Topic: Driveshaft Vibration

[toymech]

 Ok guys,I kinda messes up when I was cutting out my old rusty U joints when putting new ones in. I forgot to mark the driveshat before I torched out the joints. I have a vibration around 40mph and ive tried switching the front yoke around on the shaft splines. Any ideas before I bring it to a shop to have it balanced? Thanks

[whiteman]

When you change a U-joint it should not change the balance of the shaft, you most likley warped the yoke or the shaft. 
You can either find a new drive line and instead of torching out the U-joints, select the proper size socket and a nice heavy hammer and beat it out, with it flat on the ground this will prevent it from warping.  Or you can use a press if you have access to one.

Or have the original one balanced 

[toymech [OP]]

  Warping the driveshaft,nah. I didnt use that much heat. I found a loose companion flange on the transfer case. I guess this is common since it happened to my last Toyota trucks. If this doesnt work im getting it balanced. I figure if the yokes warp the U-joint caps woulda been a mother going back in,I didnt have that problem. Thanks for the reply Whiteman.  Mike

[79coyotefrg]

  so you sliped the shaft apart at the splines??  not a big deal  to find where it should be  the shaft  must be in phase

imagine the shaft with the u joints removed, and a wood dowel pin  fitted thru the yoke and thru your work bench to hold it square to the bench,  the other end  has to be the same,  if its off 1 spline in the slip yoke  it will vibrate,  so once  you do this  the weights on the shaft are in line or 180* off,  are ya following me ??

[whiteman]

Makes sense coyote, but after hearing that your T-case flange is loose, i would garuntee that that is your problem.
My friend had a loose flange on the T-case and his truck vibrated worse than a Cat D8 doing 90mph on the freeway.  i mean it was bad.  I would fix that first 

[79coyotefrg]

i just got done building my shafts after my dual cases,  cut a rear section of a 2 peice rear shaft to make my rear shaft and just cut my old rear shaft , and cut the cv off my old front shaft and fitted it onto the old rear shaft tube, 

i ran down the road yesterday to see how the rear shaft handled  and it was great

im sure the front will be the same when i weld it up tomorrow

[79coyotefrg]

truck vibrated worse than a Cat D8 doing 90mph on the freeway. 

DDDAAAAYYYYYYYUUUUUUUUUUUUUUUUUUMMMMMMM


them be some serious vibes.  when i was working on the interstate  we had to get our 6 to the other end of the Job,  the transport driver tried walking it on sideways and bent the trailer,     so  i got elected to walk the sucker 4 miles to the other end,   over a mile was down  the old concrete slab 

  might be why i have a ruptured disc now

[toymech [OP]]

 Hey,thanks guys. Im going to torque the flage down and see how it goes. Its all making sense now,the vibes go away mostly on the decel and high speeds. On the gas I notice the rear veiw mirror shaking=yeah,that bad. Im kinda used to it from the LTBs. I have another question. Im debating on putting 33s under my truck. Not sure if theyll fit or look right. I have a 3 inch Downey IFS lift (well theres no rocks in jersey) and 4.88s and a Detroit in the rear so far. I dont like body lifts or any IFS lift kits that slam the front diff to the floor. What do you guys think? Id SAS the damn thing if I wasnt that concerned about getting pulled over every 5 minutes around here and I knew I could get it inspected. Oh well,maybe one day ill be out there playin in the rocks of the Rubicon. Later.  Mike

[whiteman]

Just for insurance, if that flange is loose you may want to drain the T-case and pull that first T-case cover on the back side.  If you use this link as a reference http://www.marlincrawler.com/htm/transfercase/470install/installation.htm  You want to remove cover #4 and then look at steps 7 and 8 the two speedo gears and the bearing were shot on my friends, and once we replaced all the parts the wobble was gone and no more vibration


I have pics on my computer at home if I have time i will try and post some pics of he damage caused to the gears. 
And as far as those 33's go, they should fit like a glove, infact you can fit 33's with an add-a-leaf and tourqed torsions.

Good luck

[79coyotefrg]

yea man  33's  should fit fine