[chris demartini]

A few months ago my Atlas broke off the back of my 700R4, for the 3rd time, and I just got it back together last week (trans shop drama, dont ask).

Today I woke up when it was still dark and hauled 150 miles out to Paragon. I got to wheel for all of 15 minutes before hearing a few quarts of ATF hit the ground..... again :mad3:

The bolts actually pulled out of the housing, not loosened out. The threads were full of aluminum.

SBC with Advance weld-on motor mounts
700R4 junkyard edition
Atlas II 3.8
Energy Susp. mount

The trans mounts to my belly pan. It is 3/8" thick, braced and supported at both ends (it does not move). I was crawling around in 1st, never got on the gas at all.

Why does this keep happening and what do I have to do in order to actually be able to drive this thing?

 

[Grendel]

Do you have a mount on the back end of the Atlas?

It's alot of weight/torque to hang...

Do your engine mounts match the transmission mount's material and orientation?

From my experience, you want the transmission to be able to move slightly more than your motor.

Not an Atlas, but a great transfer case mount:

 

[chris demartini]

No mount on the back, where did you get that one for your stak?

From what I can see the AA motor mount bushings are the same material as the Energy Suspension trans mount. The trans mount is a factory style that bolts to the Atlas adapter and the crossmember, or in my case the bellypan. Should I switch back to a factory rubber t-case mount?

Only way to isolate the t-case at the frame like yours would be to run the exhaust through the firewall between my legs and along the bottom of my nutsack. There is about 1/2" of clearance around the exhaust at any given spot.

Here is an older picture from when I first finished the Jeep.

 

[Grendel]

No mount on the back, where did you get that one for your stak?

From what I can see the AA motor mount bushings are the same material as the Energy Suspension trans mount. The trans mount is a factory style that bolts to the Atlas adapter and the crossmember, or in my case the bellypan.

Only way to isolate the t-case at the frame like yours would be to run the exhaust through the firewall between my legs and along the bottom of my nutsack. There is about 1/2" of clearance around the exhaust at any given spot.

Here is an older picture from when I first finished the Jeep.

It's not mine. I want one like it. Hell, I can't move anything down the passenger frame rail anyway. So I am running the passenger side exhaust forward and around the oil pan.

Stak does make a mount that I have... it's on one side. Fab on the board made that one for his. Here's his build thread:
http://www.pirate4x4.com/forum/showthread.php?t=529060

Could you grab the back of the transfer case from the top?

Is it possible that your belly pan is deflecting? I'd add some bracing to that.

 

[chris demartini]

It's not mine. I want one like it. Hell, I can't move anything down the passenger frame rail anyway. So I am running the passenger side exhaust forward and around the oil pan.

Stak does make a mount that I have... it's on one side. Fab on the board made that one for his. Here's his build thread:
http://www.pirate4x4.com/forum/showthread.php?t=529060

Could you grab the back of the transfer case from the top?

Is it possible that your belly pan is deflecting? I'd add some bracing to that.

The atlas is harder to mount from the top than a Stak is from what I can see. It might be possible, I'll look at it tomorow (jeep is in storage over the winter)

The belly pan is not deflecting. It's bolted to a 2x2x.25 lower link crossmember in the back and has an upside-down peice of .25 angle iron welded across the top in front. We suspected my last skid of causing this problem so I made the new one out of 3/8, tied it to the link x-member and braced it. I lifted the Jeep by the skid and it did not deflect.

 

[coolcruiserfj40]

dunno how it works yet but heres what we did with my buggy

 

[Grendel]

The atlas is harder to mount from the top than a Stak is from what I can see. It might be possible, I'll look at it tomorow (jeep is in storage over the winter)

The belly pan is not deflecting. It's bolted to a 2x2x.25 lower link crossmember in the back and has an upside-down peice of .25 angle iron welded across the top in front. We suspected my last skid of causing this problem so I made the new one out of 3/8, tied it to the link x-member and braced it. I lifted the Jeep by the skid and it did not deflect.

Sounds solid then.

