NP231 doubler / crawlbox

right from the horses mouth (Behe) .......100$ a pound.
23# is all that $ saves us, the rest (doubler) is moot cause it's an add on to everything, now that 23# savings could negate the weight of that add on. but in the end we're buying 23#.

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midnights knockin that down to about 75$ a #, maybe?.

I don't mind spending the money when it's worth it but for a measly 23# IMO it's not even close to being worth it. I'll be interested in hearing what your weight is for just the case.
 
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I'm liking where this is going too. I might look for a 205 case fer cheap, just to have it around. Twin sticks and a crawl box is what I NEED for the varied you're of situations I can get into. If I can do it with a cheap 205, cheap 231, and a few bucks for the eco box.... I'd be money ahead probably when I did something different with my 241OR
 
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If I were to run an auto trans I would go ford 205/Blackbox doubler. 5-1 is plenty low with an auto and you get to keep the stock low range. NWF box has a nice finished look that the other doubler options are missing. But it comes at $$$$$$.
 
Went back and read where I'd found the lengths of a crawler box (231)



And you're using your conversion rate backwards. $1 US = $1.20 Can so a $750 part in Canada is $592 in US.

I was in Germany at one point where the exchange rate was $1 tp $4 German marks. So if something cost $24 German marks it was $6 US.
i measured the case face of the input, from there to center rear output is 12.375" + the 7.875" you came up with leaves us at 20.25" or so.

did manage to get the front output side broken down n out yesterday at lunch. so far everything looks great. the big bearings came out both sides without issue. i got the tail housing off also, that open speedo port is where the water intrusion was, the tail casting needs cleaned and it'll require a new bearing and seal there. next is to free the shift rails, that'll allow the other side to be pulled (you can slip the shift fork on the other side, this side needs it freed).
 
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bare case is 52#. i left the PTO cover on, it's part of the case.

so next is clean it up a bit and see what i can hack off.
 
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ok, so i'm kinda committed to some extent here,
so i went ahead and ordered up a new gasket & seal kit, a new pinion nut w/star washer, and the twin stick shift rails w/new balls, springs, roll pins and detent pressure adjusters. Bronco graveyard had the best prices.

didn't get time to mess with the case today, but did get all the internals and bearings cleaned in a naptha bath and inspected.
the bearing i thought looked like it had rust on it was just discolored gooey old lube, it's fine. even the tail housing came pretty clean inside. i think it's all good enough to reuse, no signs of hard wear. hell, the guts look like new parts now.
the aluminum seal retainers are oxidized and kinda look like poo, gonna see what a wire wheel does for the finish.

i'll try and get a few pics tomrw
 
doesn't look like much stripped down, 6" long and 18" wide. got the inside pretty clean today, need to remove the PTO cover and it'll be ready for the saw.
not happy with the looks of the aluminum bits , but IDK if i hate it enough to spend $ for something i'll never hope to see very often.

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made a few cuts today, they cut the lights off on me b4 i got pics, so Mon after some clean up grinding.

i took all i could without breakin into the case, it's was almost 2# of material. taking the rest of that boss would only net another 2#, not worth crackin the case for. now if room becomes an issue then maybe it's a venture to pursue but right now there is now reason to push further.
this is basically what i took off.

and the parts i ordered arrived today.

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case is cleaned and ready for new paint i took almost an inch off the crest of the boss. with the case set level it's a 1.25" difference.

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see those 2 oil plug holes in the case? see how they are now down very low if the case is flat, either it has to be filled b4 install or it needs a new fill hole up higher, clocked flat those both become drain plugs.

northwest fab does offer a PTO cover with a fill plug, but that also assumes it's not goin truely flat or it's in the bottom too. these cases are meant to run with that driver side drooped down a bit and that boss would be pulled down away from the body in the process.
at least thats how it looks right now.
 
How did you make the cut?
the shops vertical band saw, went through like butter. that way everything is squared off those flat faces also.
a good 1/2" off that boss is angled F to R if the case is sitting as flat as it can upright , the center chunk kinda shows the slope.
 
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