What to do....

[Metal Twister]

I have a good friend who will be retiring in a few months. He has a 1990 Chevy work van that he wants to donate to me. The van has a fairly new throttle body 454 with a newer 700r4 tranny. It has a 14 bolt rear but not sure which one it is or the gearing at this point. All the stuff would transfer over to the 77 Blazer ie. the radiator, trans cooler, etc. Im not sure about the fuel tank at this point. The motor in the Blazer is tired and cant seem to hold its fluids. Im just waiting to grenade the thing one of these trips and to be honest I don't want to even fool with trying to find the leaks. Ive changed everything out including the rear main seal, one piece pan gasket, new fuel pump gasket, valvecover gaskets, even a new oil pressure sending unit. I'm sure I can find a place for the 700r in on one of the hot rods. But what do you guys think about hooking up the 454 to the TH350? Should I be looking for a 4x4 700r or a 4x4 TH400? I'm really wanting to get the 454 in the rig then I will have no excuse not to build my Expo trailer that I have been dreaming about for several years now. Any thoughts or ideas on a tranny swap? Wisdom from your experiences?      

[84sr5]

That would make an easy swap but keep in mind that the TH350 would be you weak link in your drive line.It just depends if you can go easy on the go pedal until you can upgrade to a TH400 or 700R. How many miles on the van?
I would say go for it, get the swap done drive it and look for a replacement trans at your leisure, not when your in a bind to get it back on the road. You know the 4X4 swap meet is coming up 10/22, you might just find what your looking for there.That would make it a no brain-er!

[Metal Twister]

You know the 4X4 swap meet is coming up 10/22, you might just find what your looking for there.That would make it a no brain-er!

All good points! The swap will be down the road a few months so I can finish off the 350 in the next few trips. I dont think tail shafts are interchangeable. I dont think you can turn a standard 700r into a 4x4 version can ya?

With a little research it says that a np208 or 241 will bolt right up to a 700r. Hum, wonder which tail cone I will need to use? 

[Chief Gunner]

From what I have read, you could convert a 2wd 700R4 into a 4wd 700R4.  The shaft and tail cone would have to be swapped.  Not sure if it is worth the effort, but I am sure will a little research, you could find a trans that would work with the 454.  Like what was said before, I would wap the engine when you are ready to do it, and start looking for a trans that will work for your application.  I think a NP 208 transfer case would work great.  That is what I would like to put in my jeep.  I really want to get rid of my NP 228.

[moorehouse77]

2wd 700r4 can be converted to 4x4 but you have to tear apart the entire tranny to change out the tail shaft.  Should get a 4x4 th400.  Can't break them and they arent all that pricey.  Have to put a bunch of money into a 700r4 to hold up to a 454 pulling a trailer around and running slow trough the rocks with an MT behind the skinny pedal.  Just my 2 cents.


Dave.

[Metal Twister]

Im not sure what 700r is in the van now. I know it is a 1 ton van and is hauling at least 3 tons of    regularly.   

[moorehouse77]

Year???

[Metal Twister]

1990

I also found this...  http://coloradok5.com/forums/showthread.php?t=256595

[moorehouse77]

My understanding from a recent discussion with a tranny tech is that the 700r4's made after 87 are the best ones.


Dave.

[DavidWymore]

I have a burned up 4x4 R4. And a 400 I think is burned.

400+205 is terrible gearing. 700+208 is good gearing, but weak, $ for a good 700.

If you want gearing and affordable reliability, go manual.

Dodge 241s or Super Duty ?272s? are pretty beefy.