Time to go 4x4, build plans and parts checklist

[Greg5OH]

Hoping to close on a new house in next few months, no plowing up in the country, so I need that 4x4 going!
This is for the truck in my sig.

Im going divorced np205 because theyre cheap, i got the length, and i dont want to pay 600+ for a 4wd zf (i do have a 1356 tcase sitting at home though..).
I dont like ho high the 1st gear is in the 2wd trans though...Starting with a load up a steep grade isnt nice.

parts list:
Dana 60
-need to box the frame somehow up front, just fab some plates and weld?
-V code springs?
-id liek to be 2" or so higher than stock 4x4, so shackle and hanger flip?
-currently have an open rear end, cant be having that. Going dually so a nice 3.55 LSD dually rear end would be good. Dont need to do dually yet, but an LSD is mandatory.
-driveshaft, and all necessary linakge.
-hydroboost conversion while im there
-hopefully turbo it while the front clip is off

now...I do want a GV, with that I could do 4.10s and 35" tires (I do alot of highway)
Im assuming its easier and better to do the GV while im doing everything else?

Im hashing out ideas so please bear with me.

The truck doesnt tow often, but want it to tow WELL when it does. Main purpose-winter snow machine, go anywhere and not get stuck.

Listening to all comments and ideas!

 

[laserjock]

There was a guy that did this to not too long ago, less the divorced case. Can't remember his name to save me. It was a two tone tan and brown truck I think. It was a good thread on what you needed to do and had all the measurements for locating spring brackets and such. I think he even went with the super duty springs.

 

[kuskoal]

Skip the GV for now. The zf5/205 combo would be great with 4.10 and 35" tires spins around 2000 rpm at 65 mph. You could add it on later. My rig with 37" tires and 4.10 is almost too low for highway at 1800-2000. Pushing a jacked up brick suuuucks, could only imagine towing something bigger than an M105 trailer

 

[franklin2]

Yes, if you have the zf why use the GV? If you are set on using the GV, use it with a t19 4 speed. A 4x4 t19 would be cheap enough, and you could also use the 4 speed flywheel and clutch and not have to worry about the DMF. Then the transfer case you have laying there would bolt right up. The conversion would move along much faster doing it this way, and you should be able to find factory driveshafts to fit this combo without having them made up.

 

[Greg5OH]

i want the GV to split gears, too big a rane between them, and im runnin empty 90% of the time, pointless to be up at 2000 rpm, I can save a bunch of fuel with a double OD and cruise at 1500 rpm. But thats nice I can add it later, so I shall not worry about that for now.

T19, then gottt get flywheel clutch etc, thats all too much. I have everything I need already bolted it, sans Tcase. A divorce Tcase also seems appealing to me for some reason, like that Modular setup. I just have it in m yhead that its going to be quicker cheaper and easier..."easier"

Im going with a 4.10 fornt end because they are more abundant than 3.55, and eventually want 35s. Right now I have brand new 31s on it, I can try to sell them down the line.
Also with the RSK, I want to do it so I dont have to run a block under the springs.

Also having the rear higher than the front is very important for looks IMO. HATE droopy *****.

laser i do remeber skimming through that thread, going to find it and get familiar with it.

Im budgeting about 2k to do this. A u pull yard I know has front axle complete for 160 (regardless of what it is) trannies for 75, tcase 50 bucks. The d60 trucks are rare but they do pop up.
Will keep my eye out and probably just cut the whole front end off and load it into my bed (sans engine...unless its an idiT...rare).

 

[franklin2]

I am already around 1500-1800 rpm at speed with a zf, 4.10's and 35 inch tires. I am not sure you would want to go any lower, I am not familiar with MI and how flat it is up there.

I don't know why I said stock driveshafts would work, you would have to get one made if you used a GV. Have you priced getting the 3 shafts made for the divorced setup?

 

[Greg5OH]

Thats excellent rpm, key are the 35s.
Wheni had my rear DS made it was 180 bucks.
Figure about 500 for the 3 shafts (the divorced one is just a fixed and flip yoke together, no shaft inbetween)

 

[Greg5OH]

Im also wondering what kind of brackets I can buy new instead of having to cut off a donor frame. Time is money and I dont want to spend 2 weeks cutting drilling and grinding off old brackets.

 

[laserjock]

This will be a good read for you I think.

http://www.oilburners.net/forums/showpost.php?p=752026

I finally found it.

 

[bookite03]

I'm running a 6.9/Banks Sidewinder backed by a ZF5/BW1356 T-Case and GV OD. Rolling 4.10's and on 35's...more currently doing some experimenting with 37's.
The GV isn't really setup to split gears, it requires certain hydraulic pressure to properly engage when shifted. They recommend not engaging the unit unless you're above 45mph.
With that said and my above combination on 35" tires @ 55mph 5th gear + GV engaged (so double OD) engine is turning 1450rpm. Pretty low and useless unless its flat-land bobtailing. 65mph turns right about 1750rpm with the same combination.
However, it can be noted I managed roughly 21mpg on a 200-mile round trip averaging 65-70mph.
The 37's almost make the GV useless in my application. On the highway you cant obey the local speed laws and maintain enough engine rpm to keep the egt's down and power needed. In 5th gear + GV engaged I'm doing something like 75mph at 1700rpm. However, the 37's do lengthen out 1st gear starts nicely for in-town driving.
I will say, a nice feature of having the GV is towing in 4th gear + GV engaged (4th-over) I spin the same revs as 5th gear (same OD ratio in GV and ZF). Having a much stronger combination without worrying about heating up and smoking 5th in the ZF towing, also get more friendly engine rpm for an attempt at better fuel economy.

