What is the spline in my rear end? how can i find out?

[jose_bigred]

So i want to put a posi locker in my rear end. I have the 8.8 housing i think lol.. my truck is an 08 f150 4.6 2v and only pulls with one tire! sad Will adding the posi locker help with better take off at WOT??? Have a set of 4.10 gears but waiting for a posi locker to come by so i can do it alll at once! So if any one can help me i would really aprecciate it! =)

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[Tornadom]

Originally Posted by jose_bigred

So i want to put a posi locker in my rear end.
I have the 8.8 housing i think lol.. my truck is an 08 f150 4.6 2v and only pulls with one tire! sad

Will adding the posi locker help with better take off at WOT???

1). Unless it has been changed by someone, your '08 F150 4.6L has the 8.8" rear axle with 31 splines.

2). A posi and a locker are two separate things. A posi, also known as a limited slip differential will provide power to both rear wheels under most conditions, yet it still allows them to turn at different speeds to negotiate corners smoothly. A locker is a more aggressive traction aid that will provide power to both wheels under pretty much any condition, but is less forgiving on the road than a limited slip. To answer your question though, either one of these will help get the power to both rear tires. If you had problems with traction before, I would imagine a limited slip (posi) or locker either one could go a long way towards helping you.

[05RedFX4]

Originally Posted by Tornadom

1). Unless it has been changed by someone, your '08 F150 4.6L has the 8.8" rear axle with 31 splines.

2). A posi and a locker are two separate things. A posi, also known as a limited slip differential will provide power to both rear wheels under most conditions, yet it still allows them to turn at different speeds to negotiate corners smoothly. A locker is a more aggressive traction aid that will provide power to both wheels under pretty much any condition, but is less forgiving on the road than a limited slip. To answer your question though, either one of these will help get the power to both rear tires. If you had problems with traction before, I would imagine a limited slip (posi) or locker either one could go a long way towards helping you.

Absolutely correct.

The 8.8 rear axle has 31 splines, the 9.75 has 34 splines, and the front 8.8 has 28 splines.

[jose_bigred]

Ok that was a good lesson guys!!! now i need to find a posi or a locker with 31 splines!!!

Thank you both very much!

[05RedFX4]

here is a detroit truetrac for a 31 spline 8.8

http://nationaldrivetrain.com/shopsi...trac_ford.html

http://www.drivetrainspecialists.com...duct-5411.html

and the detroit locker for the 31 spl 8.8

http://nationaldrivetrain.com/shopsi...lock_ford.html

http://www.drivetrainspecialists.com...duct-1125.html

Both are a simple bolt in and neither one reqiures friction modifier like the clutch type posi units.

[4.6 Punisher]

Originally Posted by 05RedFX4

here is a detroit truetrac for a 31 spline 8.8

http://nationaldrivetrain.com/shopsi...trac_ford.html

http://www.drivetrainspecialists.com...duct-5411.html

and the detroit locker for the 31 spl 8.8

http://nationaldrivetrain.com/shopsi...lock_ford.html

http://www.drivetrainspecialists.com...duct-1125.html

Both are a simple bolt in and neither one reqiures friction modifier like the clutch type posi units.

The TrueTrac requires you to NOT use friction modifier and only conventional gear oil.