Engine/Transmission (1998.5 - 2002) Broken Rear Axle Input Flange?!

[Sean Flanagan]

You broke what? I asked my buddy when he called me...



Apparently while backing up his trailer, he put it in first gear and let out the clutch suddenly while still moving backwards. He said the back u-joint twisted out of it's "u-bolt" and broke one of the "bolt hole ears" off of the rear axle input flange for the drive shaft!



Anybody else ever have this sort of thing happen?



Also, is there an easy way to get that input flange off of the rear axle? When I had to replace the pinion seal on my truck, I had to put on a great big puller, beat the snot out of it, then heat it and beat it some more, to get it off.



His truck is the same as mine... see signature...

 

[Whitmore]

Sounds like he broke the pinion yoke, take the big nut off and use a puller to remove the old one , Have him also buy a new U-joint too, get a solid one, the greasable ones are hollow and are not as strong. Check the driveline for tweeks and especially where the U-joint bolts in.



cheers, Kevin

 

[sag2]

Tell him to be careful putting the nut back on. Improper torque and you will ruin the bearings for sure, and possibly the ring and pinion if you drive it adjusted wrong. Get the service manual and follow it exactly. You should measure the turning torque in inch pounds before you pull the old one. But with the ring gear installed it will be a little hard to tell the proper turning torque. As I said, be safe and use the manual. Torque is somewhere near 200 ft/lbs so you need a LARGE torque wrench.

 

[Bob4x4]

You should definitely use a puller up to the task,replace the pinion seal while you have it apart and tighten the pinion nut to 440-500 ft lbs on the Dana 80.



Bob

 

[truckstom]

While your at it take the drive shaft(s) to have them checked for straightness(is that a word?) Sounds like a lot of strain on the drive train till the weakest part let go. Doesn't take too much to kink that drive line... .....

 

[DSiemens]

pinon yoke puller

If the 4 u-joint bolt holes are still usable, make a pinion yoke puller. You need at least 2 bolt holes for this to work. Take a heavy (3/8, 1/2) steel plate. Measure the distance of u-joint bolt holes from yoke. Drill hvy plate with this pattern. Next, find center of pattern, drill & tap for a 1/2 inch or so bolt. Use longer than stock u-joint bolts to attach plate to pinion yoke. Tighten center bolt and yoke pulls off easy.

Make sure pinion nut is removed before pulling yoke. Also it is a very good idea to measure bearing preload. A new pinion seal will add about 5 inch lbs to first preload reading taken. The factory manual is very good to have. You will also need to make or buy a pinion yoke holder to remove pinion nut. Also, make sure that the driveshaft is checked to straightness.