Notorious Atlas Shifting Difficulty

[Fouledplugs]

It seems to be a common occurrence that the Atlas tranfer cases carry with them, a bit of difficulty shifting in and out of 4wd.

Even with the “HD” shift linkage that eliminates rhe plastic bushings and such, the case can still be troublesome shifting.

After doing a little bit of reading on their site, the difficulty is a result of utilizing synchronizers in the case.

From what I understand the case, be it a race case or not, has the issues. So case build has no bearing on it.

Has anyone removed or had a case built without the synchros? I know some of the Ultra4 guys are able using air shifters for their cases and I am confident that removal of the synchros would allow this mod. I am bot looking to go air shift, but would like to go without the synchros for a better shifting case.

Any opinions, experience on an Atlas case without synchros?

 

[Rescue6]

Mine has shifted great once I got the shifters adjusted properly. Took a little time fine tuning the c adjustments but the twin sticks shift really smooth now and the. 4 speed hi low shifts fine as well.

 

[Fouledplugs]

Mine has shifted great once I got the shifters adjusted properly. Took a little time fine tuning the c adjustments but the twin sticks shift really smooth now and the. 4 speed hi low shifts fine as well.

Are you using the cable shifters?

 

[astjp2]

I have the rod shifters on my atlas, it was only easy to shift when it was new for about a week. Dana 300 was the same way when I twin sticked it.

 

[Justin Homan]

Sometimes i have to have my jeep rolling a little bit to shift my Atlas but it never really requires much effort.

 

[mrblaine]

Are you using the cable shifters?

The vast majority of difficulty shifting an Atlas is due to the straight cut gears in the case and they don't like to move if there is any pressure on them at all. If you don't relieve the bind, they won't shift and there is nothing you can do to make them shift. That doesn't imply that they ever shift like a transmission does, but they only require light pressure on the shifters to move the forks around if there is no bind.

The easy way to find out is get it on an obstacle where you want to pull the rear out and when it won't move, simply reach over with your other hand and move the trans from 1st to reverse with light pressure on the shifter handle. You'll feel the bind go away and the shifter will move very easily.

 

[Fouledplugs]

Sometimes i have to have my jeep rolling a little bit to shift my Atlas but it never really requires much effort.

Atlas has an article that covers that. Because of the gear design, it comes down to proper gear alignment in order to shift.

 

[mrblaine]

Atlas has an article that covers that. Because of the gear design, it comes down to proper gear alignment in order to shift.

Just be glad it isn't the opposite issue like Stak had. The angle on the teeth was not engineered right and you couldn't keep them engaged.

 

[Daryl]

The vast majority of difficulty shifting an Atlas is due to the straight cut gears in the case and they don't like to move if there is any pressure on them at all. If you don't relieve the bind, they won't shift and there is nothing you can do to make them shift. That doesn't imply that they ever shift like a transmission does, but they only require light pressure on the shifters to move the forks around if there is no bind.

The easy way to find out is get it on an obstacle where you want to pull the rear out and when it won't move, simply reach over with your other hand and move the trans from 1st to reverse with light pressure on the shifter handle. You'll feel the bind go away and the shifter will move very easily.

Are they straight cut or low helix? I took this picture at Advanced Adapters booth during KOH 2020.

 

[mrblaine]

Are they straight cut or low helix? I took this picture at Advanced Adapters booth during KOH 2020.
View attachment 142155View attachment 142156

There was a big discussion in a Stak thread and one of the issues was the staying engaged issue. Someone apparently reported the Atlas having straight cut gears erroneously since it is very easy to see they aren't.

 

[Rescue6]

Are you using the cable shifters?

I’m using the standard rods for the twin sticks and a cable for the hi low of the four speed

 

[Fouledplugs]

There was a big discussion in a Stak thread and one of the issues was the staying engaged issue. Someone apparently reported the Atlas having straight cut gears erroneously since it is very easy to see they aren't.

Am I reading post # 6 correct? And then also reading post #10 correct? In 6 you mention that they are straight cut. Then in post 10 you mention that they are not straight cut. I’m sorry but I am confused.

 

[mrblaine]

Am I reading post # 6 correct? And then also reading post #10 correct? In 6 you mention that they are straight cut. Then in post 10 you mention that they are not straight cut. I’m sorry but I am confused.

I was told they were straight cut in a Stak discussion as to why the Stak kicked out of gear and the Atlas didn't. The info given to me was apparently erroneous as evidenced by the pictures.

 

[Wildman]

I MIGHT be one of the lucky ones since case #3 doesn't seem to have that issue BUT who knows since I don't have a lot of miles on it. I blew up two STaK's cases by flat towing my Jeep. After the second case I was told I had to stop flat towing the Jeep even it was them that had told me I could flat tow it and how to shift the t-case.
Just like the Atlas if I am trying to shift the rear out when it's under a bind it is next to impossible to get it to shift. I don't seem to have as many issues shifting it in and out of 4WD either in the lo or lo lo.

I bent the shift rods with their original shifters so they sent me new shifter rods and a redesigned shifter.

 

[Fouledplugs]

I was told they were straight cut in a Stak discussion as to why the Stak kicked out of gear and the Atlas didn't. The info given to me was apparently erroneous as evidenced by the pictures.

Makes sense.

 

[auttiman]

My Scrambler has an Atlas. It was installed around ‘00. I shift my transmission into neutral while barely rolling then shift my twinsticks easily. OP must be trying to shift while in park.

 

[Fouledplugs]

My Scrambler has an Atlas. It was installed around ‘00. I shift my transmission into neutral while barely rolling then shift my twinsticks easily. OP must be trying to shift while in park.

Nope. Just think that without synchros it may shift even easier.