hi .. im puttin a offroad/ road truck together its got a carbed 351w with alluminum intake and double pumper edle brock carb.. and mild cam... and i was wondering.. would a aod outta my other efi 302 truck.. be good or a c6 3spd outta my carbed truck be better.. cuz during the winter i make 200 mile trips... every weekend.. and wat kind of gas mileage would i get with each tranny...

im leaning toward the c-6 but the aod gas mileage would be nice...but the c-6 is more dependable

 

You answered all your own questions just need to decide whats more important.Except for the gas millage one which nobody can answer with real numbers.

 

My vote would be for the C6 as well. Screw the mileage, put something that you can beat on and still be able to make the 200 mile drive home

 

C6 will work but that slush box wil suck up a lot of power from that small block!

bolt in a 4speed 435 or t-18, very strong, way more dependable than an auto and if you're worried about your fuel mileage a stick always helps! not to mention you still have 3 gears, just one low gear for those times in need of grunt!

if you can of course! you should be able to find 435;s all over the place and for fairly cheap!

-cutts-

 

I vote with cutts, NP 435 is tough as nails and won't rob as much power as the gooey-go auto....

 

which transfer case would you be using?
DS

 

I agree with cutts.

I love the NP-435. I did brutal things with that transmission behind a FE-390 including almost running it out of oil. If you blow a clutch in a manual transmission you can still drive out (1st) and home in 2nd or 3rd. Or if you have a dead battery, you can bump start it easy. I even bump started in reverse before (which is scary with a NP-435) going down a hill when I had a dead battery. Talk about a patch of rubber. I am not even sure how it started.

If not the NP-435, I would go C-6.

My 351w/C-6/4.10/33s 4x4 van gets 9-10 mpg and weighes about 7k pounds. It is one aerodynamic 86" tall piece of plywood, I tell you that much. I think in a truck with a 351W/C-6 you should be able to get 12 mpg.

 

I had an '85 F150 with a 351 HO that got a cam job, some head work, edelbrock intake, 650 double pumper, MSD ignition, headers and some other goodies. It was backed by a C6, and the truck never got over 4mpg. Coulda been the way I drove it, like a raped ape. Also, we put around 265,000 miles on that truck beating the **** out of it and it kept ticking till the day I rolled it end over end.

 

You can use the AOD just fine but you'll need to beef it up to be on par with the C6 (ie the internal clutches valve body torque converter, etc), but then you're looking at at a cost of a good 5-800 bucks over and above of what a basic c6 build would cost you (assuming you hasve both tranny's already), but if you don't have your heart set on an auto the np 435 and even the t-18/19's areand excellant choice as well.