pinion angle measuring locations

[greencactus3]

since there have been some questions as to WHERE to measure from for pinion angle corrections,

this below diagram applies only for 1pc driveshaft trucks.
this means all std cab shortbeds, 2nd gen std cab longbeds, all blazers.

if you have an ext cab of any sort, or a first gen (pre 93) longbed truck, ignore this diagram.




for 2pc driveshaft owners, see this thread

http://www.s10forum.com/forum/f12/pi...xt-cab-184873/

Quote: Originally Posted by grndscrpr03

Ok I will be trying to get a how-to on everything written up within the next week or so, but until then I'll give the cliff notes here.

Let me start off by saying this:
Stock (4-cylinder and V6) S-10 extended cab trucks have a mis-alignment of:

*2° to 3° between the transmission output shaft and the front driveshaft.
*1° to 3° between the front driveshaft and the rear driveshaft
*4° to 7° between the rear driveshaft and the pinion shaft
Now you really only need to get 4 measurements--(1)the transmission output shaft, (2)the front driveshaft, (3) the rear driveshaft, and (4)the pinion shaft on the rearend.

You need to use an angle finder, or inclinometer to get these angles. They can be bought for around $10 or so and look like this.

Now once you have these 4 measurements you can figure out the differences between each point mentioned above. You have to take the transmission output shaft angle and compare it with the front driveshaft measurement to find the overall angle.
EXAMPLE--if the transmission output shaft is at -3 degrees(pointing down) and the front driveshaft is at -2 degrees then that is a 1 degree difference.
Next compare the front driveshaft angle with the rear driveshaft angle.
EXAMPLE--the front driveshaft is at -2 degrees and the rear driveshaft is at -4 degrees then there is a 2 degree difference between them.
Next compare the rear driveshaft angle with the pinion shaft angle.
EXAMPLE--the rear driveshaft angle is -4 degrees and the pinion shaft is at +4 degrees then there is a 8 degree difference.

Now the goal is to get as straight of a line as possilbe from tranny to rearend. To improve the angle between the transmission output shaft and front driveshaft then tranny and/or carrier bearing crossmember spacers need to be used. However this really only needs to be done if the angles are off by quite a bit. If only off a couple degrees, like in my example, then I wouldn't worry about it. However there will more than likely be a big difference in the rear driveshaft and pinion shaft on the rearend and this will need to be fixed. In my example the rear driveshaft was pointing down at 4 degrees and the rearend was pointing up at 4 degrees. So in order to correct this the rearend would need to be turned down around 7-8 degrees.
Now chances are your truck isn't going to be off that bad, this was just an example. If you have any questions lemme know. Also if you get your measurements and then don't know where to go from there, lemme know and I can help you out. Hope this helps you!!!!

while i have your attention, i will repeat what i always say.

no matter if its a mild drop or a slammed or bagged truck, ALWAYS measure your pinion angles and correct them, as it will wear your ujoints mostly, but it can wear away more expensive parts such as your transmission and rear end, and believe it or not, theoretically it can wear your rear tires and brakes as well.

you can pick up the angle finders at most good hardware stores (home depot is not a good hardware store)

or harbor freight also has them for just about $5

well worth the cost.

http://www.harborfreight.com/cpi/cta...emnumber=34214

[98layinframe]

so why do you have the rear end pointing down so much? everything that ive read allways tells you that with a single piece driveshaft that uses regular u joints (not cv joints) should have the angles within 2* of each other and the angles should be equal but opposite. So shouldnt your rearend be at 0* also in that pic??

[greencactus3]

Quote: Originally Posted by 98layinframe

so why do you have the rear end pointing down so much? everything that ive read allways tells you that with a single piece driveshaft that uses regular u joints (not cv joints) should have the angles within 2* of each other and the angles should be equal but opposite. So shouldnt your rearend be at 0* also in that pic??

it kinda depends on how weak your leaf springs are.

technically you want the "correct angle" purely based on efficiency of the universals, the matching angles would be good, but due to flex and compliance, i have read you want to have some downward angle on the diff side, because under acceleration you will have the pumpkin twist "up", where it should match the trans output angle.

so say your leaves allow for 4 degrees of pinion angle change due to moment from the tires (extreme case)
so then if your static diff angle is down 2 degrees and the tranny is at 0 degrees, under acceration, the diff angle goes to upwards 2 degrees.

something like that.

3 degrees may be excessive, but it really depends on the compliance.

even with linked setups, you want a small amount of downward angle at the diff as opposed to a weak leaf pack, but there will ALWAYS be compliance.

as for braking, im assuming the opposite is not as critical because of weight transfer etc.

i cannot say how much downward angle you would want, but within reason, you always want more downward at the pumpkin compared to the trans, than upwards.

*to save my ass if im way off*
-the 3 degrees was just a drawing. not to be though of as the ideal difference lol

[98layinframe]

ok that makes sense with the spring wrap and all..

[Bmanxer]

So how do we go about correcting the problems if we find them? What about the blocks that have the pinion angles already in them?

[greencactus3]

Quote: Originally Posted by Bmanxer

So how do we go about correcting the problems if we find them? What about the blocks that have the pinion angles already in them?

you can use the angled blocks, or you can use shims on top of blocks to correct the driveline angles if they are too far off

[terryl]

Measuring points for 2 piece shafts with 1 u-joint and 2 double cardan joints (CV joints)

Tranny output shaft


First drive shaft


Second drive shaft


Rear pinion

[Lowsonoma03]

are we supposed to be able to read the gauge in every pic or what?

[terryl]

Nope. Just reference points for taking measurements.

[02_Black_XBlazer]

Thanks for the info, gc3 and terryl. I know there's plenty of threads about pinion angle around here, but this one breaks it down into simple pictures I can understand. The pretty colors are nice to!

[greencactus3]

i forgot to bring the angle finder to belletire today when the truck was over the pit getting aligned......

dammit. and noone there had one lol

so i guess i have to crawl under the truck still

[ZQ8 Blazer]

So terryl... Wanna sell that catalytic converter in your pics? I'll give ya $10 for it.

[ZQ8 Blazer]

Damn, waited 10 min (exactly) to edit my post

I think I might measure mine to see what it's like, although I'm still not getting front bump stops Thanks for the how to.

[SSzq803]

http://www.airridetalk.com/articles/...nt-enigma.html

[SSzq803]

Im having a problem with vibration of the driveline on my truck found this to be helpfull.maybe it will help others