Warranting the justification for a new rearend isn’t really that hard if you’re making big power, but at what point is that upgrade necessitated? Is it when a component in the factory rearend breaks, caused by an increase in power or a stickier tire? Or, is it before any additional power is added, upgrading the rearend as a precautionary measure to that big boost in power to come?

Whichever path you decide to choose, upgrading the rearend on a solid axle car is crucial to racing your car; and our friends at Moser Engineering out of Portland, Indiana, have been the go-to folks for building virtually anything rearend related since the early ’80s. From axles, differentials and bearings, to complete rearend packages, the company provides both street and strip enthusiasts with just about every rearend solution imaginable.

Next in that line of rugged rear axle gear is the company’s latest innovation — the all-new Moser M88 rearend package. This Moser 8.8 eliminates many of the OEM 8.8 shortcomings, and it delivers the bulletproof-like performance that enthusiasts would expect from a Moser product; like the popular M9 housing, but at a more affordable price. Follow along as we dive deeper into its latest offering built specifically for the street/strip enthusiast.


In A Nutshell

Did you know that the Moser M88 rear end package can be finished in several powder coated options?

Did you know that the Moser M88 rearend package can be finished in several powdercoated options?

Moser M88 Rearend Package

  • Higher ductile-strength nodular steel construction
  • Larger 3x.025-inch-wall, seamless, DOM tubes
  • Larger main caps
  • Several differential, gear, axle, stud, finish, and brake options
  • Perfect OEM replacement for ’79-’14 Mustangs
  • Custom-built to order
  • PN 88
The short version of the Moser M88 is that this unit was designed by Moser as an improvement to the already solid Ford 8.8-inch rearend, save for some new and exclusive features, and customization, of course. For example, the M88 features a near-endless amount of customization when it comes to spec’ing your own personal rearend package.

From choosing axles, differentials and gears, to custom brakes and powercoated finishes, it’s almost guaranteed you won’t run into another person on the street or the strip with the same spec’d rearend as yours.

One of the best characteristics about the OEM 8.8-inch rear end is the endless combination of gears, axles and differentials — and Moser has incorporated that customization one step further by using the same “premium nodular steel Moser has used in the industry-leading Moser 12-Bolt and Moser 60 rearend assemblies,” according to the company.

From there, the M88 was then reinforced with additional material and webbing in the areas the previous unit lacked, such as the smaller factory axle tubing. Moser replaced it with made-in-the-USA, 3x.25-inch-wall, seamless, DOM steel tubes for strength far beyond its OEM 8.8 counterpart. Other additions such as CNC-manufactured housing ends give enthusiasts the option of retaining a C-clip or opting for a press-on, 9-inch-style oversized bearing for retention and safety.

Moser also includes an all-new set of heavy-duty, oversized main caps which help direct any and all forces exerted against the main caps back into the casting (and the performance cover) when equipped. Finally, improved oiling of bearings, as well as cooling of the gear set and carrier, help further increase life of all the M88 components.


Beyond Face Value


We basically took a very successful unit, which has sold literally tens of thousands of units worldwide through Ford, and made it that much better. — Jeff Anderson, Moser Engineering

“The M88 is a Moser Engineering-designed replacement for the factory Ford 8.8-inch rearend,” said Jeff Anderson, marketing director for Moser Engineering.

“We basically took a very successful unit, which has sold literally tens of thousands of units worldwide through Ford, and made it that much better. Ford has used this rearend as the OEM basis since as early as 1979 in the Fox Mustang platform,” Jeff explained. “The 8.8-inch was used in typically anything powered by a V8 application. Many of the original units started off as 28-spline C-clip applications, later moving to 31-spline. It’s been a very successful unit for Ford. The 8.8-inch has a low parasitic drag, which is great for fuel economy. That’s important to an OEM manufacturer, but a unit that has this size of the ring and pinion, and the application that they came in, could handle a decent amount of power.”

As time went on, Ford seemed to have moved away from that. Their product plans changed, as Jeff continued explaining. “There’s a lot of folks out there with 8.8-inch rearends; and with increased horsepower, they’ve found ways to unintentionally break these OEM rearends,” he said.

