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Royal Purple Max Gear 75w90 Gear Oil

Market Price $19.99 You Save 19% ($3.86)
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$16.13

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  • Item 45003
  • MPN# 1300

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    Features & Details

    • Fully Synthetic
    • Friction Modifier Included
    • Protects Against Wear
    • Reduces Gear Whine
    • 75w90 Weight
    • 8.8" Ford Rear Ends Require 3 Quarts
    • For 1979 to 2017 Mustangs
    Pure Performance. Maximize performance from your Mustang's drivetrain with Royal Purple Max Gear oil. This fully synthetic oil is the perfect complement to new gears, lubricating better and ensuring your differential keeps working its best whether it has gone a thousand miles or a hundred thousand.

    Protect Your Investment. Made with Royal Purple's innovative Synslide® additive, Max Gear oil is perfect for upgrades or routine service. It's the gear oil of choice for greater wear protection and lower temperatures for every car, from daily drivers to track-day toys. It prevents corrosion and meets all warranty requirements, so adding Royal Purple Max Gear oil is great for peace of mind when it comes to your Pony.

    Includes Friction Modifier. Unlike other oils, all viscosities of Max-Gear® are formulated with hypoid friction modifiers necessary for use in clutch or cone type differentials. No additional additives are necessary.

    Application. Royal Purple Max Gear 75w90 weight oil is recommended for use in 1979 to 2017 Mustangs and is compatible with other oils. Three (3) quarts of gear oil are required to fill a 8.8" Ford rear end.

    Fitment: 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Details

    What's in the Box
    • (1) one quart bottle
    Installation Info
    Tech Specs
    Will it fit my Mustang?
    • Boss 302 - 12, 13
    • Bullitt - 01, 08, 09
    • Cobra - 93, 94, 95, 96, 97, 98, 99, 01, 03, 04
    • Cobra R - 93, 95, 00
    • EcoBoost - 15, 16, 17, 18
    • GT - 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, 11, 12, 13, 14, 15, 16, 17, 18
    • GT350 - 15, 16, 17, 18
    • GT350R - 15, 16, 17, 18
    • GT500 - 07, 08, 09, 10, 11, 12, 13, 14
    • LX - 87, 88, 89, 90, 91, 92, 93
    • Mach 1 - 03, 04
    • Other - 79, 80, 81, 82, 83, 84, 85, 86
    • V6 - 94, 95, 96, 97, 98, 99, 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, 11, 12, 13, 14, 15, 16, 17

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    7 Questions / 6 Answers

    Ask a Question

    For 6th gen with Torsen 3.73 the owners manual list 1.5 liters and like 3 oz of friction modifier as capacity. Why are 3 quarts needed?

    DaveL

    • Hello! From my understanding it does vary slightly, but its about 2 quarts of gear oil and a bottle of friction modifier which is about 4 oz and you should be good.

      Ryan H

    Helpful (1)

    going to change my diff to a lsd with 4.10 gears, i have an 08 v6 wondering what the difference between the 75w90 75w140 gear oil which would be recommended

    marty1996

    • The differences in the Royal Purple Max Gear Gear Oil, 75w90 and 75w140 would be the viscosity of the oil throughout a temperature range. For moderate driving applications, 75w90 would be best, however, if the vehicle is driven in more extreme driving conditions, the 75w140 would be best for that application. If you are using the vehicle for a particular application, please give us a call and we would be happy to recommend a weight which would be best suitable for your application.

      AMJEFF

    Helpful (1)

    Will this bottle of solution make shifting a manual tremec (2010) 5 speed shift smoother? Does it affect the shifting in a good way?

    DaveV

    • The Royal Purple Max Gear 75w90 Gear Oil will improve shift quality, especially in colder weather. The primary benefit is reduction of friction and wear.

      Rob D

    Helpful (0)

    I'm confused, so to clarify when changing Gear oil do I need 2 or 3 quarts?

    MrFordGT

    • Three (3) quarts of gear oil are required to fill a 8.8" Ford rear end.

      AMKody

    Helpful (0)

    On the bottle and in the part description it states - Friction modifiers included, no additional additives are necessary. Is the Ford modifier really required?

    ScottG

    • If you are changing gears or even adding new gear oil, it is always a good idea to add friction modifier to help the performance of the gears.

      KevinD92

    Helpful (0)

    How good will this work for the MT82 transmissions.

    Sonny11

    • This Royal Purple Max Gear 75w90 Gear Oil is meant for your rear differential, and should NOT be used in your transmission.

      SalC7

    Helpful (0)

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    Customer Reviews (54) Write a Review

    Overall Rating 4.8

    out of 5 stars

    Installation Time:Less than 1 Hour

    Installation Cost:0-$100

    • Performance Gain 4.589744 4.6
    • Fit 4.769231 4.8



    • 5/5

      Installation Time: Less than 1 Hour

      April 15, 2018

      Gear oil

      This is a great product for the rear end upgrade. Bottles are easy to handle and are priced much better than the gear oil at my local part store

      Corey

      Year: 2001 Submodel: Bullitt

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      March 24, 2018

      2012 Mustang GT.

      Back before I traded my 12 I had changed the rear end cover and changed over to RPMax 75w90. Also changed tranny to Royal Purple. For me was my best choice. Plan to do the same with my 17 GT. No need for friction additive with this .

