I have a 1999 ram van 3500 extended or full-size with a busted differential and am in the market for a working rear axle. My question is if the rear axle on an extended van is a different size than the regular dodge ram van.

 

Not ordinarily -- check the sticker on the underside of the hood to see what you have.

 

do you mean that the sticker says what size the axle is? and in that case i don't have a non-extended van to compare it to. i'm just wondering if i can take an axle off of a non-extended van and put it on my extended van.

 

I did. No problem. I have a Chrysler 9.25, 12 bolt, with 3.21 gears, on a '94 b250 extended body. Donor rear end was a standard '95 B250.

 

Sorry, I may have provided incorrect info.
In browsing the below site, I think there could be a difference, depending on whether or not you have the 5500 or the 6200 lb. Dana 60 axle, but it doesn't exactly specify whether standard or extended. If you have the Chrysler 9.25, there apparently is no difference. If the label under the hood doesn't tell you that, then it may be on the sticker on the door post.

Go to www.car-part.com and see what your options are.

 

You likely have the 9.25 but the full floating Dana axle is a possibility as well. These Danas have thicker hubs sticking well out from the rims.

I am pretty sure you need an Axle from a Van and not a truck as the axle tubes and spring perches are not the same between trucks and vans.

The 9.25 is prone to pinion bearing issues. If you get a junkyard axle consider installing all new bearings before installing it.

When my 8 3/8 was done for, I got a 9.25 from the junk yard, installed it, and found it louder than the 8 3/8 that had badly worn ring and pinion and heavily pitted spider gears. At that point I kind of threw up my hands and had a professional driveline shop rebuild it and it was not cheap. 500 for the junkyard axle, ~800 for the rebuild. They did straighten the housing and repainted it along with installing all new bearings, but the R&P and the Spiders and the axleshafts were reused.

That was the last time I paid someone else to work on my Van, and that was 6.5 years ago.