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USA Standard Gear

USA Standard Gear SL GM12-30 GM 12 Bolt differential-30 Spline axles Spartan Locker

    • Based on 1,326 reviews
Condition: New
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$293.25 Why this price?
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Availability: Only 3 left in stock, order soon!
Fulfilled by Drivetrain America
Arrives May 19 – May 22
Order within 13 minutes
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Style: GM 12 Bolt Differential-30 Spline Count (SL GM12-30)


Features

  • Easy, drop-in installation
  • Made from 9310 steel
  • Heat treated and precision cut teeth
  • Backed by 1 year warranty
  • Fits GM 12 Bolt Passenger Car or Truck - 30 Spline Axles

Description

The Spartan Locker from USA Standard Gear is the perfect blend of affordability and performance. Designed for off-road usage, this lunchbox locker is easy to install and provides a significant increase in strength over stock differentials. Drop a Spartan in your Jeep or 4x4 today, and take to the trail with confidence! This model includes heavy-duty cross pin shaft.


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 12 x 13 x 3 inches; 0.01 Ounces


Item model number ‏ : ‎ SL GM12-30


Date First Available ‏ : ‎ February 6, 2013


Manufacturer ‏ : ‎ USA Standard Gear


Best Sellers Rank: #8,749 in Automotive (See Top 100 in Automotive) #5 in Automotive Replacement Differential Assembly Kits


#5 in Automotive Replacement Differential Assembly Kits:


Customer Reviews: 4.7 out of 5 stars 1,326 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: May 19 – May 22

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Similar Products

Top Amazon Reviews

    • Perfect Fit, Easy to install UPDATED 12/19/2019
Style: Dana 30 Differential 27 Spline Count (SL...
I installed it into a Dana 30 HP for my 99 XJ. Really easy to install, it took a couple of hours. Perfect fit, follow the instructions to the dot and you will be pleased. For my application, it is really quite, I can barely hear it while turning. BE AWARE, it might lock and unlock (in 2WD) the first 10 miles. I drove my Jeep to a parking lot and drove in circles forward and backward for a few minutes to help lubrication and to brake-in the locker. Then I drive around town for 20 min. Finally, I took it to a fire road to see how the locker works, I put it in 4 low works like a dream. It is a day and night difference. Ever since I have driven the jeep on the freeway for over 200 miles (commuting) and that has helped with lubrication. Now the locker is even quieter. I am planning on replacing the diff fluid in a few more hundred miles to remove any potential debrief from the brake-in process.. Instructions don't say anything about it but I figure gear oil is cheaper so why not. I should be going to Moab and other off-road trails in the following months, I will give an update on how it holds. UPDATE 10/23/2019 - I have run it for about 1000 miles, I have got really quire, even when I am at full lock turning in parking lots. I run Valvoline 80w-90. I have taken it off-road (Moderate trails) and it has performed great. Something that I have noticed is that right after using it on the trails, I would go back into 2WD and it gets way noisy!!!! but after driving for 20 miles it goes back to quite mode!! Loving it! IT WOULD LOCK AND UNLOCK once in a while when backing up and turning, but you can feel it in the steering wheel, it makes a loud pop noise, but if you were the one installing it you won't freak out, you would be able to tell "bad breaking noyses" from the locker loading and unloading lol 11/21/2019 Took it to rattlesnake trail (moderate to difficult) in Utah. I performed great. I was able to struggle less than my buddies with larger tires and open differentials. I have put around 3k miles on it. The more I drive it the quieter it gets. Now I can only hear it sometimes when turning full-lock on parking lots. It stopped locking-unlocking on his own while driving in 2WD on parking lots and tight places. I will keep you all posted. 12/19/2019 I have driven it for 4k miles now. I went to Moab last weekend. Wheeling on slick rock was like driving on pavement sometimes. The Locker would bind and lock and unlock pretty hard. So I had to take my turns pretty easy and some times I would cost in neutral. (I have a 5 speed). I still love it, I got me over obstacles way smoother than my buddies with bigger tires. I was able to take the hard lines on trail w/o major issues. The locker has gone quieter after many miles. I can hardly hear it while turning in parking lots. ... show more
Reviewed in the United States on September 10, 2019 by Analy
    • Barely lasted past the warranty expiring
Style: Model 35 Differential 27 Spline Count &a...
Review Image by Brian Carlson Brian Carlson
I am extremely disappointed at the quality of this product, as well as the willingness of the reseller to offer any type of remedy. I installed this in a bone stock 2001 Jeep XJ with 235/75 R15 Goodyear Wrangler tires and it lasted 18 months. The reason I took it out was the rear-end was binding up and when it released it banged hard enough to rattle the truck. Upon removing the locker (thankfully I saved the spider gear set) I examined all the teeth on the 4 locker parts. As you can see, the teeth began to gall on only ONE of the drivers. This appears to be a problem with the hardening of this particular part. The locker is now useless to me, at the price these are getting I would have expected it to last longer. Who knows how long it might have lasted on a non-stock Jeep with larger tires and having been abused on the trail. I have reached out to Amazon who referred me to the reseller who told me sorry the warranty is up...by 6 months. ... show more
Reviewed in the United States on April 29, 2019 by Brian Carlson Brian Carlson
    • Budget locker bang for your buck
Style: Dana 30 Differential 27 Spline Count (SL...
If you decide to go this route it’s a budget locker it works well install is about 3-4 hrs taking your time . Driving with it takes some getting use to but others may have different affects It will magnify any loose steering you have also check all ujoints on axle shafts And make sure to take up to freeway speeds drive to insure you did correctly Also make sure to change your diff fluid after couple hundred miles you’ll see so brass shaving in oil so don’t freak out Take corners easy don’t go full lock steer other than that it is pretty dang good First week was very nosiy after that the locker quited down and I barley here it ratcheting ... show more
Reviewed in the United States on January 29, 2018 by Casey Espeseth
    • Locked and ready
Style: Dana 30 Differential 27 Spline Count (SL...
Review Image by hi hi
Review Image by hi hi
USA standard gear's Spartan locker is the first locker I've ever driven and this was the first time I ever took an axle apart. Took me a couple hours to get everything disassembled but what a simple install. No more spider gears crawling through my diff, now I can show off on the trail and stall more, lockers take some getting used to but they're an incredible off-road upgrade especially for the price. I'm driving a 95 Jeep Wrangler lifted 4" with 33s converted to a tj style front axle shaft and I don't notice my spartan locker at all while driving in 2wd unless I move the wheel left to right while stationary. It's a locker, and so far it works great. ... show more
Reviewed in the United States on July 1, 2017 by hi hi
    • Good but instructions are crap
Style: Chrysler 8.25 Differential 29 Spline Cou...
Like everyone says, the instructions are garbage. This is how it stacks up: (Drivers side) outer spider gear, c-clip for axle, bushing, inner spider gear. Then Passenger side, same as drivers but leave out the c clip. After you get the spider gears and bushing in, insert the center pin. Then rotate the locker until you see the cutout between the spider gears. Insert the passenger c-clip here. Will take some doing because the axle has to be worked in and out until the spline cutout for the clip lines up with the opening. Make sure there is loctite on your center pin bolt. **This writeup is for information purposes only. I do not accept any responsibility for what you do with this part or how it is installed in your vehicle** ... show more
Reviewed in the United States on May 24, 2018 by Robert Anderson

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