doubler in the future

x2 The ideal combo is a 454/400/205. But if you are going to use the 400/350 the 205 is still the best choice by far. The 2:1 will be just fine since you're not rock crawling.

Negative. The ideal combo is 454/SM465 (or NV4500)/205.:flipoff2:

Negative. The ideal combo is 454/SM465 (or NV4500)/205.:flipoff2:

Hopefully this doesnt start a Auto vs. Standard war but HELL YEAH!

take your 400sb crank throw it in a 350 put in a nice crane rocker cam/lifters etc camel hump or alum bow tie or aftermarket high compression heads run a th350 tranny add the np205 that sounds pretty ideal =P

Negative. The ideal combo is 454/SM465 (or NV4500)/205.:flipoff2:

X2 :smokin:

take your 400sb crank throw it in a 350 put in a nice crane rocker cam/lifters etc camel hump or alum bow tie or aftermarket high compression heads run a th350 tranny add the np205 that sounds pretty ideal =P

Still not ideal.
Big blocks, manual transmissions, and NP205s.
Fawk inbred smallblocks and slush boxes (TH350s to boot) :flipoff2: