Rear Driveshaft size question.

[Audiowriter]

I have a 2012 Ram 3500 4WD Crew Cab ST DUALLY (DRW).
I bought it used with 140,000 miles.
However, after spending almost 3 days trying to match up the 3 REAR MAIN driveshaft U-Joints for a DUALLY (DRW)-
Come to find out my driveshaft calls for SINGLE Rear Wheel U-Joints (SRW)

Is this normal or did someone put a different driveshaft in my truck at some point?

(I rebuilt both front and rear driveshafts using my home made horizontal hydraulic press =
A 1.5 ton bottle jack and a piece of a 20 inch wide "I" Beam.)

(Had to use a grinder to cut out part of the old Rear shaft joints...)

 

[Ozymandias]

I never heard about a difference between SRW or DRW - but they had differences between Stick shift or Auto Trans.

And in general there were many changes through the years if it comes to driveshafts and sizes of u-joints. To me it almost looks like they put on what ever they had in stock at the factory.

 

[Audiowriter]

The DRW u- joints have quite larger center "X" that wont fit into the SRW yoke.
I believe the caps are the same diameter - but might not be the same length???

 

[crazy jerry]

the best thing to do is call or stop by a dealer with your vin. that style of truck may have been fitted with two or three different ujoint and driveline combinations depending on what engine and transmission were originally installed in it.
also be aware that some of them dodges (not sure of your exact year) used aam specific ujoints (1555, 1485 etc). theyre close but not the same as spicer 1550 and 1480. many people have made the mistake of thinking theyre the same. again this is why its important to go based on vin

 

[Audiowriter]

I got them all done.
2 Moog's and 1 Spicer in the front axle (forget the numbers...)
The rear took 3 Spicer's 5-3206X

 

[crazy jerry]

its common for manufacturers to use numerous ujoint and driveline combinations. ford has probly three or four combos as well. my truck is '17 2500 6.4 4door shortbed 4x4 with one piece aluminum shaft and 1555 aam specific joints on the rear. not sure what the fronts are. probly aam 1415 i suppose

 

[Ozymandias]

its common for manufacturers to use numerous ujoint and driveline combinations. ford has probly three or four combos as well. my truck is '17 2500 6.4 4door shortbed 4x4 with one piece aluminum shaft and 1555 aam specific joints on the rear. not sure what the fronts are. probly aam 1415 i suppose

Yes 1415 was the last revision with u-joints before they went to a CV-driveshaft.