should I invest in my Dana 20 or?

[47bronco]

Hey guys, I would greatly appreciate some help here. I have been scouring the internet looking for the answer to no avail. I have a 72 Bronco. My 351w is out being rebuilt and I have a leaky Dana 20 still in the the truck. I am debating whether to take out the Dana 20, rebuild it, twin stick it, put some teralow 3:15s in it and be on my way or is my money better spent on a Dana 300 or? It has 35s and be used for conquering some local socal desert and mountain trails. Its sounds like an Atlas or Stak will be pretty expensive and require a body lift to install so I am leaning towards the Dana 20. Will this D20 be up to the task? Are they strong enough? Is the teralow and good product? If not, will the Dana 300 bolt right in? I need to pull the trigger on this and am a bit confused right now.

 

[hartbronco]

What trans are you running ? and Yes I think the Dana 20 will do you .

 

[bax]

The 20's are strong and cheap. Run one till you break it and see what you think. keep in mind you can replace them 10 times before you pay for an atlas.

 

[73azbronco]

after digging into mine from a 73 with a long term 351w in front of it, I would recommend just reseal it with new seals and such, when I opend mine my first thought was "this was a mistake" as nothing was wrong inside. I think it would have lasted another 100,000 miles above it's current 150,000.

 

[broncnaz]

Welcome
My D20 has over 300,000 on it and the only thing I've ever replaced on it is output shaft seals. I'll also ask what tranny are you running?
If your not going to hammer on the truck the D20 will be fine. If you do go with tera low gears then you should upgrade the rear output shaft as well.

 

[sketch]

Hey guys, I would greatly appreciate some help here. I have been scouring the internet looking for the answer to no avail. I have a 72 Bronco. My 351w is out being rebuilt and I have a leaky Dana 20 still in the the truck. I am debating whether to take out the Dana 20, rebuild it, twin stick it, put some teralow 3:15s in it and be on my way or is my money better spent on a Dana 300 or? It has 35s and be used for conquering some local socal desert and mountain trails. Its sounds like an Atlas or Stak will be pretty expensive and require a body lift to install so I am leaning towards the Dana 20. Will this D20 be up to the task? Are they strong enough? Is the teralow and good product? If not, will the Dana 300 bolt right in? I need to pull the trigger on this and am a bit confused right now.

I just priced the crawler transfer case gears kit from wildhorses4x4.com $ 824.99 It comes with all the gears, seals,and gasket. I was looking at the Klune-v Extreme Underdrive. It bolts up in place between the transmission and the transfer case. It multiplies your existing gear reduction by up to 4 times, rather than a usual underdrive of 1.2 times.

 

[TN1776]

The Dana 20 is by far the best fitting transfer case you can put under a Bronco. I've been running mine for 2 years of rock crawling with a mildly built 351 and 37" tires with no problems yet. I'd like to have slightly lower gears once in a while but overall its done its job respectably. I am not sure the tera-low kit is quite worth the money for the slight reduction it gets you. An Atlas or Stak is on my wish list but honestly I'm pretty happy with my D20.

 

[broncnaz]

The klune V is similar to the 203 range box conversion. Just uses a 231 range box instead the 4-1 is weaker than the 2.7-1 and you'll have to build a crossmember setup. but the price is compareable if your planning on swapping t case gears and upgrade the D20 output shaft. Although the D20 output should also be upgraded with the klune v. but you get more gearing selection with the klune V.

 

[6daze]

What trans do you have? Are you happy with it?

When I completely sheared off the output shaft of my Dana 20 (in the middle of a trail in Moab) I took the oportunity to upgrade to a 5 speed ZF trans and Atlas. The Atlas bolted right up to it, no pricy adapters.

IMHO in order to build a Dana 20 correctly, you can almost buy a Atlas/Stak.

I have a 1" body lift but it was not required for the Atlas...

 

[sprdv1]

The 20's are strong and cheap. Run one till you break it and see what you think. keep in mind you can replace them 10 times before you pay for an atlas.

X2...

Welcome to the site!

 

[gravy]

As said before, stick with the D20 until it breaks (if it does), its compact and strong. I am going with the Northwest Fab Blackbox-i for the 20 which can later be upgraded for the Atlas if I change. It is 2.72 to 1 and only 5 inches long. The WH extreme output will be necessary and I recommend it for all doing even mild wheeling. The total length with the planatery box and tcase is 2 inches longer than the Atlas alone, I need the speedo. The blackbox also allows you to clock the transdercase to you preference. Crossmembers will need to be built.

