East87

I'm sitting here contemplating a gear swap (4.10's) and weighing the potential problems ($$$) versus the sweetness of steeper gears when a possible issue dawned on me.

Does pinion angle affect the installation and performance of rear-end gears at all? In other words, I am lowered in the back with Roush rears, and my pinion angle is now different than stock. Will this change in pinion angle adversely affect the gears in any way (aka whine), and will a speed shop be able to adjust the gears during install to compensate for the change in the pinion angle?

Or am I completely off base, and are the two completely independent of one another?

avengence

Wont cause a problem. You dont adjust the pinion gear inside of the diff for pinion angle. The pinion gear is stationary in the rear end, its the rear end that moves.

In other words you wont have any problems with the gear swap. I have 4.10s in my car and eibach pro kit lowering springs with no adjustable control arms of any kind.

Let me know if you have any more questions.

Stkjock

gears will have no effect

07 GT E UPP

+ 1 I Agree with avengence here in that you won't have any problems with the 4:10 gear install...
However just for your info, It's a whole different matter with Pinion angle when you put on a 1 piece aluminum DS and you are lowered

East87

Thanks you guys for the info. I'm still learning

So with 4.10's and possibly slicks...will I get into trouble with the stock DS when I hook at the track?

Stkjock

not at your power levels

One Bad Stang

As far as breaking stuff with slicks, anything is possible. But installing 4:10's creates less stress on the rest of the drivetrain. By installing a higher gear, it provides a mechanical advantage (or increases advantage) meaning its easier for the engine/trans/driveline to turn the rear tires. But keep in mind the stress is increased to the axle shafts. But we s197 folks are lucky, we have 31 spline axles from the factory.