Rear pinion setup help

[Nfrancic]

I think I’ve rear all the posts on this subject but can’t seem to figure it out. Here’s my setup:
- 4” Tera flex lift with single adjustable upper and lower control arms
- SYE and double cardan driveshaft
- adjustable rear tack bar

I’ve centered the axle and set lower control arms so the bump stops are centered and full flex.

My transfer case yolk is at 7 degrees. Rear pinion 11 degrees and driveshaft is at 27 degrees. I measured the driveshaft slope with a string since the 16.5-22 shaft doesn’t seem to fit right now.

Is 27 degrees too steep for the driveshaft? I’m not sure if I could even raise the pinion that high. The lift did come with a 1” transfer case drop but i thought I could avoid that because of the SYE.

Any suggestions? Should I try to raise pinion to 25-26 degrees? Should I do the transfer case drop?

I appreciate any guidance!!

 

[Jerry Bransford]

Pay no attention to the angle numbers, you only need to angle the rear pinion shaft up so it points directly up the driveshaft and at the DC (aka CV) joint.

Exactly like this....

 

[machoheadgames]

From the factory, your axle is pointed up at least 6-7 degrees. So you're only 5 or so degrees above stock right now. Something to understand, is that as you lift the pinion, you also lift the driveshaft.....so if you add 1 degree to the pinion, you will likely change the difference between the two of them by probably at least 2 degrees. That depends on how long the driveshaft truly is, it's less drastic on a longer shaft but it still applies.

In other words, if you're at 11 degrees, which is about 5 degrees above stock, another 5 degrees will probably bring your driveshaft down to roughly 22 degrees, while your pinion will be up to 16 degrees. A few more degrees and you'll be there. You will NOT need to lift the pinion another 16 degrees (27-11) to get the two even with each other.

For a 4" lift, 10-15 degrees pinion angle over stock is needed. Depends on the transfer case skid, automatic or manual, Dana 44 or Dana 35, super short or standard SYE, etc

Short version: adjust the angle as needed until where it needs to be. All of the above is just to explain why you need to do that. Get the pinion to be 1-2 degrees below the driveshaft and you'll be set.

 

[Painfultruth]

 

[macleanflood]

Biggest question is does it vibrate or make noise?

No point in being too picky if you don't have a problem!

-Mac

 

[Nfrancic]

Thanks everyone. I have no idea if it vibrates yet. I set the pinion angle today but the drive shaft is about 1” too long. Lesson learned…shouldn’t have listened to 4WP and purchased it before everything was setup.

Really appreciate everyone’s guidance!