Open up the "NV3550 to Ford bellhousing adapter" link I posted above. that has the best picture I have of the adapter plate I'm talking about. Or you can see side views in some of the pics I posted above. And I did look through the thread you posted, that guy used the same adapter I used.

It probably is the same as the "block plate" you are talking about. It's about 1" thick and has a hole pattern to bolt it to the front of the trans, a hole pattern to bolt it to the back of the bellhousing, pilot diameters to locate it on both the trans and the bellhousing, and a clearance hole for the boss on the front of the trans.

Could you make it at home for less than $250? Drilling and counterboring the bolt holes wouldn't be too difficult. The clearance hole would be a piece of cake. But you'd probably need a CNC mill to get the pilot diameters right (it'd make correctly locating the bolt holes a lot easier too). Without getting the pilot diameters right you're not likely to get the trans lined up perfectly and you'll get weird vibrations and bearing wear.

Plus you still would need to get a new clutch disk. I know, that's not a big part of the $250, but it eats into it a little.

I haven't got the Atlas yet, but the theory is that you order an Atlas configured for an NV3550 and there are no mods needed to either one.

I did read the entire thread you posted now. In step 7 he talks about modifying the Dana 20 (Dana 30 is a front axle, not a t.case). It requires changing out the t.case input shaft. Jeff's sells the kit to do that as well, for $459. NV3550 to D20 Tcase Adapter I don't know anything about that kit, maybe you could cobble something together for less. But again, these are precision parts so it's awfully hard to cobble something that'll work really well. And I decided I didn't want to spend that much money on putting a t.case with only a 2.46:1 low back in. The Atlas costs a lot more, but I almost double my crawl ratio.

 

"...modifying the Dana 20 (Dana 30 is a front axle..."
ummm, I'll probably keep gettin em mixed up, just glad I got a D44 for my frnt end! Thanks for the correction.

I guess I need some templates and dimensions. There's a machine shop in the neighborhood. He wont allow "anything cobbled up". Guess U know the machinist types? He did a $300/400 steering linkage for $80 but I gave him the parts & showed him some pic outta a catalogue. You don't have that adaptor free still? to trace over?

OK, another adapter, I'm learnin. Appreciate it Bro! Wont B long now, gunna B nice!

 

Don't tick that guy off! At a shop rate of around $100 / hour (which I think would be pretty close) I don't think you could save money over buying the Advance Adapters part. You're getting a steal!

Sorry, but I don't think I ought to give Advance Adapter's design away to help someone not buy from them. Besides, it'd be just as easy for you to trace it out from the trans and bellhousing. I'll point out that the thickness is important though, to get the splines on the input shaft sticking the right distance in front of the adapter face. Just take a tape measurer and find out how far the flanges are in front of the face on the stock trans and make the adapter the right thickness to make the NV3550 splines the same distance in front of it. The pilot section of the NV3550 is longer than the stock 3-spd, but that can be chopped off if needed.

 

Thank you, sir! Good All Around...

Sno's almost done here, month'n a wk for the hills left, I'd guess.
Hope you finish up soon, get out there & in it!

 

Wish it was here! We still have at least 6" in the yard. The piles along the street and driveway are 2' - 3' high still. The low yesterday and today was single digits, yesterday was 20, today 25. And we're supposed to get 2" of snow tomorrow. So I'm not seeing an end soon

Never-the-less, good progress this weekend. I got the clutch removed and pushed out the pilot bearing. If you don't know the grease trick, you shoot it full of grease behind the pilot, take a shaft that is a close fit in the pilot and rap it with a hammer. I had to pack it with grease a second time and repeat, but it came out no sweat.

The Advance Adapters NV3550 - Ford bellhousing adapter came with a new pilot bearing that fit the Ford flywheel and the NV3550 input shaft as well as a clutch disk that went in front of the stock pressure plate. I installed the new pilot and clutch without resurfacing the flywheel or replacing the pressure plate because I've only got about 15K on the clutch. I did use a new throwout bearing though.

I did some careful measuring and determined that I didn't need to shorten the input shaft That avoided the thing I was dreading most.

