Bronco with the shakes

[kidduniversity]

I just got finish driving my Bronco today, and I have not gotten to drive it in awhile. The last time I drove it it had soem shakes when going about 60-70 mph. I was going to my buddies shop to put on my new rims and tires and notice the shaking was alot worse. Pulled into a parking lot noticed alot of play in the rear yoke connecting into the differential. There is anywhere between 1/8" - 1/4" play. there is fluid leaking out the yoke area. I realize that my seal is gone and my bearing are bad. I do not know if my ring and pinion gear are messed up or not. My questions are: What would you do? Just buy another Ford 9" with a 4.11 gear? Take it all apart and work on it? I am not to familar with axles and working on them. My speciality is engine, interior work, sound systems, electrical, and basically everything but transimissons and axles. I understand basics, but Do not know how to work on them. Is anyone familar with this type of work and can talk me through it? It would be aewsome to get some of the bronco owners in the Charlotte area to help. Does anyone with diagrams showing the Ford 9" rear end. Like an assembally drawing and stuff. I can figure alot out by just looking at a picture. One last thing does anyone know is there anything else that might be causing my rattling and shakes when I barely try to accelerate, and when I am going over 60 mph? Thnak you so much for your time and look forward to your response.

 

[wildbill]

%) %) %) Are the bearing's bad or not you mite just need to replace the rear seal and ck. the pinon nut they can come lose and that will give you the slop. Also look at your Ujoints and slip joint as they can all cause trouble. A bad u joint will cause a vibration at upper speed's 50 on up most of the time. Good luck. %) %) %) Bill %)

 

[kidduniversity]

Thanks Bill I was looking at worse case scenerio. The yoke has shaked around causing the pinon gear to mash in and mess up the teeth. I was thinking and hoping it is just the seal and the bearings are gone. I has also been meaning to ask How do you know if you have a big bearing? Also how do you know what spline number you have?

 

[70_Steve]

How do you know if you have a big bearing? Also how do you know what spline number you have?

There is a wealth of information on the sponsors web sites. This link, to Wild Horses on-line catalog explains the various rear differentials in the Broncos.
http://www.wildhorses4x4.com/18.asp

Here's a link to Jeff's Bronco Graveyard Technical and Documentation Archive, showing an exploded diagram of a 9" rear.
http://www.broncograveyard.com/dia/6/fo9dia.jpg

All Bronco 9" differentials came stock with 28 spline axles.

 

[ken75ranger]

Also how do you know what spline number you have?

Count them. The might not be stock.

 

[BUCKETOBOLTS]

Is the free play in the drive shaft or the pinion? A stiff or worn out U-joint can make a heck of a vibration. The double carden joint at the transmission could have slack too. I'm not saying your pinion is not worn, but a 9" has 3 bearings supporting the pinion(thats why they are so strong). I'm not far from Charlotte. And would be glad to check it out with you. I have a lot of experience with differentials and tranny's. And the tools to fix them with.