Eaton Detroit TrueTrac GM 8.5 Inch 10 Bolt 30 Spline Rear Differential - 913A481 |

Eaton Detroit TrueTrac GM 8.5 Inch 10 Bolt 30 Spline Rear Differential - 913A481

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  • Eaton | Part Number: EAT913A481
  • Popular Axle Manufacture:GM
  • Axle Location:Rear
  • Axle Type:GM 10 Bolt 8.6 Inches|GM 10 Bolt 8.5 Inches
  • Fitment:Universal Fit
  • Axle Spline:30 Splines
  • Differential Type:Limited Slip Assembly


The Detroit TrueTrac Limited Slip is an all gear driven clutchless differential. The TrueTrac will automatically provide smooth transfer of power from the slipping wheel to the non slipping wheel to help you out of a jam. With no clutches to wear out, you will have a dependable long lasting Limited Slip differential.

Customer Reviews

4.0 4.0
1 Customer ratings
4.0 pretty impressed

I recently replaced my factory g80 hybrid locker with a trutrac. I am really impressed by how smooth and quite it is. Theres never any question if its working right (unlike my factory g80). It does good on and light offroad. I do know that if you get one tire off the ground it wont work until you put light pressure to the brakes. But for a stock or mildly modified truck they work great.

from missouri |




Question & Answers

14 Answered questions

Q: I have a 2011 GMC Sierra, 3:42 gears. 40047269B. What install kit will i need and what will i need with it? Answer this question

A: You need these part numbers: D/S706988X and G/225-2022.

Answered by Kelly from 4WP Corporate Headquarters on 11/16/2020

Q: Hi, will this work to replace the g80 locker, 10 bolt diff, in my 2000 Z71 1500? Thanks. Answer this question

A: Hello Jon Yes this is the correct unit to replace your G80 in your Z71. Thanks

Answered by Rody on 08/15/2015

Q: I have a Z71 06/09 can I use stock bearing OE? Do I need different bearings how can I tell what the bore is? Answer this question

A: Thanks for the inquiry mike, the Detroit Locker GM 8.5in.10 Bolt 30 Spline Rear TrueTrac part # EAT913A481 for installation 2009-2013, 10 bolt use 35-2022A or 2 each TIM LM603049 AND LM603012.

Answered by RK on 08/09/2015

Q: i have a 2001 gmc sierra 1500 4x4. does this unit come with all internal parts? could i just hook up my ring gear and pinion gear and work just fine? or what other products do i need? thank you in advance- Corey Answer this question

A: Hello Corey Yes it is the complete carrier unit just bolt your ring gear on and go. You may want to buy new carrier bearings for it makes it easier to install. Thanks

Answered by Rody on 08/07/2015

Q: I have an 08 chevrolet 1/2 ton 4x4 with the 10 bolt 30 spline rear end. Drum brakes, with out active brake control and 3:73 gears. The factory carrier and internals are in pieces. I and installing 4:56 gears front and back and am looking at this unit to use in the rear with them. I am wanting to double check this unit is what I need. Also I was planning on reusing the stock axles. Is this unit compatible with my 08 chevy? Thank you. Answer this question

A: Hello Yes this is the correct unit for your 8.6 10 bolt rear axle. It is the strongest unit by far for your axle also. It will work with the 456's and your stock axles shafts just fine. Thanks Rody

Answered by Rody on 04/29/2015


The Eaton Corporation has enjoyed over a century of innovation and is in the business of powering Jeeps with a top-rate lineup of lockers, open differentials and limited slips. Traction performance is critical while jeeping and we carry Eaton components for upgrading vehicle traction. Compatible with different axle splines and various gears, these parts are often rebuildable and are top performers on and off-road. Eaton's rich tradition of engineering innovative, dependable products extends to off-road parts and accessories for 4x4s and they have evolved to become the industry standard in differentials, lockers and limited slips. Shop Eaton Now