Putting the trans in was difficult only because I'm cheap and didn't get a transmission jack. I put threaded rods in two of the bellhousing bolt holes, laid under the Bronco and bench-pressed the trans up into place. Getting it onto the treaded rods let me not have to hold the entire weight as I slid it forward. Of course I was only putting it in place so I could mark where I needed to cut the hole in the floor for the shifter, so I had to take it right back out again.

The hole for the shifter was entirely behind the reinforcing rib, which was nice.

After cutting the hole the tranny went back in again, hopefully to stay this time The shifter went on with no issues. I've got plenty of clearance to the dash in 1st, 3rd and 5th, and no problems in the "back" positions either! The only thing is that the shift pattern diagram on the shift handle is upside down. I need to figure out how to get it off, turn it and put it back. The shifter kind of feels like it's a long way to the right, but that's because I'm comparing it to the Hurst floor shift conversion on the stock 3-speed which put the tranny shifter right against my knee in 1st gear. The new shifter is centered, or maybe even a little to the driver's side, so it's more "normal" than what I had. I'm sure I'll get used to it really fast.

Then it was little stuff, putting the starter back on, hooking up the clutch linkage. I've ordered an Atlas 4.3:1 2-speed transfer case, so I'm pretty much stuck until that arrives. Hopefully the t.case shifters won't be a big problem (and hopefully I won't need to pull the trans back out to get the floor cut for them!). And I'll need to make or buy a new crossmember. Then once I get the driveshaft lengths ironed out it'll be rolling again!

OK, enough talk. Now for a few pictures.

Here's a side view. You can see the back of the trans through the huge hole in the side of the tunnel (the hole was for the floor shift conversion). The hole for the new shifter is bigger than it needed to be because it overlaps with the hole for the original t.case shifter (which needed to be enlarged when I put the AOD in it earlier). The shifter is in 4th gear (center and back) in this picture.




Here is a top view. The shifter is still in 4th.




And here's a top view with the shifter in 5th I think (or maybe it's 3rd, I'm not sure)

 

I ordered the Atlas transfer case last week and was told they were 1-2 weeks out on builds, so I was hoping I'd get it next week. I was very happily surprised when it showed up on Thursday Suddenly I had a busy weekend ahead of me!

I decided to read the instructions first, rather out of character for me. I was a little disappointed by the instructions relating to the shifters. Under "preparations" it says "detailed shifter assembly instructions can be found in The Final Installation section." But they aren't there. So I'm back to my normal method of just looking at it and trying to figure out where it goes.

I hoisted the case up into place to figure out which of the four clocking options I wanted to use and found that there was only one option. Only the lowest position cleared the frame, and even there it only cleared by about 1/8"! (pics below) As with the transmission, I lifted the case into place the (hopefully) cheap way, by laying on my back and bench-pressing the 110 lb case. I don't recommend doing it that way! I hurt all over now (except in the wallet). But it did work.

Once I figured out where I wanted it clocked I had to lift it back out (more "ow"). Then I did the rest of the assembly on the work bench. It all went pretty easily with the exception of the shifters. Not having the case in the vehicle I couldn't figure out where the levers were going to end up, so I couldn't figure out what went where. I did get the basic layout understood though, so I figured I was ready to put it back in.

But first I filled it with gear lube. Boy, I'm not looking forward to doing that again when it's in the vehicle! There's no fill hole, so I tipped the case on its front and used a REALLY small funnel to pour it through one of the fittings for the oil level sight tube. That was a slow process, about a half hour for 2 quarts! Pouring oil directly into that fitting won't even be possible with it installed. I think I'm going to have to get a hose and fittings so I can "extend" it to add lube later.

Putting the case back in took a few tries (my arms were still worn out from the first time). But I eventually made it. But with the case in position it was clear that there was no way the shifters were going to work. They are for early Broncos, and are intended to come through the original t.case shifter hole, but the levers would hit the top of the NV3550 long before they were leaned over far enough to make it through that hole. I tried having them come out of the side of the tunnel instead, but then they came out at such an angle that they hit my leg (see pic below). I tried putting the levers on backward, which was better, but it puts the two handles too close together, and doesn't let the linkages line up as well.

