About 4 years, 20,000 miles. Big joint, I thought it would out last the truck. I'm waiting for Jeff's to open to get them on the blower. Brian
Measuring Spicer Universal Joints
The "series" of a driveshaft or universal joint is determined by the actual dimensions of the u-joint. While the front and rear u-joint can be of two different sizes the shaft is only as strong as the smaller one. The 1310 series u-joint measures approximately 3 1/4 inches wide. The 1330 and 1350 both measure approximately 3 5/8 wide. The 1310 and 1330 series can have cap diameters of 1 1/16 and/or 1 1/8 inch or a combination of both sizes. The 1350 series has a cap diameter of 1 3/16 inch and the body and journals are bigger than the 1310 or 1330. Remember 1350 is almost never found in production car driveshafts.
All Spicer type joints used on Ford 4x4 trucks use external snap rings. To determine the series of a Spicer Universal Joint, measure the overall width of the assembled universal joint. This will give you the "snap ring" or "lock up" dimension. (1977 and older F-250 trucks with remote mount transfer cases used an unequal length 1310x1330 u-joint.)
Next, measure the diameter of the caps. In most cases, the cap diameters will all be the same, however, 1330SP (1330F) joints with 2 different cap sizes are common in most Ford full size CV and standard shaft applications from 1979-on. 1330SP joints are never found in the CV joint itself, but they are used in the slip yokes of many CV shafts. The larger diameter caps always fit the axle or pinion yoke. It is not uncommon to find a straight 1330 joint at one end of a CV or non-CV shaft and a 1330SP on the other end. Always measure your joints before ordering replacements. When in doubt, call us at: 406-446-2427.
http://quad4x4.com/Ford%20Drive%20Shaft.htm#SPLINE
