NP205 Input/Output Question

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NP205 Input/Output Question

Postby matthewh » Sun Apr 12, 2015 5:19 pm

I'm working on finishing up rebuilding a dual rear output NP205. In the process of buttoning it up, I double checked to make sure everything turns as it should, no noise, etc. My question involves the input from the trans. I thought the input turned at a 1:1 revolution with the output in high range, but mine doesn't. It's more like 1-1/4 to 1-1/2:1 to the output in high range.
Never thought to check that before I started, so I have no base line to go by. Anybody have a spare np205 they could double check for me, or know off the top of there head?
Thanks

Edit,
In building this case, I swapped in a 27 spline input, running the original 32 spline upper rear output, as well as the np205 idler gear. I swapped in the front and rear output out of an np200, which are 10 spline, as well as the 2wd/4wd shift fork and rod. Everything turns free, just seems like it's not 1:1 in high range
'93 W350 5spd Getrag, 4.10 gears, 83k miles and counting, Mods: LPPP AKA Ma Dually
'54 Dodge M37 6.2/700R4/205, 5.89 gears, WC rear axle
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Re: NP205 Input/Output Question

Postby matthewh » Sun Apr 12, 2015 7:59 pm

So I messed with it some more, found out it was stuck in low range. The NP200 doesn't use a small gear on the output shafts like the 205, so even though high/low shifter would shift the upper rear, the lower stayed in low.

After swapping gears around, I found the front 205 output, if swapped into the input position, gets me high and low on the outputs, which is what I'm after, but I can't find a 27-32 female coupler, plus, being an output shaft, there's no snap ring groove, and there's threads to contend with.

I'm gonna mess with it some more, still think I can get it to work. Being the input is a fixed gear, I need to figure out how to work around that, as I need that small gear on the input to float when not locked in.
'93 W350 5spd Getrag, 4.10 gears, 83k miles and counting, Mods: LPPP AKA Ma Dually
'54 Dodge M37 6.2/700R4/205, 5.89 gears, WC rear axle
matthewh
14mm rotor
 
Posts: 633
Joined: Mon Feb 18, 2013 3:07 am
Location: Boyne City Michigan

Re: NP205 Input/Output Question

Postby burnt_servo » Sun Apr 12, 2015 11:00 pm

like you found out , it was in low range .....

all the 205's I have seen are 1:1 in high range and almost 2:1 in low range ( off the top of my head it is something like 1.95:1 ) .
'93 w250 .... stock ...
curently removing the dead moose parts ....
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