Hey, guys.
Stephanie with AmericanMuscle.com here with this Yukon Gear DuraGrip Posi rear diff for
28 spline 7.5 rears, or to break it down, '79 to'85 V8s and '86 to 2010 V6 Mustangs.
This Posi unit from Yukon Gear is going to be a good option for the guys out there with
a seven-five rear that are looking to replace their diff with an upgraded one that is a
stronger, true Posi unit.
This diff has composite discs and requires the use of 28 spline axles, which means that
you don't have to upgrade over the factory units.
This diff will get your car away from one wheel burnouts and give you a solid upgrade
that's going to hold up better to more aggressive driving.
There are a couple of reasons to change or upgrade your differential.
The first one is to move to a true Posi unit, so you have a consistent dual wheel spin instead
of a single wheel spin.
Another thing to consider is maybe you've got a stock diff and it's just getting old
and chattering, or maybe you plan on hitting the drag strip and you've got some power that
you'd like to cleanly get to the ground.
But no matter what your reason is, this Yukon Gear diff is upgraded and it's slightly beefed
up, and it's a quick solution to help you get power to the pavement through a true LSD
setup.
If we take a step back for a minute, the point of a limited slip differential, or LSD like
this one here, is to allow both rear wheels to put power to the ground and get better
traction to both rear wheels.
So the thought is, if there's any type of open diff transfer or uneven transfer of power
and torque to one particular wheel over the other that'll create a useless wheel spin
where the car loses it's forward momentum, the LSD is designed to eliminate that spin.
It'll transfer the torque of both rear wheels evenly, which will have a few benefits in
both street and track applications.
This means a stable differential lock pattern that won't fail due to the upgraded components,
no slipping, more durability, gentle transitions and even a quiet operation.
I'm saying that this diff is a heavy duty diff because of features like the nodular
case.
The case is constructed from nodular iron, but more importantly, this diff also has forged
4320 steel internals and composite clutches.
These are upgraded items that mean the diff will be dependable under aggressive driving,
and in more of a heavy duty performance life.
This also means a longer life span.
The composite discs that I'm talking about here are the discs that are in the clutch
pack, and the clutch pack is what activates the LSD.
And more specifically, the clutch plates create the locking performance of the LSD that I
spoke about earlier, so it's important that they will hold up to the spinning [SP] end.
Like I mentioned earlier, this diff is going to require the use of 28 spline axles, which
is the spline count that the 7.5 rear comes from the factory with, so you aren't looking
at having to upgrade your axles with this diff, which is nice.
It's one less expense that you'll be facing when you're ready to move up to a diff like
this.
This is going to work for cars with a solid axle setup, and you'll need to reuse or grab
a new seven-five rear gear set.
This does not come with new aftermarket rear gears.
One other note would be the recommended use of 75W90 rear gear oil, since this'll give
you the same oil weight as factory, and you're going to need three quarts of that and four
quarts of friction modifier for the initial fill.
When it comes to price, this rear diff is going to cost just over $400.
It's actually one of the only two rear diffs for the seven-five rear that are currently
available on this site, and it's a little more wallet-friendly of the two options.
There is always the other option of upgrading to an eight-eight rear and 31 spline axles
if you have the torque and power to justify that, but that's most likely going to be a
little bit more expensive depending on which setup you choose to go with, and considering
the other items that you'll need to make the switch complete.
As far as the install, you're going to need some experience with this one.
You need a few different wrenches and sockets, but an impact gun is going to help you speed
things up here, even though you can do this install with all manual tools if you wish.
A lift would also really help and you're going to need a torque wrench to do this properly.
Another thing to consider here are proper tools like a dial indicator, bearing pullers
and press, pinion nut socket, ring gear bolt socket and items along those lines just to
avoid any part damage.
You're looking at about four hours time and a three out of three wrenches on the difficulty
meter.
Going over a general install, you're going to need to get to the diff itself, so this
means pulling the rear wheels, dropping the rear brake assemblies, and draining and removing
the rear diff and cover, so you'll need something to drain into.
The axles will need to be pulled out of the diff, and the diff will need to be removed.
The shims that are on each side of the diff bearings will need to be installed the exact
same way, so keep track of those.
You're looking at some diff assembly adjustments, such as pinion depth, pinion bearing preload,
backlash and carrier bearing preload, and also some seal prep.
Then you'll have a pinion trial assembly, an initial carrier assembly, followed by adjusting
the backlash.
And backlash is the amount of ring gear that can rotate forward and backwards when the
pinion gear cannot move.
Now this is obviously a quick overview of the install, but I wanted to give you guys
an idea of what it would take so you can make a decision as to if you wish to install this
for yourself or take it to a shop.
Wrapping things up here, Yukon Gear Posi rear diff is a seven-five rear diff that gives
you an LSD setup with composite discs that's going to use with 28 spline axles.
It's an upgrade over the factory diff, and this diff is a good option for those looking
for a maintenance replacement or those looking for something to make sure that you can get
some extra torque planted squarely to the ground.
And you can check it out some more right here at AmericanMuscle.com.