I have a 2000, 3.9L, 2 wheel drive sport with 3.55 gears. I have noticed a couple of complete posi axles on craigslist from durango's close to the same year with 3.55 gears. Does anybody know, would this be a direct fit or should I look for a Dakota rearend. Do all Durango's come with 16 inch wheels since my truck has 15 in rims.

 

as for wheel size, it depends on the year of the durango/dakota. 97-99 where 15" and 00-04 came with 16" ( i think). and the r/t had the 17". how ever, it really doesn't matter since the bolt pattern is the same.

you will have the do some cut and welding the the axle for it to fit the dakota tho.

 

And 15" wheels won't fit an axle that came with 16's due to the bigger brakes. Durango axles have the spring perch on the opposite side (flipped) and 1\4" further apart

 

Why do you want posi?

 

If all you want is a posi, buy just a posi differential carrier (new or used) and install it in the housing you have now. You'll save yourself a bunch of work.

 

Well we all look at ads for used parts and deals, came across the axles and starting thinking maybe... I down graded from a 96 Jeep Cherokee after the frame rotted and the spring shackles came up throught the back seat area. Needed a vehicle and this Dakota Sport had only 89,000 and paid $1800, of course I get the P1740 transmission code, but runs and shifts ok. Living in upstate NY, the snow can get fairly deep and when I go Hunting the roads can be tough to run in 2WD. I have seen a complete axle with 3.55 gears, brakes and 15 in wheels and figure it may be easier to swap the axle than drop in a posi unit. Figured a posi unit and a set of studded snow tires would make this truck dig through snow and mud like my old Cherokee. May need to look specifically for a Dakota rearend if I will have to cut and weld the Durango axle.

 

If you were talking about changing the ring and pinion gears, I would agree that it's easier to swap out the whole axle. But replacing the carrier is easy and doesn't require more than a few special tools (torque wrench, dial indicator, and side adjuster socket). If you replace the carrier bearings (as you should), you don't even need a puller, just something to drive the new bearings on.

Posi clutches are a wear item and they're not cheap. This is one of those situations where you may come out ahead in the long run if you buy new.