Well, I was wrong. Again. My NP208 weighs 86 lbs and my BW1356 weighs 83 lbs. Both are dry and w/o shift levers on them.

 

Ouch. Any way to put those puppies on a diet? At least the power train weight will be more centered and reduce my poly bushing squeak.

 

Use helium as the lube?

Seriously, I doubt you can lighten them unless someone makes a composite chain for them, but that would probably stretch.

 

Alas! Oh well, better to be reliable than light in the dirt world.

 

Someone once told me that the 1356's are known for either breaking the tranny or themselves because they are so heavy and hang out so far behind the tranny. But, unless the NP is stronger it looks like it would have even more problems.

 

Wow, I was under by a whole 23#!
I must be stronger than I thought!

My 1356 has never been a problem, but I don't do much jumping and bashing offroad.

 

Those same cases where used in everything from the f150's up through the f350 chassis cab duallies with 4x4. Ford lightened them up as much as they could with aluminum cases and such.

The zf was a lighter tranny also, being it's aluminum with a integral bellhousing. You are going to have to balance weight versus strength, the zf is usually found in the f250 and up trucks, like was mentioned most f150's had a lighter duty tranny and of course it will be lighter in weight also.

 

Dave- I keep hearing about the ZFs being in F150's. Is this wrong? Or just everyone's preference in transmissions? I believe it will suit my demands best, but I still have to source one.

 

A ZF might have been used in a 351W powered F150/Bronco, but the 300/302 powered trucks usually got the M5OD. F250 with a 300, usually had the ZF, due to the higher GVW rating of the truck.

 

Here is what the FoMoCo 1980/89 Light Truck Master Parts Catalog says was available:

 

RL250, your power goals for the 331 will dictate which gearbox to go with.

I don't know how much an M5OD can be beefed up.
Probably not a lot, as even the Ranger guys just switch to the ZF when they break one.

 

My torque goal is almost at the max rating for a ZF. I'm shooting for 400ft-lbs at crank. I expect bhp to be around 375 or so, estated based on top end kit's gap. Early ZF transmissions were only rated to 425 ft-lbs, so anything with a lower rating will not work.

 

You could look for an s47
I think they came in '95 for the 1996 model year.

 

True, which is why I'm shooting for exactly 400. That way I can use either one. Either the S42 or S47 models will hold the torque.

 

If you're still considering a New Venture, you won't find a 3500 in a Jeep. They used a slightly different version called the 3550. I believe it was a little stronger. There was one in my buddy's TJ that he had stroked out to 4.9 with some forced induction and some other goodies. It held up great behind that and that's including but outs in a jeep.