Pinion angle

[DirtDonk]

high arch, 12in longer than eb springs

I also have low gears and run 3500rpm down the freeway, which means the

Im sure the angle goes up higher when under some load just driving normally.

Not exactly apples to oranges perhaps, but more like Honey Crisp to Gala, or maybe small Fuji to large Fuji.;D
What I mean is that in theory at least, your axle-wrap should be much less than a standard suspension EB like most of us have. It's one of the reasons to go with longer leaf springs in the first place. Lowers the twisting of the spring under torque.
I'd love to see video sometime of the rear pinion of Broncos set up differently for comparison. Especially yours! I've personally experienced slight vibrations when the rear pinion was at zero degrees to the driveshaft. Not as bad as other conditions, but still there.
First video could be a normal stock suspension, next one with aftermarket replacement leaf springs, then one like yours. Perhaps even with and without anti-wrap devices.
And also different gear ratios.

We have some video on the NorCal site of an EB with aftermarket springs and 35" tires, before and after an anti-wrap device install. I'd have to check the gear ratio, but they were very good videos of rear axle-wrap/spring-wrap/pinion climb (whatever your preferred phrase is).
I think it would be great to have a full complement of vids here on this site in one thread we could all look at to gauge the results of different modifications.

In my theoretical example, lower gearing means less pinion-climb under some conditions, and longer springs means less pinion climb than stock length springs.

the pinion ended up about 1/2 to 1 degree "up" from the drive shaft.

if your within 2 degree in either direction i think you are fine.

If the pinion is a little high on most normal Broncos you can definitely get a vibration. In some cases a very noticeable vibration, under acceleration or high speed cruise when pushing wind puts the throttle down a bit more than an easy cruise. Which is why I'd love to see video of different rear ends.
Of the Bronco kind that is...%)

If Mitch would sit still for a few days at a time, I'd try to get him to do a series on it at WH since we have a lot of different rigs to shoot from.
But nothing like yours, which would be a great reference.

Paul

 

[71 CA Bronco]

All good points here. I figured if the leaf springs sag a bit over time, I'll put the extra springs I removed back in. I did do anti-wrap perches which should help a little.

Paul you need to get Mitch on it. It would be great to narrow down a good number to shoot for that we can all agree on. The method discussed here by "ArmyNavy17" on figuring out how far to roll the perches is really how this discussion took off. It works well, I shot for 1 degree and got 1.1. Now that surprised the heck out of me. That is a very accurate way to roll the perches and account for the driveline angle change no matter what angle you are shooting for.

 

[Steve83]

Ford published this TSB about driveshafts & u-joint angles:

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[71 CA Bronco]

Good information, Thank you for sharing.

If I read that correctly, Ford states 1/2-3 degree angle difference is recommended between the pinion and driveline. Take half the distance (midpoint) and you should shoot for 1.75 (1-3/4) degrees. But if you land between 1/2 and 3 degrees difference in your final install numbers you are good to go.

I feel comfy at 1.1 degrees. I'm off the middle ground of what Ford recommends by about 1/2 degree. This is well within the 1/2-3 degree tolerance given by Ford.

This also confirms what many have said on here that 1-3 degrees difference is ideal. OK, wiping the sweat off my brow now. ;D

 

[Steve83]

Even though it hadn't damaged the u-joint, this one was a FAIL:

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