Atlas transfer case in Cummins powered '68 Ford CrewCab thoughts/opinions needed

eggman918

Adventurer
I have recently completed a 4BT install in my F-250 CrewCab,it is connected to a '93 M5ODR2 5 speed and 3.55 geared axles with 32" tires and I am happy with the combo around
town and on the highway even pulling the trailer the trans ratios match the 4BT's power band perfectly but offroad and on the older/forest service roads I need lower gearing.
I am thinking about splurging for an Atlas 4 speed T-case with the 2.0/2.72/5.44 ratios but that is a LOT of money and I need advice/input from people that are a bit detached
from the project I fear that I might be a bit myopic at this point after over 3 years and more money than I care to think about.As I see it the Atlas would be ideal for my application
as the 2.0 low range is synchronized to allow shift on the go and it has a 2 low ability. My other option is a ZF5 for the lower 1st gear that would help some but I am limited to small block ford
transmissions unless I buy a different adapter and flywheel and the gas ZF's 2nd to 3rd and 3rd to 4th spacing's are a little wide for the 4BT. So if I go the diesel ZF route I will be out aprox.
$2,000 and have a lower 1st which would help but not be ideal. With the Atlas it will be closer to $3,500 but I will keep my ideal on road gearing and have MUCH better gearing off road and
in the mountains for both up and down hill. We chose to do the Cummins swap in this truck instead of buying a newer diesel truck so I would still be in for less cash then if we had bought a
newer rig and the simplicity of it and lack of regulation it is encumbered by are both pluses for the '68 not to mention the emotional attachment we have to it make keeping it our choice.
So does the Atlas sound like a reasonable choice? We plan to keep this truck for ever and it is what we will use to travel when we retire so we expect to put a lot of miles on it and
it will be passed on to our kids after that so it is a long term "investment".
What do you think?
Thanks, Steve.
 

redthies

Renaissance Redneck
I think:

A. You have very lucky kids.

B. $2000 for less than ideal or $3500 for ideal... Can you afford the extra $1500? If so, you know what to do.

C. You must post pics of the '68, or we won't be able to be as helpful. How can we make an accurate recommendation
without having visual aids?

D. For some reason your text is very hard to read. It shows up with a full line and then half line pattern. Confusing.

E. All of the above.
 

eggman918

Adventurer
We can't really afford either but as through the whole project we will make it work somehow.
Yes you are right I know what I need to do but it helps to hear it from people that are not emotionally involved in it.
Here are a couple of pics.
 

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bknudtsen

Expedition Leader
Nice truck!
.
If it were mine, I would drive it for a while and see where all of its shortcomings are and then go from there. Also, I would invest in the areas that will keep the truck alive and well so that it can be passed down to the kids. That means rust repairs, body/frame protection, etc... What good is a rusted out jalopy with a $3500 Atlas in it? Maybe a set of 4:10's/4.56's would be a better solution? $3500 buys a lot of diesel for trips. With that said, it's not my truck, so take my advice for what it's worth.
.
Brad
 

rockwood

Adventurer
I don't care if it has a Beverley Hillbillies look to it, it works. Just drive it, learn its weak spots and fix 'em.

Being a California truck, bet it pretty rust free.
 

rube bonet

Adventurer
What t case are you running now? Have you considered running a 203/ 205 doubler? Same end results, much cheaper than a 4spd atlas.

.
 

eggman918

Adventurer
I've owned the truck since '90 and as it sits the drive train from the trans back has less than 3,000 miles on it and there are no known weak spots,I have used ran it pretty hard over the years.
I geared it with 3.55's and installed the Cummins for highway mileage I went from 9/10 mpg to 18+ which is not bad for a 7,500 lb "brick", someday it will get body work and paint but that is not as
important as functionality to us and knowing my luck as soon as I did it someone would hit it as it sits people give it room and respect so it is fairly safe from "fools" on the road.
Eventually I will replace the low pinion 44 which is the weak spot in the drive train with a high pinion 60 in front,I have been looking for one for the right price but with 35.5" spring centers they are few and far between
The T-case is a divorced Dana 24 but I have a NP205 on the shelf,I had thought about a 203/205 but I think I would need a divorced 203 and I've been told they are hard to find but I could look into it.
My Wife is a dispatcher for county fire and they had their first wild land fire yesterday so she will be getting a LOT of overtime this summer as they are only staffed at 50% and fire season lasts till early October here.
I have time to look for a 203 or save the money for the Atlas, it runs well now and we can still use it if and when she has time off.
 
