Eaton Detroit TrueTrac Dana 30 27 Spline 3.73 Up Front Differential - 912A585

universal fit logo


  • Eaton | Part Number: EAT912A585
  • Popular Axle Manufacture:Dana
  • Axle Location:Front
  • Fitment:Universal Fit
  • Axle Type:Dana 30 TJ|Dana 30 JK|Dana 30 Standard|Dana 30 Reverse
  • Axle Spline:27 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

4.6 4.6
8 Customer ratings
5.0 This with a rear e-locker works perfectly.

Transparent until you need it. I can’t think of anything to complain about.

from Hasselt, Belgium |
5.0 Eaton Tru Trac

Works great in my TJ smooth no clicking or chattering

5.0 great value

im restoring my jeep comanche adding 456 gears to Detroit locker with 30 spline axles ,now adding the tru trac to the front

from frankton in |
4.0 Easy install, quiet operation

the tru trac installation gave my jeep some extra off road grip for weekend jaunts without sacrificing drivability on the road

from Winchester Va. |
5.0 Dana 30 truetrac

Great option for the front for the weekend warrior that doesn't need or want a locker. works great almost unnoticeable until you need it,and at half the price of a locker

from mass |
3.0 Works for light off roading

Works well for light wheeling wish I would of went with full Detroit locker.

from colorado springs colorado |
5.0 "I would buy this product again and agai


from VEGA BAJA, PR |


Question & Answers

24 Answered questions

Q: will this work for the front of 2002 s10 Answer this question

A: I'd suggest contacting eaton, I think you have a transaxle setup? Not sure what they'd offer for that?

Answered by Gerry from Stanwood wa on 11/20/2020

A: We need a little more info about your setup to get you the correct parts. Please call our sales line Toll Free: 1-877-474-4821

Answered by Kelly from 4WP Corporate Headquarters on 11/18/2020

Q: Will this fit a dana 30 out of a 2000 Jeep Cherokee Sport? Answer this question

A: You need to know the axle ratio. I ordered for the 3.73 and up. That did not work, so I returned it and ordered the 3.54 and down. Look for a tag on your diff cover. Mine stated 3.55, so the 3.54 worked.

Answered by Ruger from Denver on 03/02/2022

Q: Will this work in a 2002 ZR2 Blazer? Its a manual so it has the iron front diff housing instead of aluminum. Would prefer an E-Locker but having trouble finding one, or solid info on what will fit. Answer this question

A: The EAT912A585 fits a Jeep or Scout Dana 30 straight axle front end. It will not fit the 2002 ZR2 Blazer IFS front end. I do not have a traction device for the 2002 ZR2 Blazer

Answered by Kelly from 4WP Corporate Headquarters on 06/21/2021

Q: Would this work on a 2012 Ford Expedition? Looking for both front and rear. Thanks! Answer this question

A: The EAT912A585 fits a Dana 30 for a 3.73 and numerically higher gear ratio. The 2012 Ford Expedition has a 8.8” high pinion front end with 31 spline axles. 4Wheelparts offers the following traction devices for this front diff: ARBRD81 Air Locker, EAT19605-010 clutch type limited slip, YKGYDGF8.8-31-1 clutch type Limited slip. The rear end could be a 10 bolt Ford 8.8 or a 12 bolt 9.75. For the 8.8” 31 spline IRS differential a Eaton 913A561 Trutrac would be an excellent choice. If you have the 12 bolt IRS differential then a EAT913A477 Trutrac would be an excellent choice.

Answered by Kelly from 4WP Corporate Headquarters on 06/04/2021

Q: Will this work in the aluminum D30A used in the Jeep KJ ('05) Answer this question

A: Yes it will

Answered by Kelly from 4WP Corporate Headquarters on 12/16/2020


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


Sign up to receive deals by email!

Sign up to receive deals by text!

Please Enter valid number

By submitting, you agree to receive recurring autodialed marketing text msgs (e.g. cart reminders) to the mobile number used at opt-in from 4 Wheel Parts (4WP) on 21208. Consent is not a condition of purchase. Msg frequency may vary. Msg & data rates may apply. Reply HELP for help and STOP to cancel. See Terms and Conditions & Privacy Policy