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godtool
03-29-2010, 07:34 AM
I drew a sketch below of two t-cases, a divorced np205 t-case behind a stock gm np205. I would tilt both cases so as to use the front output shaft of the rear divorced t-case for the front and rear driveshafts. I figure I can rotate the np205 on the back of my sm465. That way neither case is below the frame rails. I'll cut a hole in the cab to fit over the t-cases. I have a short ds with a slip joint I could put between the two cases or would just a ujoint suffice?. I'd have a short rear ds to the rear diff. I was going to try this in a stock 4x4 pick-up truck with no susp lift. It is just going to be a slow go trailer queen. I'm not into fast rock crawling (as of yet) Anyone ever try this? Any other ways of joining np205's together?

http://i65.photobucket.com/albums/h213/godtool/tcase1.jpg

theborges
03-29-2010, 10:13 AM
leave both intact and then shave the shift pin so you can engange the first tcase front output only, use that for a pto then 2nd can power the front and rear axle. would take alot of room to do that but if you got it would be pritty cool

tchevy
03-29-2010, 01:59 PM
use a 203/205 combo.

m j
03-29-2010, 07:13 PM
dunno what that is but it aint a 205
to join two 205s together you need the second one to have a 32 spline female chevy input
the output of the frnt one is 32 spline so it plugs right in to a 32 spline female input
all you need to do is make the adapter and clock the cases so they dont interfere, use a ford ds drop and a chevy ps drop will get the clocking done easy

rmiller026
03-29-2010, 08:21 PM
I unno we have a monster truck that has a married 205 going into a divorced 205 that goes to a divorced 205 that drives it

Troy
03-29-2010, 08:36 PM
if u want easy and cheap

see how i did it, pages 4-9 i think

http://www.funinbc.com/forum/showthread.php?t=83106&page=3

4skin
03-29-2010, 10:17 PM
that almost looks like single speed 70s ford transfer case
no low range hard to tell

godtool
03-30-2010, 08:08 AM
Troy, awesome truck you made there!! I don't expect to do nothing like that. I really enjoy seeing some fine work with lots of attention to detail. Can you post a side underneath pic of the 2 t-cases all hooked up with the driveshafts one day. No rush...

godtool
03-30-2010, 08:17 AM
leave both intact and then shave the shift pin so you can engange the first tcase front output only, use that for a pto then 2nd can power the front and rear axle. would take alot of room to do that but if you got it would be pritty cool

So the front t-case output to front diff would be a pto? right? I found a perfectly good shorty ds at the dump, spline is mint!! Still new, too bad a few caps missing off perfectly still ok u-joints. I'll shorten it up like Troys. I'm just thinking right now. The divorced t-case pictured I was told is a IH case. Its bigger than my chev np205, again found it at the dump. Seems to shift good, 2.5:1 ratio, I'll take it apart before I use it to see why it may have been left at dump. I think some parent threw out his kids toys left at home....;)

Troy
03-30-2010, 09:57 AM
Troy, awesome truck you made there!! I don't expect to do nothing like that. I really enjoy seeing some fine work with lots of attention to detail. Can you post a side underneath pic of the 2 t-cases all hooked up with the driveshafts one day. No rush...


there should be a couple pics in there where it shows the short driveshaft connecting the 2. its a simple setup.

those are old pictures and the direction of the project has changed quite a bit.

godtool
03-31-2010, 08:30 AM
Troy, thought alot about your Ford project yesterday. Do you own a tv or you just addicted to fabricating? :D I really would like to know how many hours you spent on that rig each day on the average. Were you able to work on it at your place of work? For starters I have a choice of using an 81 Chev pick-up (9 leafs in rear) or 1980 pickup (4 leafs in rear). Less leafs better flexing I say. Remove the sway bars etc. I was simple going to remove the box, and entire front clip for clearing my 39" tsl swampers so no susp lift period. The 80 chev has 3:42 gears and the 81 has 4:10's in rear and 3:42's in front. Put the worn out tsls on the front and good ones on the back and the sppeed\cirumference of tires may work out:p . Maybe narrow the rad support and cut the hood in a jeep style taper. Definetly make it trailer rig till the trailhead. So as for connecting the 2 t-cases and shortening\lengthening my driveshafts, can you give me some tips on welding and balancing these ds's in my garage. I got a mig 160 and a neighbor thats an expert welder. I guess balancing is not to important for the trail.

Also any recent pics of your Ford?[36]

My other option is to put my cj8 scrambler on my jimmy frame but I don't think there is enough room for two t-cases and to have it fabbed up by May Lonhg Wknd.

Troy
03-31-2010, 02:15 PM
ok so for getting the driveshafts trued as close as you can get it in your driveway you need a dial indicator with a magnetic base or some sort of base that can be clamped or held down to a part of the truck.

first find your length from u joint centre to u joint sitting at ride height. then measure the slip yokes you have and find out how much linear travel they have. for example if your rear slip has 6'' travel you will want to maybe split it in half, say 3 inches compressed, 3 inches for extension during the suspension cycle. bolt the driveshaft ends in place, mark it out and cut the driveshaft tube. make sure you have accounted for slip yoke travel. measure a couple more times before you cut.

then you have to 'phase' the tube yokes. basically have them lined up the same way.

put a tack on the tube yoke to the driveshaft, put ur dial indicator on something solid, rear axle, tcase whatever is closest and spin the driveshaft by hand, you will see the dial go around a couple times. take a hammer and fine tune it from there. i have gotten some within ten thousandths of an inch. others within 40 thousandths.

another tip. if you can, do not cut the splined yoke end from the driveshaft tube. it is more difficult to true up. cut the tube yoke end as its smaller and easier true up.

your gonna have to put a couple tacks on once u get it close and then keep spinning and putting more tack welds.

dont know if you know this or not but when u zipcut the driveshaft tube yokes out, dont cut all the way through, its a socket weld from the factory so just cut about 1/8'' through the weld all the way around and hammer it out. look for cracks in the cut to make sure you cut enough.

ive done lots of driveshafts this way and they are good up to 150 km/h

4skin
03-31-2010, 08:26 PM
[36] done them same way
just thought i would add make shure you ground to drive shaft
so ground isnt going through bearings in diff or transfer case
it can weld bearings[cheers] [cheers]

godtool
04-01-2010, 07:51 AM
Sounds good! I'll post some pics in the coming weeks when I start this.
[36]

Troy
04-02-2010, 12:46 AM
i hope that made sense. let me know if your confused