 

[mws eb]

thinking of going with the 3.15 also and found them on 4x4groupbuys for 733.00. never dealt with them but almost 100 cheaper then any other prices i've found.
is wild horses the only place to get an upgraded output shaft? thought B C carried one.

 

[70_Steve]

Hi and welcome to the site.

I'll throw my support behind the Dana 20 also. I''ve been running the TeraLow (3.15) gears for several years and for the driving I do, they've been perfect. I run an NV4500 with 35's and really enjoy the 80-1 crawl ratio while being able to cruise the Highway at 65 and only turn 2200 rpm. Yes, there have been issues with the output shaft. A friend just broke his output shaft a couple months ago, but he's also the same guy that like doing donuts in the parking lot with a spooled rear!!! Plus, these transfer cases are 40 years old. Who knows what's been done to/with them in the past.

I read the comments about how much you have to invest in a Dana20 compaired to the price of an Atlas or Stak. But I've never seen the total price for each. Wild Horses price of $830 for the TeraLow gears and $430 for the Extreme output shaft equals $1260 for an almost bulletproof transfer case with a great gear ratio. OK, then, since these transfer cases are 40 years old, maybe throw in $30 for new front output shaft bearings. (The Extreme rear OP shaft comes with bearings, and the TeraLow gear kit comes with EVERYTHING else you need to rebuild the Dana 20)

Someone please tell me how I can install an Atlas or Stak for $1200!!!

 

[6daze]

No one told you an Atlas would cost $1200.

Pay for someone to rebuild your Dana 20 ( I couldn't do it)

Twin stick it

You have a 40 year transfer case

Add the cost of adapters for many transmissions.

I broke my Dana 20 because my gearing was not low enough. The stock 3 speed was never going to get me there.

 

[gravy]

Just to add some info, the WH output with out the housing only adds 3/4 rather than the advanced adapters kit (also sold by WH) adds 1.3 and you will need to change the speedo set up also. BC was selling a 300m shaft that I think Jack OBrien was producing but you would have to call them- havent seen it on their sight in a while.

I just finished pricing a new Atlas 4.3 with HD front output, mechanical speedo and Bronco shifters for 2400 plus shipping for those that are wondering the price. You will needa cable conversion also for another 100 so by the time I would be done with all the odds and ends we are talking almost 3k for a 2 speed. It is 3 inches longer than the D20 with the mechanical speedo

For 1600 I got the Crawl box and I got 2 Dana 20's for a case of beer. Another 400 for the Extreme Output and for 2k I have a 4 speed and if I break the D20 I have spare parts and the ease of getting parts for them.

Groupby is a good place to get the TeraLow but WH will probly work out a package deal with you if you buy everything at once.

 

[70_Steve]

No one told you an Atlas would cost $1200.

Uhhh... Yes they did!!! See below

IMHO in order to build a Dana 20 correctly, you can almost buy a Atlas/Stak.

Pay for someone to rebuild your Dana 20 ( I couldn't do it)

$300

Twin stick it

$134

You have a 40 year transfer case

It doesn't hurt metal to get old.

Add the cost of adapters for many transmissions.

NO! The cost to adapt an aftermarket/non-original transmission should considered part of the cost of the transmission install!


So, if you can't rebuild the Dana 20 you would have to pay someone to install the Atlas. That along with modifying driveshafts, speedo considerations, crossmembers, etc. Having never done all that, I can only guess at a final pricetag of over $3000. I really would appreciate someone who has installed an Atlas listing the complete cost to install.

The modified Dana 20 still comes in at $1600... give or take.

 

[fungus]

Used set of Tera lows in great shape. Posted up here last night...

http://classicbroncos.com/forums/showthread.php?t=174317

Something super cheap I did to strengthen my D-20 (seen the actual cases split open) was toss the original inspection cover and build one out of 3/8" steel plate (actually it's just a piece of 3/8"x 6" flatbar). I used the old cover and a transfer punch to mark the holes, drilled'em, rounded the corners and bolted it on with some RTV and she hasn't leaked a drop in a year. I had the steel on my garage floor so that was free and 10 grade 8 bolts w/ lock washers from Lowes.

 

[47bronco]

Thanks guys. I am going to take your advice and stick with the D20. I was hoping you would recommend that! I have a C4 tranny by the way.

Can anyone recommend a good shop to rebuild the dana? I am in N. san diego.

 

[70_Steve]

Can anyone recommend a good shop to rebuild the dana? I am in N. san diego.

Do it yourself. It really is pretty easy.

Or, PM 73stallion. He may get down to SD.

 

[6daze]

Border Parts in Spring Valley. Ask for Trent.

(619)461-0171