After some interweb searching it seems that the "Bronco" shifter is really only for Broncos with the C4 trans. Having the levers come out the side of the tunnel and bending them to clear your legs seems to be necessary when using other transmissions. I'm going to see if I can return the Bronco levers and get a pair of straight "universal" levers, since the "bending" I need to do on the Bronco levers is simply to straighten them out. From my search I've also decided to go with the Heim joint linkage upgrade as well.

OK, time for pictures! Here is a picture showing how big the Atlas is compared to the Dana 20.




Here are a couple showing how little clearance there is between the Atlas and the left frame rail (and this is with it clocked in the lowest position)!



(I added the arrows to this pic to make it more clear how it's oriented)



Looking in from the side




The "Bronco" shift levers installed correctly but coming out the side of the tunnel.




Shift levers installed backward

 

"...with the case in position it was clear that there was no way the shifters were going to work. They are for early Broncos, and are intended to come through the original t.case shifter hole, but the levers would hit the top of the NV3550 long before they we...d doesn't let the linkages line up as well...."

Yeah, don't know anybody who's put the atlas behind an NV. Kinda isolated out here in the bush at least for bronks & mods. Only get together on line 4 that. CB or if U ever talked to Chuck at BCB he's a great help (50 yrs of moddin these rigs). If U can get him out of the garage to the phone! I bet there's help near in CO, tho. "House o Diesel" has an atlas, U could contact him here (lght blue, not grey, horizontal bar above) if the new arrivals wont work...

 

The Advance Adapters site, Atlas Transfer Case - 1966 to 1977 Ford Bronco | Tech Vault | Advance Adapters says "The twin stick configuration for the Bronco applications PN303004L was designed around the C4 transmission configuration. There are numerous transmission options available for the Bronco’s; therefore, this shifter configuration may not work in all vehicles. You may be required to modify the shift handles to work in your vehicle". It also shows the shift levers coming through the top of the tunnel as the "stock location" and through the side of the tunnel as "custom location."

With the NV3550 (and probably most manual transmissions), the shifters pretty much need to come out the side of the tunnel. The modification to the shift handles that will make that work best is to straighten them out. But since Advance sells straight sticks in their "universal" shifter kit, I'm going to see if I can get my bent sticks replaced with straight ones. Otherwise I can certainly make it work, but sticks I straighten aren't going to look as nice as sticks that were never bent to begin with.

 

It's been 3 weeks since my last update. I've been busy, just no progress worth posting until now. I decided to build my own transmission crossmember rather than buy the Advance Adapters one for the NV3550 that needs to be modified to be used with an Advance Adapters transfer case. I also have dropped radius arm brackets which are kind of wrapped around the stock crossmember brackets, so I was afraid I'd need to modify it for those as well. As I expected, it wasn't that hard to do myself, it just took a LONG time. Since I don't have a welder at home I was cutting, marking and clamping at home, taking it to work to tack it, bringing it back home and test fitting it, and then repeating the cycle with the next section. But I finally got it done, slopped a little paint on it and got it installed today! Before you look at the picture below I need to warn you, my fabrication is DEFINITELY function before form. Some fabricators make even the hidden brackets look like works of art. That ain't me. But it'll hold together.

I did need to take the t.case back out to get the crossmember in (and out, and in, and out, and in...). So after getting the crossmember buttoned up I bench pressed the t.case back in again, I think for the last time I had talked with Wild Horses (where I ordered the Atlas) and they had Advance Adapters send me a pair of straight sticks I also ordered the heim joint linkage upgrade after reading a few comments on line.

The straight sticks are a lot shorter than the "Bronco" sticks. They may end up looking kind of funny once I get the floor cover plate figured out and the boots installed. And the left stick (for the front driveline) is still pretty close to my right leg, especially when the front is in low range. It's not too bad in neutral and it's great in high. I could try to adjust the linkage to have the levers lean further back, but I think I better wait until I see where the floor plate ends up. In the mean time I'll try it where it is. I think it'll be OK.

Speaking of the linkage, I didn't do much with the original linkage, but it does seem better with the heims. No slop, but no bind either. I'm looking forward to trying it out!

OK, time for pictures. Here is my work of... well, not art, that's for sure. This is in the yard after being painted.




