NP271 NP273 differences.
what makes them diffrent other then the electric vs manuel?
i thought they where the same guts and case.

 

come on Joe you said they where different.
i just want to know how just to know.

 

I was under the same impression.
Bump for the morning crowd while I look it up too.

 

Any one???????

 

I know if you look at the parts diagrams for each they are the same, with a few different items for the linkage/actuation.

 

Here is the diagram, crappy, but so you can see the 271 vs 273 parts for the synchros, and then at the lower right of the pic, rather than the linkage it has the motor.

 

I am subscribing to this thread because I will eventually replace my BW1356 transfer case with, it is my intention at this point, the electronic shift NV273.

I have been told by a rebuilder of transfer cases the following, which you guys can verify or contradict:

1. A used electronic version is usually in better shape than a used manual version;

2. Since the electronic version is ESOF ("electronic shift on the fly") it has a syncro ring which smooths out the enagagement from 2-wheel to 4-wheel drive - which the NV271 does not have.

My BorgWarner 1356 tc is, in my opinion, too weak for the 7.3. So, the tail housing began to leak after 1 1/2 years and it would slip out of gear into neutral when I took my foot off the acclerator driving downhill in 4x4. When I had it repaired under warranty, the company that converted my van to 4x4 told me that the internal yokes that do the shifting had worn. 1 1/2 years later it is doing the same thing and the conversion company is out of business.

I don't like the idea of mechanical linkage connecting the body of the vehicle to the transfer case in my application. The 7.3 torques on its motor mounts, the transfer case strains on its mounts, the van body is shifting on its body mounts and, since the van weighs nearly 10,000 pounds, when you are pulling a full tandem one-yard cement mixer going downhill and using the engine to help slow you down, it is too much for the BW1356.

So, I like the idea of separating the tc linkage from the body and making an electrical connection instead. I also figure that it can't hurt to have a synchro in there between 2-wheel drive and 4-wheel drive.

I know that doing the electronic connection will require some sort of jury rigging.

 

i guess that is it not much.
thanks for the info, looks like one is not stronger then the other.

 

1356 is a plenty strong tcase, its the people that operate it are the problem.

 

Thanks for the vote of confidence Skip!

Or is it possible in my case that the torque of the 7.3L Diesel with 160K miles on the engine mounts along with the fabricated transmission support mounts which are set over a foot more rearward than where Ford designed it to support the transmission, may be torquing the linkage on the manual shifter on the transfer case such that it continually wears the plastic inserts on the shift forks in the 1356?

 

he few conversion vans ive had hey used np205

 

Eh? As also did my 1976 Econoline E250 Pathfinder 4x4 conversion van with leaf spring front suspension. The NP205 chain driven divorced transfer case was noisy but frickin' rock solid like everything else about that van.

 

205 is all gear drive no chain involved. mine have also all been coil spring fronts 85 and a 77

 

Hmmm... I will have to check my notes then.

 

NP205 is definitely all an gear driven, cast iron transfer case. I owned two of them. Including one in my '79 Quadravan, which I still have. The other was in my '79 F250, factory equipped. One of the reasons why I kept the 79 trucks for so long (20 years) is because I didn't like the BW chain driven cases Ford turned to throughout the '80's. I didn't want to get stuck (literally) with a BW1356, or a TTB front end.

Today, I'd take the NP271 case I have now, even though it is chain driven with an aluminum case, and even though I've seen photos of that case shattered in Ford trucks found on road dead, simply because the low gear ratio of 2.72:1 in the NP271 is vastly better suited for what I use it for than the relatively high 1.96:1 low ratio of the NP205. So despite the NP205 being built more bulletproof and rock solid, it is less useful, due to the high ratio in lo gear.

There are 3:1 ratio fixes for NP205 in the aftermarket, but the internal gear fixes only work on Chevy and Dodge versions of the 205, with front output shaft on the passenger side. Stacking transfer cases like the rock crawlers do is probably a bit much for a camper van.