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miked
12-14-2000, 04:17 PM
does such a beast exist?

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Mike D'Ambrogia - San Ramon, CA
69 Custom Wagoneer - The Firetruck

Built 350 w/ Buick 4 barrel manifold, 600 cfm quadra-jet, RV cam, 10:1, Pertronix ignition,8mm plug wires
MSD coil
rebuilt TH400 w/ B&M shift kit
Powr-Lok rear end
Factory A/C
Herculiner over new floorboards
Complete rewire with American Autowire Power Plus kit
LPG/Propane install coming soon!

Kenall
12-14-2000, 04:31 PM
no
sorry.

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Ken
1966 Super Wagoneer (http://www.home.earthlink.net/~kenns9/)
'The Predecessor'

scotty
12-14-2000, 05:04 PM
find the right spicer 18 and you can swap its guts into your 20 case,or swap it right on if you find the elusive(been at the big word store again) version with the same 4" index bore.

a saturn overdrive bolts right onto an 18.plus you get some extra low range. http://www.ifsja.org/ubb/smile.gif




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scott
85 grand wagoneer
258 with motorcraft 2bbl/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

T18/dana-spicer 18 with drum E brake and PTO swap very soon
searching for offset QT rear and PTO winch

miked
12-15-2000, 02:33 AM
wow, thats interesting... how does one identify the "right" spicer 18? is the saturn o/d and electric unit (activated by switch)? what ratio's does the 18 have?

the question man

btw, thats an eclectic vocabulary you're sporting lately...

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Mike D'Ambrogia - San Ramon, CA
69 Custom Wagoneer - The Firetruck

Built 350 w/ Buick 4 barrel manifold, 600 cfm quadra-jet, RV cam, 10:1, Pertronix ignition,8mm plug wires
MSD coil
rebuilt TH400 w/ B&M shift kit
Powr-Lok rear end
Factory A/C
Herculiner over new floorboards
Complete rewire with American Autowire Power Plus kit
LPG/Propane install coming soon!

scotty
12-15-2000, 03:24 AM
both the 20 and the 18 have the "texas" shaped front mounting pattern.the 20 and some versions of the 18 have a 4" hole to index it to the tranny.when you pull one of these cases,the input gear remains attached to the trannies tailshaft,and slides thru the hole. the rest of the 18s had a 3.5" index hole that in some cases,also served as a bearing retainer.to pull this case you must pull the input gear,remove it thru the rear of the case,then the case will come off.

i have no idea what years or trannies had the 4" hole version of the 18 case.this is the only one thats a direct swap.you would pretty much just have to luck into one,i have not beenable to fid any info as to what vehicles,years,or trannies came with them.if someone else here knows,id like to have the info! http://www.ifsja.org/ubb/smile.gif

at any rate,the 53 and later cases are easy to come by,and its no big deal to swap the innards.the 18 can use a 3/4"(1943 to 1946),1 1/8"(47 to 52),or 1 1/4"(53 and later) intermediate shaft. the 20 uses a 1 1/4" intermediate shaft as well.this is why you need to use the 53 and later version.i think everything but the t14 used a 6 spline output shaft.the t14 uses a 10 spline.the input gear is different than the 20,so youll need to get the matching input gear from the donor tranny,just make sure it has the same splines as your stock input gear,so you can swap it.

hope this isnt too confusing. the end result: find a 53 or later spicer 18 off of any tranny other than a t14,and you can swp the input gear onto your tranny,and swap the 18 guts into your current 20 case.

im using a 77 t18.when i pulled the 20,im left with an input gear with 6 internal splines.my spicer 18 came from a 66 cj with a t90.the t90 also has a 6 spline output shaft. i have completed the innard swap,and now just have to bolt the matching input gear(from the back of the t90) onto the t18 and bolt it back on,just like the stock 20.

very simple.the 18 has an offset rear output,and the overdrive simply bolts to the back of the case,where the rear output used to be on a dana 20.i forget what the ratio is. the unit is lever operated.it has its own special input gear,and when the unit is engaged,simply sends the power thru the overdive gears before getting to the rest of the gears in the t case.you can select over drive,or 1:1,a plus over the part time QT that reduces low range by 16% as well.

you can prolly run your stock rear without prollems,but i intend to swap in an offset rear(from a QT rig) to fully take advantage of the offset output.ill be able to go thru deeper ruts with the same size tires than i could with a centered pig.pluss,its easy to keep rocks and other obstacles on the driver side of the rig,and not worry about them hitting the diffs http://www.ifsja.org/ubb/biggrin.gif

almost forgot-if you find an 18 case of unknown year,you can measure the intermediate shaft without case disassembly.as long as its 1 1/4 inches,it will work for purposes of swapping guts into a 20 case.

any other ques?