      ArthurB

      Year: 2018 Submodel: GT

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      January 04, 2018

      Great gear lube

      The shape of the bottle definitely helps with pouring the fluid into the rear end case. I have also noticed how quiet and seems to spin more freely than it did with the factory fluid. Highly recommend

      CJ50NA

      Year: 2012 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      October 31, 2017

      Works great

      Great product already has the friction modifier in it so it's prefect for rear gears changes only thing is you'll only need two for a 8.8 rear end where the website says it takes three

      RobertC

      Year: 1986 Submodel: Other

      Helpful (3)

    • 5/5

      Installation Time: Less than 1 Hour

      September 19, 2017

      Royal Purple

      This is the oil that came in the installation kit I bought w/ my 4:10 gears. The rear diff sounds quiet, so it must be doing it's job. Royale Purple has a good reputation and has been around for years.

      Tripe

      Year: 2004 Submodel: GT

      Helpful (1)

    • 5/5

      September 15, 2017

      2003 Mach 1

      A must when changing out the rear-end, replaced 3.55 with 4.10 WOW!

      DennisW

      Year: 2003 Submodel: Mach 1

      Helpful (2)

    • 4/5

      Installation Time: Less than 1 Hour

      September 14, 2017

      Differential fluid exchange

      Changed fluid on tear and it works good. Everything seems to be smooth. Works as advertised.

      EdwardD

      Year: 2000 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      August 25, 2017

      ROYAL PURPLE

      Its Royal Purple and it already comes with the friction modifier in the oil so you will not need to add or buy it separate.

      EdwardZ

      Year: 2007 Submodel: GT500

      Helpful (1)

    • 5/5

      Installation Time: Afternoon

      July 01, 2017

      Purple Powerrrr

      The Royal Purple price is great. The product is the best out there. It took me about 1 and half to complete. This is truly the best color out there. Thanx American Muscle for the great products you put out here.

      DavidM

      Year: 1997 Submodel: GT

      Helpful (2)

    • 5/5

      May 30, 2017

      GOOD GEAR OIL

      Needed my LSD re shimmed and added new plates since it had to come out. Used the Royal Purple on the recommendation of my mechanic who is a mustang guru. All is good, no problems and the rear runs smooth n quiet. I also added the friction modifier for full protection and maintainence.It's also peace of mind knowing there's good gear oil in the rear for years of worry free driving

      Tommy5oh

      Year: 1994 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      May 02, 2017

      Name speaks for itself

      Anyone that knows about Royal Purple knows that its some of the best stuff out there u can get.

      Keezy

      Year: 2017 Submodel: GT350

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      April 27, 2017

      Great Product!!!

      Exactly what my new gears deserve. GREAT Product!! Thanks American Muscle!!!!!

      BrandonF

      Year: 2004 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      April 10, 2017

      Best gear oil

      Been using RP gear oil for 15 or 16 years. Best gear oil and it already has the friction modifier in it. All of my vehicles are switched out with RP.

      PDP1

      Year: 2014 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      April 04, 2017

      Used on 2015 s550

      Although diff tag says to use 75w85, i went with 75w140. Smoother gear engagement was immediately noticeable. No more thuds or clunky either. Used about 2.5-2.7 quarts in total. Highly recommended for those who race car their dailys. I also run Royal purple in my motor as well as transmission.

      wolfofspring

      Year: 2015 Submodel: GT

      Helpful (2)

    • 4/5

      Installation Time: Less than 1 Hour

      March 30, 2017

      Royal purple oil gear.

      Fast .delivery !! Great price ,quality product only at Am.

      RaulV

      Year: 1997 Submodel: Cobra

      Helpful (2)

    • 5/5

      Installation Time: Afternoon

      March 12, 2017

      you can feel the difference in your differential!

      you can feel the difference in your differential! awesome...www.americanmuscle.com very good price.

      SMukherjee

      Year: 1979 Submodel: Other

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      February 25, 2017

      Quieter gears

      I haven't used this long enough to rate it but have used royal purple before and had quieter gears because of it. One question i have is why you don't send manufacture recommended weight with gears and install kit.The owners manual calls for 75-140 instead of 75-90.

      LyndaP

      Year: 2003 Submodel: GT

      Helpful (2)

    • 1/5

      November 03, 2016

      Got the wrong weight

      Said it was for an 03 Mustang, but not for mine so I just wasted some money and couldn't use them.

      Mdetore09

      Year: 2003 Submodel: GT

      Helpful (2)

    • 5/5

      Installation Time: Less than 1 Hour

      December 22, 2015

      great

      used this with the install of my 4.10 gears. best brand that i have used!

      KaitE

      Helpful (1)

    • 5/5

      Installation Time: Less than 1 Hour

      April 25, 2014

      quality royal purple product.

      I find myself buying more and more things from royal purple now a days. they make great synthetic oils that stand the test of time.

      LOUISSIUOL

      Year: 2011 Submodel: GT pa

      Helpful (1)