And here it is installed. I used a transmission mount from a 2002 Jeep Wrangler (the vehicle the tranny came from) and built the crossmember around it. I bolted the left end of the crossmember to the 4 holes that the original crossmember bracket bolted to. And I used the original bracket on the right side, bolting the new crossmember to it. The front driveshaft will go under the crossmember to the left of the tranny, and the exhaust will (hopefully) run above the crossmember to the right of the tranny.




And last, here's where the shifters all ended up. The t.case is in 2WD high (right stick back, left stick in the middle) and the tranny is in 1st in this pic.




I also got a couple of little things taken care of. I bought the back-up light switch connector for the Jeep. It plugged right into the tranny and I spliced it into my harness and my backup lights worked, first try!

And I ordered the Atlas with a speedo pickup, but it's a Jeep style, so the Ford speedo cable doesn't attach to it. But Wild Horses sells speedo cables with the Jeep end at the t.case and the Ford end at the speedo. I got one of those and it went in pretty easily (working under the dash was never easy, but it gets harder as I get older and stiffer and more far-sighted). My speedo was pretty far off before (neither the previous owner or I ever bothered to correct for the bigger tires). But I ordered the gear off the chart Advance has, based on my tire size and axle ratio. We'll see how close it ends up now!

I also got both driveshafts shortened. The Atlas front output is in the same place as the Dana 20, but the NV3550 is 1" shorter that the RAT, so the front shaft needed to be shortened an inch. And the Atlas is about 4" longer than the Dana 20, so the rear needed to be shortened about 3".

I still need to install the driveshafts, run the t.case vent line and fill the tranny with fluid. Then I'll tow it to an exhaust shop and get a new exhaust made for it. But I figure I've made enough progress that I updated my signature line to say that my Bronco has the NV3550 and Atlas. I think I'm still on track to wrap this up before the end of the month

 

It's back on the road! (and now off again, more on that later) I towed it to a muffler shop and had them try to figure out how to fit the exhaust in. The problem is crossing over from the driver's side. The Atlas is too wide to run a pipe past it (see pics earlier). After searching on the internet and staring up from a creeper for a while I came up with three options, none of which was perfect: above the front diff in the oil pan cut-out, between the pan sump and the bellhousing, or under the bellhousing. I gave all of those options to the shop and they picked behind the sump. Down sides are that it's right behind the oil drain plug (which could be a pain changing the oil) and that it's in the way for dropping the pan and maybe changing the starter. But it's tucked up out of the way and it's in, so that works for me!

Here's a picture




An hour or two in the driveway and had the rest of the little things taken care of and it was time for the first test drive! The engine took a little coaxing to get running smoothly (it was last parked in October), but everything worked!

My initial impression of the NV3550 is that it's more truck-like than I expected. It shifts pretty lightly, but with really long throws, and you can't shift it very fast. I remember my buddies NV3500 (basically the same trans but in a Ch*vy S10, and with an integral bellhousing) shifting more car-like. It's not at all bad, but it could be better. The other issue is that the shifter is pretty far away in 3rd and 5th especially. I might end up making a new shifter and getting it a little closer, but that's not too bad either. and it's sure nice having one more gear to shift into on the highway!

I haven't gone off road yet, but I tried out the Atlas in low range. It's slow! I can't wait to try it in the rocks. And it shifts in and out of gear a lot better than the Dana 20 did too.

So now the next problem. The last time I drove the Bronco last fall I had two problems: the throttle linkage fell apart and the horn started blowing constantly. The throttle linkage was a broken clip that I fixed last fall after I parked it (https://www.ford-trucks.com/forums/1...ner-clips.html), but I just disconnected the horn and figured I'd get around to it eventually.

Well, eventually just came. It turned out that the reason the horn was blowing was that one of the three bolts that holds the steering wheel to its hub had stripped its threads and fell out. That let the horn switch assembly tilt so it always made contact. But more seriously, it also meant the steering wheel was only held on by two bolts instead of three. And it turned out both of them were less than finger tight So it's parked until I can get the stripped threads helicoiled and get the steering wheel back on solidly. I expect that'll be early next week given my schedule right now.

 

That's some fantastic progress (from the "nuttin will stop me" school).
Admirable!
What's the shake down (off rd) cruse?

