Hi I am sure this has been asked and answered many times befor,and I have read some of the answers,...but I am still not getting it...So here is my question...The slip joint is 5 degrees down,....the pinion flange is 4 degrees down,...and the drive shaft when in place is 3 degrees down toward the rear,....the trans is centered, and the frame is level,and the weight is on the suspension,...what should I raise or lower to get the proper pinion angle and in my case what should that be?....Thanks for any info....Miller
If the ****** had a laser shooting out the back and the pinion had a laser pointing to the front neither laserbeam would intersect, they would be parallel to each other when viewed from the side.
Run the trans yoke and the pinion parralel to each other then put the pinion 3 degrees down from that. Thats how I would do it.
The transmission output shaft angle and pinion angle should be the same, under operating load. If you have leaf springs, then set the pinion 2-3 degrees down from the tail shaft angle, so when the spring wind up, the angles become parallel. With links, this is not necessary, save maybe a degree for bushing compression. If I am reading you post correctly, your tail shaft tilts down 5 degrees from horizontal, and you pinion, 4 degrees. I think you are already done.
the general starting point is 3 deg. down on ****** 3 deg. up on pinion, but it depends on how high or low the vehicle sits if it sits very low or very high you have to factor the angle your putting the drive shaft in , wether its climbing up hill or down hill this changes the angle of the pinion and tail shaft . the starting point is ***uming your drive shaft is at 0 degrees which most are not, in the case of my car i did the 3 and 3 it had a vibration because the drive shaft climbed upward toward the rear putting the pinion in more of a bind. the rear was so much higher in the car than the trans. i had to take out 1 deg from both to correct this to ease the angle on the pinion. sorry if it sound confusing.......if the 3 and 3 dont give you any vibrations than it will be alright......
Look at the drawings near the bottom to this post. http://www.ffcobra.com/forums/showthread.php?t=136738&highlight=Pinoin+angle
Yes the trans tail is down 5 and the rear is down 4....I used a angle gauge....So what do I do if anything???.....Thanks Miller
Unless I am mis-interpreting the above, it is incorrect. If the trans shaft is down, the pinion should be up..........if both are down they cannot be parallel.........and they need to be....or at least close to parallel Tman said it very well....................... Ray
Parallel..is the key from what and the way i am reading this/...you are not parallel. up with the pinion on the rear until it is parallel with the trans output
Raise the pinion at least 6 to 7 degrees from it's present position. It should be 'up' at least 3 degrees from level and could go as much as 5 but that would be the 'up' limit, given the trans angle. Ray
I think that only applies to "normal" ch***is situations. "IF" we're talking some nutty, 10" "Z'd" frame, that idea would put the u-joints in a terrible angle
The tailshaft and the pinion do not have to be parallel, you just need to have the same, or nearly the same included angle between the tailshaft and the driveshaft and the pinion and the driveshaft. For example, right now you're 5* down on the tailshaft and 3* down on the driveshaft. Included angle in the front is 5-3=2*. the pinion is down 4* and the driveshaft is 3* down to the rear, 3+4=7*. 5* difference between the two, probably a little too much. Usually the fix is trial and error because as you rotate the pinion the angle of the driveshaft also changes. As you rotate the pinion up the included angle in the rear will get smaller as the included angle in the front will increase until you find a happy medium. As somebody already mentioned if you're on leaf springs you'll get some pinion rise under acceleration that you'll have to accout for.
OK, if the centerlines of the trans tailshaft, and centerline of pinion aren't any further apart (nearly even), in either direction from a normal ch***is setup...I shoot for about a 1 1/2 degree difference from the pinion centerline to the driveshaft centerline. The same 1 1/2 degree difference for the trans output shaft centerline to the driveshaft's centerline. This with a $10, magnetic angle finder from your local True Value Hardware store
See above post. I'm not sure what you mean here. You need to correct the pinon's relationship to the tube (d-shaft), and the trans output shaft's relationship to the tube. If you're saying your tail is 5 degrees down relative to the ground? That means nothing
I was being basic in my description. It blow me away how folks **** this up all the time when it is REALLY simple.
Yeah, I should have wrote it pinion 4 degrees up from horizontal. What? It makes perfect sense, inside my head.
I follow the general principle, but what is the solution when the diff is higher than the ****** as could be the case in some very low cars??? Just changing the subject slightly, a buddy of mine lowered his 1936 with the torque tube still in it and lost most of his oil during a road trip as the diff ended up higher than the ****** end of the tube once his vehicle was loaded.
I do mine like TMan said - as close to parallel under static load as I can get it. I think what screws most guys up is the impression that under load the rear winds up and with it the pinion .......... which it does on acceleration BUT it drops back to static position when you hit cruising speed and under deceleration it will drop below static - momentarily. Take a ride in a pickup without a box on the back and watch the pinion move - that's how I know this!
Maybe this article will help. It is from FSC magazine (Fastest Street Car), written more fore drag racing but applicable to all drivetrains. http://viewer.zmags.com/publication/95d2913d#/95d2913d/50
The Jalopy Journal