Every M88 housing comes equipped from Moser with a stronger, more durable spherical upper control arm bushing from the factory – a must for any serious street/strip application.

Every M88 housing comes equipped from Moser with a stronger, more durable spherical upper control arm bushing—a must for any serious street/strip application.

“As production has stopped with the 8.8-inch, there are no more units that you can buy brand new from the factory. The folks who have to take a trip down to the scrapyards are finding that, just like the GM 12-bolt rearends, these units are starting to disappear from the scrapyards,” Jeff explained. “There’s a big demand for these units now, and it’s definitely a mid-level product. The Moser M88 really fits between a factory Ford 8.8-inch rearend and say, something like a Ford 9-inch or an M9. Where the M88 really shines is that it’s not as heavy as other units.”

“A lot of folks don’t want to perform any permanent modifications to their vehicles, like having to cut their cars up to make room for a unit to fit,” he added.

Stronger axles equal a stronger rearend, and Moser knows the exact recipe for a bulletproof street/strip machine.

What Moser decided to do was to capitalize on the success of the GM 12-bolt and the Dana 60. They accomplished this by using its casting expertise that they’ve gained from years of experience. The company has come up with a new unit that has improved strength, thanks to many advances over the years both in casting technology, and how to cast a better nodular unit, as Jeff put it below.

“We’ve incorporated that expertise into this unit, as well as better lubrication ability, and increased webbing in the original areas where the OEM unit was lacking. We’ve also designed this unit to work with the larger 3-inch tubing. Instead of having to bore or weld a smaller tube that came with the original OEM unit, you can capitalize on a stronger, 3-inch tubing. It’s a lot stronger, and a much better material for a unit like the M88.”


Fitting In

Just like the OEM 8.8-inch unit, the M88 uses the same stock spring location.

Just like the OEM 8.8-inch unit, the M88 uses the stock spring perch locations for a direct bolt-in fit.

As Jeff went on to say, the M88 definitely has a big place in the musclecar market. With inexpensive horsepower, and what’s available today, it’s a lot easier to build a car than it once was. It’s obvious that there’s definitely a place for this unit—especially for the folks that don’t want to fully commit to cutting or modifying their car to make room for something larger like a 9-inch, the M88 is an ideal option.

“We’ve found a fantastic way to increase the factory 8.8-inch rearend,” he elaborated. “This allows it to handle a lot more power, and there’s definitely a place for this unit on many horsepower-driven applications. We’ve basically designed this for the enthusiast who is the occasional-dragstrip kind of car person. This is really where we see the failures on the OEM 8.8-inch rearends. When you put a stickier tire on the rear, and launch at a high RPM, you’re just asking for failure on a factory unit. It’s ridiculously easy to snap an axle, or even rotate the tube in the factory casting.”

As detailed previously, the M88 housing uses factory mounting locations throughout.

As detailed previously, the M88 housing uses factory mounting locations throughout.

At the end of the day, this unit is really for the folks who have stepped the power up in their application. With the increased diameter tubes, it’s definitely constructed to work better with straight-line applications. Ultimately, Jeff told us it’s designed to replace a factory or (modified factory) setup.

“It’s really for the enthusiast who knows that they’ve got a family who rides in the vehicle as well, and they can’t commit fully to a drag-only application. They have a street car, and they want to keep it that way, and that’s what we’re here to help them with,” Jeff said. “It’s part of the market; when you own a Mustang, you didn’t buy that car as a daily driver just to get you back and forth from point A to point B. There’s a lifestyle, and a passion that goes with owning a car like that,” Jeff concluded.


It’s obvious that most folks who buy Mustangs typically aren’t going to leave their cars stock, and that’s why Moser is here to support them. It’s part of being an automotive enthusiasts — we’re always looking to do some tweaks and get more power out of our cars. Before you know it, you’ve stepped the power up to more than what the factory unit can handle. And, of course, no one wants to go backwards — so you replace the unit in the car with something like the M88, before it breaks.

If the M88 sounds like the solution you’ve been looking for, head over to Moser Engineering‘s website for more information on this robust rear.