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Atlas TC vs Dana 20 with HD shaft

nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
9,384
Loc.
PNW
Exactly garberz...My first ever Moab trip I twisted the low range teeth off on a now closed waterfall on Poisen Spider...2 hours after we set up camp!!! We had another tcase in camp and I spent a day rebuilding it...NOT what I wanted to do after driving a thousand miles one way... at that time it also took my 4 years to save 5 days vacation time...seriously, that long.

Do it right the 1st time.

Good luck...
 

markw

Contributor
Bronco Guru
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Sep 10, 2009
Messages
2,053
Yes, that application is far different than desert racing in 2 or 4 hi.
 

Action

Sr. Member
Joined
Oct 15, 2004
Messages
579
What about a transmission mount for an atlas......does anyone make 1 or just build it yourself ?
Thanks
 

bamabaja

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Sr. Member
Joined
Mar 25, 2012
Messages
729
Loc.
The Shoals
Okorangebrnco, I’m building a rig similar to yours, except 4:88s and C4, and plan similar use. What Atlas would u recommend? Thanks
 

Yeller

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Mar 27, 2012
Messages
6,781
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Rogers County Oklahoma
Okorangebrnco, I’m building a rig similar to yours, except 4:88s and C4, and plan similar use. What Atlas would u recommend? Thanks

I know you asked Okorangebrnco, so I may owe him a steak or something... but if it were me I'd do a 3.8, low enough to very controlled yet high enough to not make you hate life on an easier trail. I know how often Okorangebrnco runs 5th on the trails.

with 4.88's your gearing will match mine in 1st gear, and I tend to run with a tough crowd that wants to do the dumbest stuff on the planet.
 

bigmuddy

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Bronco Guru
Joined
Dec 28, 2004
Messages
7,330
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Marthasville Missouri
What about a transmission mount for an atlas......does anyone make 1 or just build it yourself ?
Thanks

I am installing an atlas II behind a ZF tranny and I think I will utilize a BC broncos crossmember from the ZF and move it back to the rear yoke of the Atlas using kind of a ring style retainer welded to the BC crossmember.

But I am a bit nervous to not have a crossmember under the ZF. Hell maybe I need 2 crossmembers, because it also concerns me having the atlas hanging off the aluminum housing of the ZF...%)
 

Montoya

Sr. Member
Joined
Feb 22, 2007
Messages
518
I tend to run with a tough crowd that wants to do the dumbest stuff on the planet.

I'm reminded of my dumb friend's quote "If they didn't want you to push the loud pedal up to 11 they shouldn't have made it so much fun to do it in the first place." that was usually followed by a "now hold my beer and watch this".
 

Montoya

Sr. Member
Joined
Feb 22, 2007
Messages
518
I removed my Atlas and run a 205 behind my Klune 2.7:1 doubler now.

I use the throttle a lot on sand and snow but there's absolutely no comparison between torque load on sand compared to Moab slickrock. :)

Not to Hijack, but how do you like this setup? I haven't purchased my magnum box yet but this is the route I'm taking because I have a built 205 already.

I went through three D20's before I finally went with NP so I'm definitely in the don't bother with an D20 camp, at least if you plan on making power and using large tires.

Like you said, in the sand it's hard to beat a simple NP205. Going slow on rocks on the other hand...not so much hence why I want the doubler.
 

Montoya

Sr. Member
Joined
Feb 22, 2007
Messages
518
I am installing an atlas II behind a ZF tranny and I think I will utilize a BC broncos crossmember from the ZF and move it back to the rear yoke of the Atlas using kind of a ring style retainer welded to the BC crossmember.

But I am a bit nervous to not have a crossmember under the ZF. Hell maybe I need 2 crossmembers, because it also concerns me having the atlas hanging off the aluminum housing of the ZF...%)

I would run two, especially if you plan on wheeling it hard. The case of the ZF is the weak link on it in the first place so you should try to avoid stressing it more.
 

Yeller

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Mar 27, 2012
Messages
6,781
Loc.
Rogers County Oklahoma
I am installing an atlas II behind a ZF tranny and I think I will utilize a BC broncos crossmember from the ZF and move it back to the rear yoke of the Atlas using kind of a ring style retainer welded to the BC crossmember.