 

In July we're going out to the Black Hills for a week. It'll be the first family vacation we've had since 2010, and probably the last one ever. My "kids" are 18 and 20, trying to schedule anything around their varied schedules was impossible. And it'll probably never happen again. But my wife picked the dates and both boys committed to keeping them open. In the future I'm sure my wife and I will keep using the Bronco, but this is probably the last time for a family vacation.

By the way, all of the off-road pictures with my Bronco (and most of them with my Jeep) are from the Black Hills. This'll be my families 6th trip there, as well as one trip I took our Boy Scout Troop on (but no fourwheeling on that trip). Of course being in Minnesota it's a lot closer than a lot of options, but it's sure been a family favorite.

 

Family traditions are hard to kill AND shouldn't be!
May B in yrs to follow there'll B a "once every 5th yr" kinda think with the grandkids, who knows. Once the bronk's together the empty nesters i'll hafta keep it going, enjoy'n see what happens. I'm havin a 'final' graduate from high school nxt mo and will report back in a decade about my similar plans & 'the empty nest' from here....
I know a 50 y/o w/a 20 or 30something son who went to Sturgis in Oct for 2 or 3 yrs. a decade or 2 ago. Each contact or telephone call around August the ol man would ask the son if he wants to go again. He just took em up with the idea in '13 (after 1/2 doz refusals) and the son now wants to get back inta the tradition every yr. again... mmm?... family... kinda nice...

 

Time for an update and then a report on the shake-down run. The straight shifters for the Atlas work out pretty well. My leg kind of leans on the shifter for the front when it's in 2WD. It's mildly annoying at times, but not enough that I'm not just going to live with it. It's fine in 4-high and 4-low.

The trans shifter did end up needing to be moved farther to the left and back. But rather than make a new one I just bent the stock one. With a lot of heat and a big hammer it went pretty easily.

Two single stick shifter boots from Wild Horses worked a lot better than a single twin stick boot with the sticks coming out of the side of the tunnel. And a trans shifter boot for a '73 - '76 F-Series worked for the trans.

I reinstalled the hand throttle on the trans shifter (it had been on the t.case shifter before the trans/t.case swap).

I wrecked the piece that had the shift pattern on top of the trans shifter trying to take it off. But I got a new one at a J**p dealer. And I put it on right side up!

'Nuff talking, here're the pics. The trans is in 1st (left and up), and the t.case is in 2-high (left stick in center, right stick back) in these pics.

 

And the shake-down report I promised. I love it! My biggest concern was that I'd end up hunting between low and high range a lot on the trails. I did a little, but not too much and the t.case shifts easy enough that it wasn't bad when I had to. I did end up running in low range 5th a fair amount, but hey, that's what it's there for. And the lower 1st gear (4.01:1) meant I didn't have to grab for low range as soon as I might have.

But in 1st gear-low range it's a completely different vehicle! Where before I needed to keep the engine rpm above about 1200 (3.4 mph) to keep from stalling too often in the technical sections, now it will idle at 800 rpm, which with the lower gears is 1.1 mph. Energy is proportional to the square of the speed, so that means I'm hitting the rocks with one tenth of the energy as I used to. And I stall the engine less doing it! That's HUGE! I can't begin to tell you how much I love this set-up off road!

On road it's pretty nice too. As I said before, the NV 3550 isn't as fast- and smooth-shifting as most car trannies, but it's not bad. It grinds often going into 2nd, but I start in 2nd, so that's rarely an issue anyway. Even with the overdrive I could still pull a taller axle ratio. 3.55:1 might be ideal for the street, but the 4.10s aren't bad, and I'm not giving up any of my new crawl ratio!

OK, picture time! This first one is on a hill that was so steep it was difficult to walk down on foot. The low gearing made it a breeze to stay in control.




The next two are walking over some bigger rocks. Set the hand throttle up a bit if 1.1 mph was too slow and it just walked over everything I was willing to attempt (I was running solo and really didn't want to roll it or break anything important).







And yes, it's a Bronco with short radius arms and urethane bushings, so it doesn't have much front-end flex.




I finished the trip with the most damage I've ever had from a fourwheeling trip. Two crunched rear quarter panels, a broken-off antenna (and both wipers) and some pretty bad "pinstriping" down the sides. But the rust in the rockers is getting bad enough that a fiberglass tub is in the works anyway, so I didn't feel too bad.