I have some drive train vibration since I installed a toploader 4 speed in my 1956 Fairlane. I also installed a 1957 Ford 9" rearend.



My question :



How much angle is idea between the transmission output and the yoke on the rearend?



I have heard so many different things I don't know what is right.



Thanks

Jim


  Jim Rowe Elkhorn, NE

I don't know how much angle you have at the moment but as far as the needle bearings in your U-joints go they normally need about 3 degrees at least to wear properly and last a long time in a street driver application..

Dustin

Southern Oregon Y's Guy

http://www.facebook.com/?ref=home#/profile.php?ref=profile&id=1441322018

Ideally the axis of the transmission....and the axis of the pinion in the differential should be parallel. The two U-joints would then be inclined at equal angles.

When under load - the pinion may climb a bit due to spring deflections- and there are tapered shims around that will allow canting it down slightly (at rest) so that it climbs up near to the right position as the car is driven.

 
 Steve Metzger       Tucson, Arizona

You can also get a vibration from a worn front yoke or bushing in the tailshaft housing. If the vibration is there under power but goes away when you let off, check the fit for slop. If you can move the front yoke up and down in the tailshaft bushing that could be your problem.

http://ford-y-block.com 

20 miles east of San Diego, 20 miles north of Mexico

Guys,

Thanks for the fast replies.

John,

It does not vibrate when your foot is off the gas. It does vibrate when under load or on the gas. The yoke does have some play. I wonder, can the bushing in the tailshaft be removed while the trans is in the car?



Thanks again guys for your help!



Jim

  Jim Rowe Elkhorn, NE

Yes it can, but you have to have a special tool to do it.

Dan      Kingman Az.      86409

I have found that a loose tailshaft bushing vibrates while coasting worse than under load. Have you compared the plane of the transmission to the plane of the rear? Vibration under load sounds like the two are not in plane with each other.

Kenneth

Fredricksburg, Texas

Jim, i have fitted a few of the 9" diffs into 56 fords and not sure whats causing the vibration but could be tailshaft and uni,s, more than likely. Normally the diff saddle mounts need to be replaced with the original style saddles to fit back onto the springs correctly, and moved about 1/2" inwards, (if i remember correctly)and rewelded, this is important step where about 5-6 degree pinion angle should be set,  I must add that i have seen the springs levered across to fit the 9" diff in! not good!  What did you use for tailshaft and does it run true when car is jacked up and running in gear. Will be interested in what you find to fix the vibration.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Here is a link to a good site for drive line info and setting pinion angles.
http://www.iedls.com/

then click on education zone at top right corner for a pdf file.
marv

Jim.  Let me know if the tailhousing bushing is indeed the problem.  If it is, I’ve an assortment of tail housing bushing removers and I’ll see if there is one here specific for your transmission and if so, I’ll drop it in the mail.  I’m assuming you have the 28 spline tailshaft.  Be sure to check the driveshaft yoke for wear also.

Lorena, Texas (South of Waco)