The Stovebolt Site Forums The Shop Area Engine Shop Pinion angle

When I sub-framed my 53 3100, it lowered the front about 6". Thats a little more rake than I wanted so I lowered the rear about 2". My question if I lower the rear much more where is my pinion angle going? Will it ruin the U-joints? I assume there a minimal amount of pinion angle required? Thanks, Phil

If you do a search you'll probably find hours or reading on pinion angle. I also think ther eis a tech tip here about it as well. Just check the angle you have. I believe the angle should be about 2 degrees negative. Some say check the angle on the engine at the starter, some say transmission ect ect. I check mine with the starter then go to the rear end and set it.
I think the "officially" the angle should be between 1 to 3 but I'm sure someone with a better memory than mine will chip in here. Good luck.

This Tech Tip on Driveline Set Up ??

And from that Tech Tip
There are some excellent manuals (instructions) linked in the tip.

Grigg

As long as each u-joint has some angle, 3 being the most, and that includes up and down and side to side, then you will be all right. From what I have read, if the transmission to driveshaft angle is about 2 degrees, then the driveshaft to pinion should also be about 2 degrees. This is where the angle finders come in handy. The angle of motor and pinion to the ground makes no difference, you want to know the angle between the driveshaft and each end. A u-joint needs some angle so the inner bearings get worked around, if its straight, the bearings just get looser as they dig in.

Joe

3 to 5 degress down .When u set the engine in put a level on the top of the intake manifold , carb removed!Close to level is better for a carburated engines base line installation It should be close to 0 degress. The truck should be assembled as much as possable all weight on it so these numbers dont change much.There can be a lot of factors leaf springs coils what vehicle is built to do drive ,race ect.

I disagree with the first part of your explanation.
After rechecking the Spicer Driveline manuals I can't see how the engine being level or not makes a difference, obviously you don't want it standing up on end, but 0 degrees or 5 or even 10 is not important.
As Joe mentioned above it is important to have the engine and the pinion parallel. The engine or pinion angle in relation to horizontal has no effect on the driveline, the relationship between the components of the driveline is where it matters.

Having the truck as close to final weight as possible and assembled when you measure and correct the pinion angle is an excellent point not to be overlooked.

Grigg

Check this link could be helpful to many people . http://s897.photobucket.com/albums/ac176/webstershotrods/1953%20Chevrolet%204400/

If it's 0 at rest, it remain 0 only until you try to pull any load, then the pinion nose rises. How much nose down depends on suspension stiffness, engine power, max load, etc.

With the weight of the engine, and everything attached to the engine that is going to be attached to the engine, raise the vehicle up being sure that the weight of the vehicle is on the axles. Put an angle finder on the bottom of the starter and get that angle. Next put the angle finder on a flat portion of the pinion. Turn the pinion until the angle finds the same angle as the one on the starter. That's it. You can buy angle finders for a few bucks at Harbor Freight Tools.

You had enough input yet! Heres a bit more, use a tie down strap and pull the axles down if you don't have weight on the chassis, it will get you pretty close.

The main thing is to not set the driveline in a straight line to the motor or axle.

Joe

Neither parallel, horizontal, nor "level" matter.
BTW: the carb flange mount is not always parallel to the ground, or to the crankshaft.

Has some broken links
Use this new link for the Spicer Driveshaft Installation Guide
and this link for the Spicer Driveshaft Application Guidelines

Sorry about that,
And in the future the publication number should stay the same and can be searched for on the Roadranger website if the direct links fail again.

Grigg

Grigg, thanks for the link, they are a great referece as I am chasing down a suspected driveline vibration.

thx again

Grigg,

Those Dana-Spicer pdfs are very good. Thanks much. The other "Links" do not seem to work; it seems that if one uses the name "Links" for a link, it goes to the Stovebolt Links, regardless of the writer's intention. Same if one uses Tech Tips for a name, I think.

Hoyt

Hoyt - that's a "feature" of the forum software for most of the 1inks across the top of the page, you can subvert it easily by modifying the words a bit

Bill

Y'all are welcome, and thanks for looking at them.
As you can see they are invaluable and cover pretty much every driveshaft question with real answers and figures, not hearsay and guesses.
I wish more folks would read through them, at least look at the pictures.

Grigg

I owned a driveline shop and built a lot of drivelines as many of you know. We always used he Spicer information as our guide (they trained us) and never had any problems, at least no one ever brought a shaft back to my shop complaining about it. We build car, truck, off road, racing and heavy equipment drivelines and the same basic rules apply to all. It is Gospel as far as I am concerned. I've read a great deal of stuff both here and in numerous magazines written by people who didn't understand the issue. Just refer to the Spicer link that Grigg posted and you will have no problems if you follow the instructions. Really pretty basic and simple stuff.

Just wanted to thank everyone that responded to my post, and for the information provided.