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scott
85 grand wagoneer
258 with motorcraft 2bbl/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

T18/dana-spicer 18 with drum E brake and PTO swap very soon
searching for offset QT rear and PTO winch

[This message has been edited by scotty (edited December 15, 2000).]

miked
12-15-2000, 03:42 AM
no more questions right now, need to digest this info for awhile and do some digging around for info on the saturn o/d.

found this: http://www.jeeptech.com/convxfer/warnod.html, and there is a general discussion about the swapping there also at http://www.jeeptech.com/xfer/d18.html.

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Mike D'Ambrogia - San Ramon, CA
69 Custom Wagoneer - The Firetruck

Built 350 w/ Buick 4 barrel manifold, 600 cfm quadra-jet, RV cam, 10:1, Pertronix ignition,8mm plug wires
MSD coil
rebuilt TH400 w/ B&M shift kit
Powr-Lok rear end
Factory A/C
Herculiner over new floorboards
Complete rewire with American Autowire Power Plus kit
LPG/Propane install coming soon!

n2ri
11-28-2007, 08:51 PM
Guys...

stop telling lies and find the facts. I know for a fact at least 2 - 20% overdrives where made for the dana 20 but companies are gone now. one did not even require drive shaft shorter. look in Nov 1980 PV4 mag. now if I can just find one of these overdrives for my 73 Quadravan:D

Mitch

Tad
11-29-2007, 05:55 AM
Blast from the past :)
This post is just 2 weeks shy of being 7 years old.

85woody
11-29-2007, 04:41 PM
There is such an overdrive cause I got one in my garage in pieces right now. It looks like a borg & warner T85-N, the one with the solenoid. I don't know who made it but it fits the dana 20.

red mistress
12-01-2007, 08:39 AM
I'm all over this thread. Glad to know there is overdrive for the 20. Didn't Advance Adaptors buy the Saturn Overdrive rights? Bet they still got parts or can whittle some up.

waynestiles
12-01-2007, 12:36 PM
If you go to the Willys tech site on Yahoo and do some searching you'll find a whole buncha of stuff on the various transmissions and overdrives.


http://autos.groups.yahoo.com/group/WillysTech

Elliott
12-01-2007, 05:21 PM
No expert here, but from what I remember on those older overdrives... they don't hold up well behind V8's as they were designed to be run behind the 4cyl.... at least the Saturns.

Herk
12-07-2007, 12:24 PM
Rancho mase the adapter plate to mount a BW overdrive behind a D20. They made a kit for the D18 as well. Both are LONG GONE now, but you occaisionally see them at swap meets. Yes, the Saturn/Warn overdrive can be mounted into your D20 case, if you convert it to a D18. This would be an expensive way to convert to a weaker transfer case. Oh, and if you have ever owned a rig with the D18, you will know why Spicer/Dana called the D20 "the Silent transfer." They were freaking noisy.

n2ri
12-08-2007, 03:59 PM
Not Advanced adapters, and not Warns stupid planitary either.
shaft on gear type. Sierra is just a transmission shop now, the manufaturer is gone. and I get no reply from Advanced 4wd in colorado as to what ever happened to their T&H overdrive that did not require cutting drive shaft. also it was made for Toyota for 2 and 4wd use.

I want the T&H Dana 20 for my 1973 Ford Quadravan so I can get back up to 20+ MPG HWY again:D

Mitch

Herk
12-09-2007, 02:16 PM
The Warn/Saturn planetary was neither stupid nor was it weak (sorry to refute YOUR lie) It was easily stronger than the T-90 generally installed in front of it, and would last far longer than the model 18 transfer case. In a lightweight vehicle such as a Willys Wagon, Pickup or early CJ they worked wonderfully. That is why they are still being made after 40 years.

I can see no physical way to install any sort of overdive which would not require either shortening the rear driveshaft (Rancho style). Or moving the whole transfer backward, which would require modifications to both drive shafts as well as the transfer shift linkage.

