dhall50

So I am trying to track down a bad vibration I get around 35-53mph. Makes my trans wiggle and my bed shake not to mention the rest of the truck. I swapped drive shafts and that made no difference.(I have two new joints to put in my old shaft for preventative maint but they are not bad right now.) So I read a little about companion flanges. I removed my drive shaft and the transfer case flange had not play that i could tell. The rear diff flange has very slight play up and down and I am hoping this is my prob simulating a bad U joint.

Where do I go from here? Could the flange nut be loose? Do I just put the E Brake on and re torque it?(90ft lbs?) I am not even sure how to un stake it. If that doesn't fix it how big of a problem am I in for? Thanks

waskillywabbit

iTrader: (-1)

Factory Service Manual
www.ncttora.com/fsm

Rear pinion seal/bearing

:wabbit2:

4Crawler

iTrader: (3)

Info on un-staking and torquing pinion flange nut:
- http://www.4crawler.com/4x4/CheapTri...eal/index.html

I find a loose flange tends to vibrate only when backing off the throttle, when there is no load on the driveline.

Also check the shaft alignment and phasing:
- http://www.4crawler.com/4x4/CheapTri...n-Measurements
- http://www.4crawler.com/4x4/CheapTri....shtml#Phasing

dhall50

So after reading it looks like a ton of work just to replace that bearing and the torque mentions 173ftlb for a 7.5 and 253 for an 8". Seems like a lot. Probably way beyond someones ability that hasn't touched a diff before? Can I not just re torque that bolt without measuring preload etc to make sure it isnt just loose like others I have read about here?

zwhiz

so i had that same vibration that you are talking about and i ignored it for a month or so... about two weeks ago my diff made some terrible noise and grinding and started to lock up. i barely limped it home. i finally got to tear into it today...found my pinion bearing and seal were blown out...bad... here are some pics of the carnage
the gears on the left i pulled out of the third you can see its gouged pretty bad


bearing was just a mess....

zwhiz

i'll let you know how replacing it goes....
just dont let it go too long and have what happen to me happen to you!

dhall50

Yikes. A buddy came over and we looked at the flange and he concluded that since all of the play was in the flange and the shft itself was not moving that it was maybe just loose. We unstaked the nut and it was easy to turn. Re torquing it removed the play at least for now. I have been dealing with this for a long time. I still have misc vibrations but this was a big help. Interested to see if it lossens up again. Let me know how it goes.

PS: My buddy said a used 3rd member goes for like $75 at the junk yard? I will prolly go that route if mine continues to give me issues.

zwhiz

ohh nice. youre lucky then! i just procrastinated until my exploded.... ya when i took mine off the flange nut was hand tight, not good. that was probably the root of my problems.
oh believe me ive look at junkyards for the last two weeks. every yota had the 3rd member pulled at u-pull-it and other junkyards wanted 250 for just the 3rd.

dhall50

Whoa!

foutz

Mine did the same thing but it would start when i would take off and stop at about 55. The nut backed all the way off and eventually the flang came completely off.

zwhiz

daaang thats kinda scary