pinion angle

[Captkaos]

Do not stack them.
You need to tell us what your numbers are when you measure them and how are you getting them.  A shackle flip shouldnt ever need more than 1 2 degree shim for correction.  The pinion is SUPPOSE to point up so if you are trying to make it parallel with the ground, you are going about it the wrong way...

[SBC384]

i dont have the first short stiff spring in doest it make a differance ? checking pinion agle now  bbl

[Captkaos]

The helper spring makes no difference at all...

[SBC384]

i put the helper spring in and took the first spring out with the the 4* wedges installed now the rear end angle is 4* looking up
but im sittn on the bump stops pretty hard... going to put other spring back in tomorrow
ounce again thanks for all the help despite all the remedial information im giving yall.. Chris

[HAULIN IT]

Sbc, Something is a miss here. I had asked before, your axle is BELOW the springs, correct? My truck is lowered more than 4", more like 5". I still have a little over 2" till the bump stops hit the axle. Is there alot of weight in your bed? You had said "The driveshaft won't go in". This all sounds like too drastic of problems for hanger/shackles. I'm wondering if someone had done something to the truck before you got it (lowering springs,axle flip)? How are you coming up with the + 4*number? It's not impossible, but just doesn't seem right. Lorne

[Captkaos]

I REALLY would like to see a visual of what we are working on too...

[SBC384]

axle is under springs...with the angle finder shows 4* it was on the bump stops because i had to many leafs out.. put them back in looks to be fine i guess i was thinking angle should be down more.. will know more the weekend when i have more time. will try to get pics kaos..
thanks again

[HAULIN IT]

Sbc, Are you saying when you put the angle finder on the rear yoke, it is 4* from 90?

[SBC384]

yes, angle is slightly pointing up.  hey read my post in 73-87 trucks section under rotors
thanks

[HAULIN IT]

Ok, Are you sticking the angle finder on the end of the yoke, then rolling it out on the top...1-2-3-4* & now it reads 90*? If so this isn't correct. The pinion angle has nothing to do with the ground,level,plum,horizontal,vertical & the like. As was mentioned earlier, it is the angles of the transmission output shaft & the rear end pinion. The vehicle needs to be on the ground (or the axle supported by stands). Now once you get the sum of the two numbers to equal 180* (ideal) For a drag race set-up with leaf springs, the pinion should then be rotated down 4-6* from this point, as I said earlier, how much depends on how well or poorly the suspension controls the rotation. I hope this gets you going in the right direction. Lorne   

[Captkaos]

As Haulin it, said, the floor has nothing to do with this.  It is the drivetrain angle you are working with not the floor.  If you are getting 86 degrees pointing up, you are only halfway there... 

I would put it on jackstands  and pull the driveshaft....   But, you can measure off the face of both, with an angle finder on the output seal flange lets say you come up with 86 degree (trans is pointing down) that is -4 degrees drivetrain angle.  Then go to the rear yoke and put the finder across the u-joint saddle (driveshaft should be removed) and it says 84 degrees (pointing up) that is +6 degrees.  Then add the 2 together -4 + +6 = +2 degree pinion angle, for a leaf setup you would shim it up 2 degrees so you would have the pinion +8 degrees.

[SBC384]

thanks guys going to work on it more tonight going to pinks all out tomorrow

[HAULIN IT]

Chris, Meaning no disrespect, but I'm not sure I agree with your last post. We go about how we get the numbers a little different, so I don't want to say "your wrong!" however the numbers aren't adding up. The way I've always figured it is in a "normal" vehicle the sum of the two numbers should always equal 180*. As I stated earlier, on highly lifted 4x4's this likely is not possible because the U-joints will bind. Also on a "pro street" type vehicle, the same problem only reversed. The real problem I'm having is with the +8, this to me is incorrect. How you went about getting the +2 on the surface seems ok, just not the same way I do it, or relate to it. On a drag race set-up, the pinion should be, again, depending on the ability of the suspension to control the rotation, DOWNWARD from the "equal to 180 number" (about 4-6* on leaf spring vehicles) not necessarily downward to the ground or looking at it, just downward from the "correct phasing". Say you come up with 88* at the transmission, the rear end (assuming you don't want/need to move the transmission) has to be 92* to be in "correct phase", from that, the pinion should be DOWN 4-6* from this point to allow for the rotation upward of the axle as the power is applied, ending up ideally straight with the driveshaft, again this is not ideal for normal vehicles (some droning likely will occur) at a steady speed. Where's Vile with "proper procedures for pinion angle" out of some manual? There is always more than one way to skin the cat, there are other "special tools" that go in the U-joint caps & take the reading differently, ect. I'm just not sure we are all on the same page here. On another note, I feel the pinion angle itself can not effect traction (like many believe) unless it is so far off it binds the U-joints & stops the rotation of the axle, it's the changing of the pre-determined amount of rotation (suspension changes) that effect the traction. Feel free to all to agree, disagree, comment, ect. As I said Capt, Please don't take this to mean anything but to clear up a few things. Lorne       

[VileZambonie]

Where's Vile with "proper procedures for pinion angle" out of some manual?

Excuse me dude, but if you are insinuating my knowledge comes out of some pop up book you're mistaken. I'm not the one photo copying and plaguerising everything in text be it internet or your old how to books. All of my information comes from my own knowledge and I rarely quote print unless I'm copying and pasting a service procedure, TSB, or spec's. I don't know why you are dragging my name in here only to take pot shot's because you still have a diaper rash over your last rant or something.  Stop trying to sound like a know it all and put it in plain English with a viable procedure if you really want to help this guy set his pinion angle. There are many simple methods of checking pinion angle. It's a simple comparison of the 2 connecting driveline angles. Spend a little less time trying to be Mr. right and try to be Mr. Helpful here Lorne.

[SBC384]

ive got 85 on rear end and 95 on tranny = 180  is this going to work?
thanks