I have no clue what a T&H "shaft on gear" overdrive is, but if they were worth a :o:o:o:o:o, they probably would still be around, or at least survive in some numbers. In the early 80's everybody and their dog was trying to market some miracle gas mileage cure to any burned out hippie too dumb to trade his van in on a Honda. Most of this stuff was crap and went away quickly. The little cyclone generators on top of the carb, and fuel line catalysts come to mind, although idiots still buy them for some reason.

Now, I have 2 suggestions for you if you want to modify a Ford van. First try posting to a Ford forum. I somehow doubt that there are a lot of van forums out there, but the early Bronco guys have a pretty strong community. Second, if you wish to get you Van back to 20 MPG, reverse whatever mod you did to screw up your mileage, or consider a more modern and efficient engine/transmission.

n2ri
12-09-2007, 09:24 PM
The Warn/Saturn planetary was neither stupid nor was it weak (sorry to refute YOUR lie) It was easily stronger than the T-90 generally installed in front of it, and would last far longer than the model 18 transfer case. In a lightweight vehicle such as a Willys Wagon, Pickup or early CJ they worked wonderfully. That is why they are still being made after 40 years.

I can see no physical way to install any sort of overdive which would not require either shortening the rear driveshaft (Rancho style). Or moving the whole transfer backward, which would require modifications to both drive shafts as well as the transfer shift linkage.

I have no clue what a T&H "shaft on gear" overdrive is, but if they were worth a :o:o:o:o:o, they probably would still be around, or at least survive in some numbers. In the early 80's everybody and their dog was trying to market some miracle gas mileage cure to any burned out hippie too dumb to trade his van in on a Honda. Most of this stuff was crap and went away quickly. The little cyclone generators on top of the carb, and fuel line catalysts come to mind, although idiots still buy them for some reason.

Now, I have 2 suggestions for you if you want to modify a Ford van. First try posting to a Ford forum. I somehow doubt that there are a lot of van forums out there, but the early Bronco guys have a pretty strong community. Second, if you wish to get you Van back to 20 MPG, reverse whatever mod you did to screw up your mileage, or consider a more modern and efficient engine/transmission.




looks like you broke rule #2 dont tel everything you dont know.

the planitary type OD is just like you said for light under half ton duty.
my van is 1 ton and the OD would look like a pretzel under the duty It can do.

that is the difference between gear on shaft and planitary.
as for you other comments looks like you have some unfinished homework on those subjects:banghead:

as for my milage that was before 4x4 and 4:10 gears neither of which I done nor will be undone.

Mitch:drivin:

see you on the other end of my winch cable:thumbsup:

Tom Roberts
12-09-2007, 10:05 PM
Contact Herm the overdrive guy and check out his site at Hermtheoverdriveguy.com

He will set you straight.

With one of his or Novack's main shafts a Dana 20 case with Dana 18 internal gears and the Saturn overdrive will get the job done. Could likely do the same with a well rebuilt Dana 18 with upgraded main shaft.

You will get overdrive without having to change your drive shafts, transmission mounts or motor mounts.

Check out Novack's site as to the strength of the Dana 18 and how it is a great swap for the Quadradrac too.

Some synthetic gear oil will quiet the Dana 18 considerably.

The rear output will now be on the passenger side. This can matter or not. Makes no differenc to the center pumpkin 12 bolt I have in the back of my 53 Willys Pickup. If you have a shorter rear drive shaft or enoght lift to cause a problem then you will need to switch to a passenger side drop like the Dana 44 that was in the rear of my 78 Cherokee.

Your other option would be swaping in an overdrive transmission.

Herk
12-10-2007, 12:27 AM
Gee you're right. What was Willy"s thinking when they rated their little pickup as a 1 ton with such a non-Ford-worthy transmission and transfer. I've only been working on Willys Jeeps for 25 years and dealing with this new fangled FSJ crap for 15 of those. More homework on my part is obviously in order , especially if you take the last post to be the sum total of all I know on this subject. What do you want to be told?

Herm has made a business out of the Warn/Saturn unit, as well as other parts for us flat fender minded guys. By all means contact him, he will tell you whaT will or won't work for you.

While I have a minor doubt that a 1-ton 1973 Ford van can get 20 MPG, I'm pretty darn sure that with 4.10 gears and a live front axle, you're kidding yourself.