But I am a bit nervous to not have a crossmember under the ZF. Hell maybe I need 2 crossmembers, because it also concerns me having the atlas hanging off the aluminum housing of the ZF...%)

Many will tell you more crossmembers and more mounts. Keep it simple, run a single crossmember on the mount made for the zf. Use the best motor mounts money can buy and let it be. Chassis’s flex, over mounting breaks everything imaginable. Those that truely go hard and don’t break almost all have simple mounts. I build stuff that gets beat in an unimaginable fashion all of them with overly rigid mounting systems are all able to flex now and parts breakage stopped.

That zf is stronger than you think let things breath and move a small amount, it will live a long happy life
 

bigmuddy

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Dec 28, 2004
Messages
7,330
Loc.
Marthasville Missouri
Yeller, thanks for the input! I recently pulled the S542 ZF to install a newer and supposedly stouter S547 ZF which gives me a slight safety factor on the case?

Saves me a bit of time too.
 

okorangebrnco

Bronco Guru
Joined
Nov 25, 2004
Messages
1,661
I know you asked Okorangebrnco, so I may owe him a steak or something... but if it were me I'd do a 3.8, low enough to very controlled yet high enough to not make you hate life on an easier trail. I know how often Okorangebrnco runs 5th on the trails.

with 4.88's your gearing will match mine in 1st gear, and I tend to run with a tough crowd that wants to do the dumbest stuff on the planet.

With the NV4500 and 5.0 the gear selection is all over the place. 1st gear is useless except for loading on the trailer or letting my 10 year old son drive. Yeller mentions me using 5th quite a lot, yes! A lot when going between trails. If I had to do over, Id go with the 3.0 or if I had a C4 again, the 3.8 or 4.3 depending on differential gears.
 

Digger556

Sr. Member
Joined
Aug 8, 2013
Messages
797
Many will tell you more crossmembers and more mounts. Keep it simple, run a single crossmember on the mount made for the zf. Use the best motor mounts money can buy and let it be. Chassis’s flex, over mounting breaks everything imaginable. Those that truely go hard and don’t break almost all have simple mounts. I build stuff that gets beat in an unimaginable fashion all of them with overly rigid mounting systems are all able to flex now and parts breakage stopped.

That zf is stronger than you think let things breath and move a small amount, it will live a long happy life

I came to post exactly this. The Atlas is heavy, but not that heavy. The ZF case is plenty strong and I run the standard mounting arrangement with no worries. Over constraining a component is a great way to break stuff fast.

My Atlas is a little older (6:1!) and it hung off the back of a M5OD-R1 in a Ranger pickup for 100,000 miles with lots of wheeling time and had no issues. The much larger ZF will be fine.
 

JB Fab

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Bronco Guru
Joined
Mar 21, 2004
Messages
1,313
Many will tell you more crossmembers and more mounts. Keep it simple, run a single crossmember on the mount made for the zf. Use the best motor mounts money can buy and let it be. Chassis’s flex, over mounting breaks everything imaginable. Those that truely go hard and don’t break almost all have simple mounts. I build stuff that gets beat in an unimaginable fashion all of them with overly rigid mounting systems are all able to flex now and parts breakage stopped.

That zf is stronger than you think let things breath and move a small amount, it will live a long happy life

Well said Yeller
 

Yeller

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Bronco Guru
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Mar 27, 2012
Messages
6,781
Loc.
Rogers County Oklahoma
The reason guys started over mounting drivetrain in my experience is due to other issues and used that as the “fix”. Usually it is over poor factory motor mounts that are overly soft and easily broken. Or driveshafts are too long and push on the outputs enough to break the transmission or bell housing. My favorite is their drag race buddy convinced them to use a mid plate and solid mount everything, then the carnage gets real impressive (happens in drag cars too for the same reasons).

Funny story I’ll share. I have a really good friend that is an engineer that I’ve helped for years. He insisted on using a mid plate in a tube chassis butgy, shared my experiences, used the mid plate. In 4 trips with under 2 hours total drive time and 4 broken transmission cases the mid plate got cut and installed some bushings, 12 years later no broken transmission cases. Now ripping the guts out from 6000rpm neutral drops is a different story...
 

Montoya

Sr. Member
Joined
Feb 22, 2007
Messages
518
Montoya...Have you looked into the Titan box from NWFab in BC? Very short, extremely strong, light weight...essentially a modern day KluneV like I run.

It would be really hard for me to go back to wheeling w/o a doubler... I do all types of terrain so the gear choice is important.

NWFab--
http://www.northwestfab.com/Titan-Series-NP205-BlackBox-i_p_2402.html

That's a great option, didn't realize it is actually a little shorter. It's definitely in my list now.
 
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