Pinion angle adjustments question...

[skwerl]

^ That image confuses me more than it helps me. Also, the gauge face drawings don't make sense considering their orientation.

Play along with me for a second. Let's start with an assumption that the transmission is perfectly level (I know it won't be most of the time, but play along). So the Transmission angle would be 0. Now let's also assume that the rear pinion is at approximately the same height as the transmission. If you took a laser pointer and lined it up perfectly with the pinion flange, would the laser be pointing above or below the transmission?


All I'm trying to determine is which way the -2 degrees should go. Do I want the pinion flange pointing above or below the transmission flange (if they were at the same height)?

 

[fdjizm]

The number being negative or positive on the scale depends what side you're measure from. If I measursed from the passenger side I would have +3 on the trans and +1 on the pinion, which is still a difference of two degrees with the pinion facing towards the ground. I just used the measurement on the driver side because of all the talk with the negatives so I wanted to read it as a negative.

from what I've been reading the pinion rotates upward on a launch so what you are doing is making it so when it does roate upward it will end up level with the trans flange. instead of point towards the sky.

So right now if I took a laser point and my trans flange was level with my pinion flange, the laser would be pointing slightly below the trans flange coming from the pinion flange. The theory being compensating for the upward rotation of the pinion on launch.

I think if you angle your pinion flange up with respect to the trans flange, on launch you're going to have some serious bind in your driveshaft joint because it's just going to go up more.

 

[BMR Tech]

Brian, why are you having an issue with this?

If the trans is at 0, then you would want the pinion XX degrees down. (XX=whatever you want your pinion angle)

I wish I could've been around many years ago. First, I wouldn't call it pinion angle. Second, I would've never made up adding or subtracting, negative or positives.... All that does is confuse people.

If you want -2, you drop the pinion down 2 degrees in relation to the drivetrain. What this does is, when the axle rotates, it puts the angles parallel.

The picture I made a few posts up, couldn't be any more precise. The gauge faces make sense, you must be having a brain-fart.

 

[BMR Tech]

Subbing for the discussion....bad vibration from 70-80mph. Turns on and off like a switch.

Another question...can a poorly adjusted pinion angle eat up the pinion bearing? I switched to 4:10's last year and when we removed the factory 3:55's...the pinion gear pretty much fell out of the carrier.

RH

Absopositivlutely.

This is why I urge people to get an adjustable UCA when they lower their cars.

 

[fdjizm]

Did I do good kelly!?
Skwerl, make it look like my gauges measuring from the driver side and you're all set!

 

[skwerl]

Thanks Kelly, that clarifies it for me. I just wanted to confirm that the pinion needs to point down, not up, in relation to the transmission.

After installing my new T56 trans, my pinion angle was about +4 so it was way out of whack. With the new adjustable UCA I had to shorten it almost as short as it would go to get my pinion angle to about 0. I had to confirm I was going in the right direction before shortening it up even more and possibly hitting the adjustment stops on the UCA.

 

[BMR Tech]

Brian, if you need to....you can also shim/space the transmission to help you out.

You have a 1-pc DS right? What are your angles at? Call me tomorrow if you have any questions.

 

[skwerl]

My 1 piece driveshaft is on a UPS truck heading back to Michigan due to a vibration issue. Car is on jack stands in the garage right now.

 

[fdjizm]

Ahh just thought about it, my prothane motor mounts are kind of smushed.
If I get new ones that will change the angle of my dangle right?

 

[rojizostang]

just get this and forget pinion angles

 

[fdjizm]

I think I am all set now, I will save the $800 bro thanks

 

[lindertw]

just get this and forget pinion angles

wish it were that easy... I have one of those and just installed it, -2.5deg pinion angle set and I had vibrations at ~30mph, 60mph and 100mph.

Removing it today to send it back for inspection (sounds like skwerl and I have the same luck)

 

[DiMora]

Brian, why are you having an issue with this?

If the trans is at 0, then you would want the pinion XX degrees down. (XX=whatever you want your pinion angle)

I wish I could've been around many years ago. First, I wouldn't call it pinion angle. Second, I would've never made up adding or subtracting, negative or positives.... All that does is confuse people.

If you want -2, you drop the pinion down 2 degrees in relation to the drivetrain. What this does is, when the axle rotates, it puts the angles parallel.

The picture I made a few posts up, couldn't be any more precise. The gauge faces make sense, you must be having a brain-fart.

What Kelly said.

Brian, I made you a drooring. A simple pic can be worth a thousand words...

just get this and forget pinion angles

Or, learn how to set pinion angles, and run any drive-shaft you want to. Since the T56 Magnum kits come with a shaft, that ind of ties the end-users hands, so this topic is a necessity.