 

[LCAM-01XA]

A few thoughts:

1) regarding brackets - if you're doing the 2.5" PMF RSK you don't need any factory-style hangers for the very front of the frame. The hangers under the cab mounts (where your shackles will go) can be bought new from Sky, theirs are actually designed just for that purpose and have the pivot hole 3/4" forward as compared to factory hangers to help with shackle angle. Realistically tho that's only noticeable if your frame was already drilled from the factory, which it isn't - you'll be drilling your own holes which leaves you with some freedom for locating the hangers. AFAIK there are no other aftermarket manufacturers who make these hangers in either factory or altered geometry, so prepare to hand Sky $150 for theirs.

2) regarding driveshafts, try getting yourself two factory rear shafts from reg-cab long-bed fixed-yoke trucks. That would be '80-'89, possibly up to '91 but that's generally BW1356 territory and those tend to be slip-yoke cases in the RCLB trucks. The idea is to place the NP205 in such a location along the frame rails, that you end up with front and rear shafts of equal length, this way should you blow a rear u-joint for whatever reason you just pull the front shaft on the spot and swap it in, no downtime for truck then. There is no rule saying the shaft between the transmission and the t-case has to be essentially just two yokes welded together, you can make it longer.

3) regarding transmission gearing - a 4x4 IDI (S42) ZF5 will likely have the same lousy 4:1 first gear as your current 2wd one. So there is no real benefit dropping your current divorced t-case plan and going with a factory 4x4 "married" setup. Supposedly the S47 model of the ZF5 does come with 5:1 first gear even in its PSD flavor, but I have no access to one to confirm it by reading the tag on its side. Alternatively you can get a gasser transmission and swap guts from it, this will give you a 5.72 first gear that's quite useful for getting heavy loads moving uphill. Or you can just keep your current transmission and shift her all the way into 5th with the 205 in low range, then when you're at the top you can stop and shift the 205 in high range and start of in 1st again. That's what we do with our Jeep from time to time, the 205 is only a 2:1 case anyways so even in low range she's moving at a decent speed once the transmission hits top gear - in case of a ZF5 its OD while in low range is more or less equal to its 3rd gear in high range.

4) regarding to GV or not - the GV website certainly does advertise it as a true gear-splitter, however I've never really felt the need for splitting the close-ratio gears. Where splitters really shine is when coupled with a wide-ratio main box, then they can fill up the huge gaps between its gears fairly even and give you steps close to what you'd see with a non-split close-ratio box. For your consideration, here are GV's own gear ratio tables: http://www.gearvendors.com/fdrive.html However, note one very important limitation of the GV - it cannot split the 1-2 upshift. If you ever get to take a truck with a creeper 1st gear out for a drive, you'll know exactly why I'm bringing this up

 

[Greg5OH]

hmm vcant shift the np205 from lo to hi on the fly eh?
LCAM thank you for that excellent info, thats great that SKy has the complete front setup, i just need the axle and springs, and boxing the frame. 150 isnt bad at all, considering i would have to cut and drill the other ones, blast em, paint em etc.
As for gearing. well ill think about that once i have the front axle in there. most likely will be a 4.10, so I will try getting a matched 4.10 rear end and live with the higher rpm for the time being while i source 35s or an extra OD. Like I said im mainly running empty 400 miles round trip (winter commuter when i go MI to toronto) so 1600 rpm at 65 would be great.

 

[Greg5OH]

So i would need this:
http://www.sky-manufacturing.com/cgi-bin/commerce.cgi?preadd=action&key=FORD-FSSH-001

and

http://www.sky-manufacturing.com/cgi-bin/commerce.cgi?preadd=action&key=FORD-FSR-SHACKLE ?

this is all very hard without having the truck infornt of me torn down to see what i actually need lol

 

[LCAM-01XA]

Yes, those are the hangers in question, they are $115 listed but shipping is $30 more for total of around $150. When you order the hangers there is an option to add shackles as well, it's $100 more this way, but cheaper than ordering the shackles separate at $130. Get your springs first tho, the factory brick and OBS springs use 9/16" bolts but the Superduty ones may have been upped to 5/8", and you can order the shackles and hangers either way.

Also no, you shouldn't shift the NP205 on the fly between low and high range, no Ford transfer case that I'm aware of is designed that. That is not to say that you can't do it per se, but attempting it is generally not recommended.

With 35s in your future stick with the 4.10 gears. Also IMHO regearing a Sterling is a whole lot easier than regearing a D60, if nothing else the Dana requires a $300 bearing puller to do it right.

If you got other questions ask away, my memory is still pretty vivid of our last 2wd to 4x4 conversion. Oh, I didn't see the shock towers in your list, gonna need those cause when you remove the coil spring buckets you're down to bare frame. Two designs are available, earlier one uses 2 larger bolts to attach to the frame, later one uses 4 slightly smaller bolts. Of the 2-bolt design there are three varieties - stamped steel light duty, stamped steel reinforced (F-Superduty), and cast (also F-Superduty). Haven't seen a cast 4-bolt, but the stamped steel ones also come in regular and F-Superduty flavor. Any of these will work, your frame rails are a blank slate as none of the coil bucket holes will be reused.