There is a clanging noise when i put it in gear and can hear it while driving is it the rear end or universal joint

Lift the rear end of the Explorer with a floor jack. Place jack stands underneath the rear axle, by the leaf spring perches and lower the Explorer onto the stands. Pull the floor jack out of the way. mark both ends of the shaft for reinstalation.

Crawl under the rear end and unbolt the universal joint retaining straps from the rear differential yoke.

Pull the drive shaft and universal joint away from the rear differential yoke by hand.

Remove the retaining rings that hold the universal joint into the drive shaft with needle-nose pliers.

Support the end of the drive shaft on a jack stand and place the socket extension against the universal joint cap in the drive shaft yoke. Tap the socket extension with the dead blow hammer until the universal joint cap comes out of the yoke.

Clean the sockets in the drive shaft yoke with the tip of a pocket screwdriver to remove any built up road dirt or other gunk.

Remove two of the caps from the opposite ends of the replacement universal joint. Be careful to keep the bearings in the caps.

Position the replacement universal joint in the drive shaft yoke and put the cap on the outside. Use the socket extension and dead blow hammer to tap the cap through the yoke far enough to expose the retaining ring groove. Put the retaining ring on that side with the needle-nose pliers. Repeat this for the other cap.

Move the drive shaft back up to the differential yoke, line up the new universal joint with the differential yoke and reinstall the universal joint retaining straps with the wrench. Lower the rear end off the jack stands with the floor jack.