NP 205 question

[85 Jimmy]

I was cleaning my 205 getting it ready for a rebuild and paint and looked at my cover on the back. It has this bump near the middle and a hole on the inside like it's an oil hole. The date tag on the PTO cover says it was made in 84'.
I remember reading on here or pirate that if the case has that then it's a syncro'd case. I plan to use this for a doubler, will there be any issues using this case? Also, are there any differences in rebuild kits that I should know of before I buy one? It had a slip yoke on the rear, I already have the stuff to convert it to a fixed yoke, can I go ahead and do that or will I run into an issue?

I'm probably over thinking this thing, just curious why some had it and most don't.

 

[85 Jimmy]

And another thing, how in the world do you get in the case with a hammer and punch to get the roll pins out of the shift fork/shift rod? Do you have to be a magician?

 

[nvrenuf]

That is indeed a syncro'd case. They're ok but if you ever want to do a 32 spline front shaft conversion you'll have to replace everything from the fork down.

Not sure on your roll pin question.

 

[Hogback Fabrication]

That NP205 works fine for a doubler. The main downfall to the synchro case is that you can't upgrade to a 32 spline front shaft without getting a non-synchro case for parts: the front output, shift fork, shift rail, high and low gear, etc. are all different.

Shoot me an email at [email protected] and I'll get you our instructions for changing out shift rails.

 

[nvrenuf]

Oh the rebuild kits should be different or all inclusive because the bearing in that cover is different at well as the shift fork design.

 

[85 Jimmy]

That NP205 works fine for a doubler. The main downfall to the synchro case is that you can't upgrade to a 32 spline front shaft without getting a non-synchro case for parts: the front output, shift fork, shift rail, high and low gear, etc. are all different.

Shoot me an email at [email protected] and I'll get you our instructions for changing out shift rails.

Sent

I probably won't change to a 32 spline front right now. IF I ever get to a place where I can actually wheel and IF I end up breaking the front output shaft, then I'll look into swapping it out.

 

[85 Jimmy]

Shoot me an email at [email protected] and I'll get you our instructions for changing out shift rails.

Thanks for the instructions! I got the shift forks out.

 

[sweetk30]

http://coloradok5.com/forums/showthread.php?t=253000

pic by pic

step by step .

and now is the besttime to upgrade to a 32 spline front and the correct parts to convert from the syncro front .

 

[85 Jimmy]

http://coloradok5.com/forums/showthread.php?t=253000

pic by pic

step by step .

and now is the besttime to upgrade to a 32 spline front and the correct parts to convert from the syncro front .

I have your thread book marked and will be using it when I'm putting them back together. Right now all my 203 apart and 205 apart and the parts are in seperate boxes for each. You don't show how you got a punch in to punch the roll pins out or back in. I thought you knew magic or something.

*edit* I looked at it again, you can see the roll pin in the 2nd picture on post 15

 

[85 Jimmy]

So without upgrading to a 32 spline front output, would you triple stick it? Or will be doing front digs be too much for the current front output to handle?

Loking at this link is making me think I can grind my shift rails myself. If I were to triple stick the doubler, or twin stick it as just a 205.
http://coloradok5.com/forums/showthread.php?t=173938&highlight=shift+rails

 

[nvrenuf]

With respect to front digs, I'd be more concerned with the axle shafts. I would imagine the "bind" created during the turn would be more destructive than the torsional force on the front output.

I didn't grind my rails on my 205 because I was worried about breaking axles. In hind sight I wish I would have because I now I'll have to disassemble the case to do it.

 

[85 Jimmy]

With respect to front digs, I'd be more concerned with the axle shafts. I would imagine the "bind" created during the turn would be more destructive than the torsional force on the front output.

I didn't grind my rails on my 205 because I was worried about breaking axles. In hind sight I wish I would have because I now I'll have to disassemble the case to do it.

That's the reason I'm thinking about going ahead and doing it. I already have the case apart and the shift rails are actually in my lap right now.

I should be ok on the front shafts. When I put my Dana 60 together I told my wife that she'd be able to drive the truck and not worry about breaking it. So I put Yukon 4340 chromoly shafts as the inners and the same 35 spline outers.

The only thing that may hold me back is that from the sound of it, if you grind the shift rails you have to twin stick the 205, that's an extra $100 if you triple stick a doubler. I guess with as much money as it costs to put a doubler together $100 isn't a whole lot.'

I don't want to put this thing together and then wish I would have done it later on.

 

[Hogback Fabrication]

The front output shift rail is different on a synchro case, be careful modifying them as I'm not sure they need to be modified like a normal shift rail.

 

[sweetk30]

i recently modifyed the 205 for a friends truck .

when i bench tested the modifyed rails i was sure i had it .

got it all together and had to pull the 1 rail out and do a bit more.

if your swaping to non syncro or have worn seal areas on the rails and want twin stick just buy the new rails and be done with it faster and better.

my friend was also glad i twin sticked his 205 . he has a spool in the rear and its a lot better to turn tight off road with the rear in N and the front in drive with his still open front.

 

[85 Jimmy]

I've never even messed with a 205 before this one, much less modified shift rails, so maybe I need to do some more research before I start destroying my stuff. What on the front shift rail needs to be modified?
After reading the thread I posted earlier and looking at the pictures, I was under the impression that the rear shift rail was the only one that had to be modified?

Here are the shift rails out of my 205. I thought I'd just have to cut/grind the spot next to the detents on the rear shift rail so that the "flat" would be extended to the neutral position, then add the ramp like it is stock. Then cut/grind the rear shift rail at the end so that there isn't any material in the way when you shift it that way.

Here's the picture from the thread I posted. It looks like this is taken after the rail has been modified.

I'm reading on Pirate that people grind the neutral detent on the front shaft so it's the same depth as the high and low detents.

Maybe I'll take some measurements and someone can confirm that the rails are different on a syncro case like I have. I'd hate to F$%k mine up and then not be able to get replacement without swapping all the front internal.