Broken U-joint flange

I have had a little bit of vibration since I bought the truck a couple years ago, but after lowering it recently I noticed it had gotten a little worse. Well, today the flange that attached the rear U-joint to the pinion flange broke at 65mph on the freeway. Yesterday I noticed a metallic sound coming from the rear of the truck under hard acceleration when turning right. Guess I should have gotten under there a little sooner.

I am not sure if I had a failure of the U-joint (caps or needle bearings?) or if it was because of the driveline geometry. I lowered the front of the truck with 3" beams and the rear with 4" leafs, but I had to raise it back up with 2" shackles. I am not running a spacer under the center support bearing.

I took some measurements today. The center of the pinion flange is 13" from the ground. The center of the U-joint flange at the center support bearing is 12.5". The Center of the transmission output shaft is at 13.5". I also measured the angle of the pinion flange with relation to the ground. I got a reading of 83 degrees, so I imagine that means it is 6 degrees up since the pinion is pointing up.

Should the pinion be pointing down a couple degrees? Do I need to move the center support bearing up 1/2" or 1"? Where would I get such a spacer to move the center support bearing up?

I also want to take this time to replace the center support bearing. Is there a how-to anywhere on the internet? Would a driveshaft shop be able to replace it?

I obviously need a new flange for the rear U-joint. Is this a 7.5" Ranger specific piece, or can I get it from any 7.5" equipped Ford car or truck? Does the driveshaft still appear to be useable?

Looks like the cap of the u-joint had been spinning inside the ear of the yoke. The driveshaft, while it would probably still be fine, looks like it needs to be replaced or had a new end put on it.

your carrier bearing location sounds acceptable to me. unless there is a spacer under it already that can be removed, there is no way to move it up. you do need to get your pinion anxle fixed, however. the pinion should be "pointed at" the center bearing (so the rear u-joint is straight at rest).

i agree with Jspafford that the cap has been spinning in the ear for some time (seized needle bearing). it finally spun out, allowing the u-joint cross to slam into the ear, sheering it.

Wicked_Sludge said:

your carrier bearing location sounds acceptable to me. unless there is a spacer under it already that can be removed, there is no way to move it up. you do need to get your pinion anxle fixed, however. the pinion should be "pointed at" the center bearing (so the rear u-joint is straight at rest).

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The center support bearing sits on top of the crossmember, so it should raise it if I put a spacer under it.

really? maybe im use to being under 4x4 trucks sorry about that.