Atlas transfer case or mating a sport transfer case to the 392

Red392 · 2026-10-12T19:41:53-0600

Anyone here with an Atlas transfer case? What gear ratio did you use? 3.0 or 3.8 or? Why did you chose that ratio?

Has anyone mated a sport box to the 392 box to get selectable 2 wheel drive? Does that mod still use the clutches in 4wd?

Thank you.

gr1p · 2026-10-12T20:11:45-0600

Yeah bud, Atlas swap on mine 3:1 ratio. Awesome

It makes a lot more noise than the stock chain drives so dont be alarmed

Red392 · 2026-10-12T20:25:14-0600

Thank you! Why 3.0?

EBYCREEK · 2026-10-12T21:35:48-0600

I did the 3:8.1 ratio because I’m still running the 3:73 gears on 37 inch tires. I’ve had mine installed for 2 years. Also add the FAD motor to the front axle. I haven’t noticed any transfer case noise going down the highway.

Donut · 2026-10-13T05:29:13-0600

Red392 said:
Anyone here with an Atlas transfer case? What gear ratio did you use? 3.0 or 3.8 or? Why did you chose that ratio?

Has anyone mated a sport box to the 392 box to get selectable 2 wheel drive? Does that mod still use the clutches in 4wd?

Thank you.

The Sport’s Command-Trac (part-time) case is a mechanical unit. It uses a shift collar to fully engage or fully disengage the front driveshaft — no multi-plate clutch pack like the 392’s Selec-Trac MP3022. That’s why the Sport case is used in the common swap to eliminate the clutches and get true selectable 2WD + locked 4WD.” I've been running a sport t case in my 392 swapped jk ever ( its the stock unit 350K miles , 100K behind the 8HP70 and 392) its been great. i've done a few 4x4 street launches and been wheeling a bunch , no issues ... I would still like an atlas to font dig and have 2wd low range . i would go with the 3.1 to keep the ratio close to stock , it works well with the power of the 392.