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bfdiesel

Explorer
I would keep a look out for a zf6 with a np271 mated to it. Puts your crawl at 3 mph at 750 rpm. and overdrive is a .72 for just over 2000 rpm at 75 mph.
 

05PWrockcrawler

Adventurer
Awesome truck!!! If you plan to keep it FOREVER it's a no brained to get the best parts possible to make it an even better rig and more reliable.
 

KELLEVRA

Observer
Go with the atlas eggman.......you'll be happy in the end.....it solves all your problems....we'll maybe not ALL....I still need to get that beer with ya...:friday:
 

Rot Box

Explorer
My concern is the M5ODR2. Is it up to the task of off-road driving and/or pulling the camper? Also is the Dana 24 the t-case that does not have a lo-range? If so and if you're comfortable with the M50DR2 I think that NP205 you have would make a huge difference plus it can be upgraded with 3:1 Lomax gears down the road if its still not low enough. A 2 speed Atlas would give you plenty of low gearing as well... The 4 speed would be the ultimate but I know from the Toyota dual case world there can be too almost too many gears at times and only a few actually get used :coffeedrink:--is having 4 speeds worth the price? Only you can make that call.

The nice part is the options for transmissions behind that motor are limitless :Wow1: I would personally go for a different adapter plate and an NV4500 and t-case from a 94 or newer Dodge. Strong, simple, good low gearing (not rock crawling gearing but good for everything else), eliminates the extra driveshaft and you can find them for an ok price used. If that wasn't enough it would be time for t-case upgrades. Thats just my $.02

Btw nice rig! Keep us posted.
 

eggman918

Adventurer
Thanks for all the input I knew I would get ideas that had never crossed my mind. So let me go through some of them,
The zf6/271 and diesel adapter would be a bit cheaper and eliminate the intermediate driveline and give me better low range options and the ZF is much stronger plus
the diesel adapter will give me a 12" clutch disk,but I dont think the 271 will fit between my frame rails the '67/'72 ford's are only 31" wide on the inside.

The 203/205 I think would be the least expensive way to go and the simplest install basically "plug and play", but divorced 203's not common I am not in a hurry so
I will start looking.

I to was worried about the strength of the M5ODR2 but it is the trans of choice for many 4BT conversions as it's gear spacing is ideal for the 4BT and many of the early '90's
F-150 had a much heavier GVWR than my '68 and my 4BT is not turned up too much as mileage was my major reason to do the swap VE pump,stock injectors,HE221 7w with
a large I/C so I "think I will be OK. The 4BT has MUCH more usable power than the 3904v it replaced but it all happens below 2000 rpm.

The Dana 24 is a 2 speed case with a 1.86-1 low range.

WE have 3 self service boneyards in town and lots of pickups so I will grab the tape measure and hit the yards today and see what I can come up with.
I will keep you all informed,and keep the ideas coming they are a great help to the process.
 

12husky

Adventurer
I am not as familiar with the M5ODR2, but you may be able to swap the tail housing from a 4WD version and then not need the divorced 203 to go 203/205 route.
 

eggman918

Adventurer
I spent the weekend researching my options and it looks like the most cost effective way for me to get what I want is a doubler for the NP205 I was planning to put in the truck anyway.
I found a company called Behemoth Drivetrain and their "Strong Box" planetary doubler which has a 2.71-1 ratio,they have one that fits the Ford divorced NP205 they quoted me $1,000
and they supply all that I will need to bolt it in place except a cross member to support/stabilizer but they do supply the mount for the doubler that will bolt to my cross member.
This sounds ideal for me and is VERY close to the ratios in the Atlas T/C I was looking at. I think that I can get it a rebuild kit for my 205 and a new shorter intermediate drive line
and still be in for $1,500 or a bit less! Has anyone dealt with Behemoth Drivetrain or am I the guinea pig for them? in E mails and on the phone they seemed knowledgeable and were prompt
and helpful... I hope it works out well I will keep you all informed as to how this works out and will do a thread on the install here.
Thanks for the input and support.
 

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