whats the difference of either getting the extensions or justing getting a more heavy duty driveshaft

 

Well, using an extension causes your DS to be shorter so, worst U-joint angle. Other than this I cannot see another.

David

 

If your only issue is lack of length (i.e the overall shaft is too short), then an extension is an inexpensive way to extend a shaft:
- http://www.4crawler.com/4x4/ForSale/...ftSpacer.shtml



If the problem is that the slip yoke is not long enough (that is it can compress fully yet extends too far and separates), then the extension will not help, a longer slip yoke will be needed.

As noted, the angle on the driveshaft will be slightly higher with the extension, but not by much. For example on a ~24" long front shaft at a 20 degree angle, a 1" extension would add perhaps 0.8 degrees to the angle. The angle change will depend on the length and angle of the shaft and length of spacer used.