Topic: Tera 4:1 or SM420

[neale_rs]

5 and 6 are a 5:1 and a 4:1, respectively. 

If anybody else wants one I have the spreadsheet ready to go.

[Jeffy]

The four speed would be about $600 more for my application (the prices depend on several options).  Depending on the gearing option (10.34 low or 5.44), the crawl ratio would be either 185:1 or 97:1.  One thing to consider is the driveshaft work that might be required.  The 2sp Atlas would require a lengthening the rear DS several inches but the 4sp, depending on the rear output option, could end up either 1 inch shorter or 1 inch longer than what is in the Jeep now.  It might be possible to select one or the other and avoid a DS modification, making the actual cost difference a bit less.  Lots of variables to consider...

Actually, even with a 2-speed Atlas, you're not assured that the driveshafts will still work either.

[neale_rs]

With the 2 speed they would definitely not work.  With the 4sp there is a chance but I would have to check the current spline engagement.  It sort of looks like it is more in than out so I would go for the short output option and hope for the best. If DS work is needed, it would just have to get done, even if I wouldn't be able to pay the mortgage that month!