Quite frankly, that's the first thing I would chase: Getting that back end mounted down some how, even if only one side of the frame. Most of the factory configs that take serious abuse I've seen have some sort of rear t-case mount. Most everything with a 205, etc.

 

[chris demartini]

Interesting. Just run a long bolt through it? Can that be built to the same height as the AA adapter?

 

[Grendel]

Interesting. Just run a long bolt through it? Can that be built to the same height as the AA adapter?

This is what I have welded to the passenger frame rail:

 

[chris demartini]

Sounds solid then.

Quite frankly, that's the first thing I would chase: Getting that back end mounted down some how, even if only one side of the frame. Most of the factory configs that take serious abuse I've seen have some sort of rear t-case mount. Most everything with a 205, etc.

What if I made a short "crossmember" that bolted to the adapter solidly and my bellypan with body mounts, but wasn't too wide that it interfered with the exhaust?

Only other solution I have room for is this.

(not mine)

I gotta run, I'll be back around 3 am EST. If anyone has any ideas I'd like to see them.

 

[chris demartini]

This is what I have welded to the passenger frame rail:

Got any pictures? Availible for an Atlas?

 

[JabNasty]

I solid mount everything motor mounts, midplate which helps alot, trans and transfer thats 4 mounts which makes it very rigid. Before when everything was rubber mounted I had a problem of breaking transmissions and pulling them off the back of the trans just like what your saying.

 

[Grendel]

Got any pictures? Availible for an Atlas?

There's pictures of the mounted t-case in my build thread. No idea if it's available for an Atlas.

I know there's a vendor here that does one though:

http://www.pirate4x4.com/forum/showthread.php?t=436473

The picture you posted is still grabbing the front of the t-case. Still would have HUGE weight on the back end. Notice what others posted in that thread I linked? Not an uncommon problem, from what I can tell.

 

[Fl-Krawler]

i am having the same exact problem on my 4l60e/atlas on my buggy and i am using the same bushing mounts for both the engine and the tranny.the first time it happened i thought the supplied AA bolts were too short, so i got longer ones, the secont time it pulled it managed to break the top half of the tranny, so i drilled and tapped the bolt holes to 1/2" thinking that will help.. just discovered it leaking yesterday so it looks like i get to pull it apart AGAIN..this time i am gonna build a support bracket tha supports both the atlas and the tranny.i'll post some pics up when i get it finished and let you know how it works

 

[X-Rated]

jesus, how many people running atlas Tcases end up breaking their transmissions?

 

[DOUG38S]

Done it.
Somehow you need to support the Atlas a little more.
Either get a Roark Fab unit or one that AA has.
I mounted my Atlas from the top supporting the unit at the adapter with the AA unit and may possibly in the offseason get a Roark fab unit as well for the rear output.

 

[mark.bales]

mine pulled apart once like 6 years ago but nothing since then.(i have not wheeled my own rig for 3 years this summer:mad3: :shaking: )

it was on my 85 XJ with a 4.3 Chevy, 4.3 atlas and 700r4.
it striped the threads out of the 700r4

 

[Butler]

I had looked into an atlas mount a few years ago and everybody told me it was a bad idea, I don't know why. I run a c-6 and the bolts go all the way through the adapter and case. Having said that, I am doing a bunch of repairs this winter and some sort of brace is on the list. I am going to make a plate that uses some of the allen bolts on the bottom cover plate and ties into another crossmember. I am worried about the same problem you are having except if it happens to me I'm sure it will take the back of the trans with it.

 

[BnTMike]

running the same combo... 700r atlas.. I have a lazer cut mount I bolt to the front of the front output.. similar to above.. my drive train doenst move...

PS sure you got the right bolts into the 700r4. I cant say for sure but I think they are metric in some case's. wrong bolts would pull threads ...

Mike-

 

[chris demartini]

Mike, you are correct. The bolts are metric. I'm using the allen cap head screws that came with the Atlas. Do you have any pictures of your support?

I don't think I can use that Roark support on the rear, but I may be able to cut it down for the front. Would it still support the case enough mounted at the front?

Also, if I shorten my output shaft and remove the 1" spacer from the adapter, will that help at all? My trans is apart right now and it would be very easy to do.