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Royal Purple Max Gear 75w90 Gear Oil

$0.00
Market Price $19.99 You Save 19% ($3.86)
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$16.13

FREE Shipping on orders over $49

  • Item 45003

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    Features, Video & 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

    Review & Installation Video

    Review & Install Video

    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 2019 2020 Details

    MPN# 1300

    CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

    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, 19, 20
    • Cobra - 93, 94, 95, 96, 97, 98, 99, 01, 03, 04
    • Cobra R - 93, 95, 00
    • EcoBoost - 15, 16, 17, 18, 19, 20
    • 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, 19, 20
    • GT350 - 15, 16, 17, 18, 19, 20
    • GT350R - 15, 16, 17, 18, 19, 20
    • GT500 - 07, 08, 09, 10, 11, 12, 13, 14, 20
    • 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

        Questions & Answers (11)

        5 Top Rated Questions

        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

        • 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.

        Helpful (2)

        One of your staff's comments says to use the friction modifier with Royal Purple. But Royal Purple says the friction modifier is in it already and is not needed. So what is the correct answer ?

        • Even though the Royal Purple gear oil does include some friction modifier, we still recommend using the ford friction modifier for better performance but you can definitely just use the Royal Purple gear oil alone. 

        Helpful (1)

        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?

        • 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.

        Helpful (1)

        Will this work on a 2014 rear differential to help stop some rubbing noise? Also how much is needed

        Which is the recommended oil for daily driving and no track or drag use, 75w90 or 85w140? What weight is the factory fill?

        • It depends on the year and model Mustang you have, you should have your answer in your owners manual or by contacting and speaking with your dealership directly.

        Helpful (0)
        Post Your Question
        6 More Questions
        I ordered and received my order of 1 qt., not realizing it was only a qt. bottle. When I checked the quantity needed I saw it required 4.25 pints, but the manual also say 75W-140. Your site said this was the correct lube for the car when I ordered it. What do you recommend? 2008 Mustang GT/CS 0 answer
        Will this bottle of solution make shifting a manual tremec (2010) 5 speed shift smoother? Does it affect the shifting in a good way? 1 answer
        I'm confused, so to clarify when changing Gear oil do I need 2 or 3 quarts? 1 answer
        On the bottle and in the part description it states - Friction modifiers included, no additional additives are necessary. Is the Ford modifier really required? 1 answer
        How good will this work for the MT82 transmissions. 1 answer
        7.5? 3 quarts are needed for the 8.8 but what about us v6ers. i'd get three to be safe but if i could save an extra 17 bucks that would be nice too. what do you think? 2 answers

          Customer Reviews (75) Write a Review

          Overall Rating 4.9

          out of 5 stars

          Installation Time:Less than 1 Hour

          Installation Cost:0-$100

          • Performance Gain 4.625 4.6
          • Fit 4.842105 4.8



          • 5/5

            Installation Time: Less than 1 Hour

            August 12, 2019

            Gear oil

            Worked great whent to ace to get plastic tuneing to help put it in the diff. Works great.

            Santo

            Year: 2003 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            August 11, 2019

            Better than conventional oil

            Royal Purple Max Gear Oil reduces drivetrain power loss to the rear wheels by reducing friction and heat compared to conventional oils. You can feel the difference!

            BanzaiBullitt

            Year: 1986 Submodel: Other

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            July 24, 2019

            Royal purple gear lube

            Great lubricant. My choice for any car or truck. I've used it in several mustangs now.

            BlackVertohio

            Year: 1989 Submodel: GT

            Helpful (0)

          • 5/5

            July 22, 2019

            Royal purple max gear oil

            The best oil on the market.worked great in my mustang rear end

            mustang90

            Year: 1990 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            July 09, 2019

            Great product

            Its gear oil I dont think there is much else to say.

            ChristopherS

            Year: 2007 Submodel: GT

            Helpful (0)

          • 4/5

            Installation Time: Less than 1 Hour

            July 07, 2019

            Max Gear

            Put this in my transmission, helped it out. Will likely use again.

            2BAD4U

            Year: 1995 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            June 12, 2019

            Royal purple

            Excellent product. Used in my transmission for easier shifting and in rear end for protection and quiet.

            Gj6808

            Year: 1993 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            May 12, 2019

            Good Oil

            This is a top graded lubricant that I would recommend using

            Aaronthebaron

            Year: 1992 Submodel: LX

            Helpful (0)

          • 5/5

            Installation Time: Afternoon

            May 11, 2019

            Best price

            Best gear oil on the market. No noise from the rear end after using this stuff, and i added a little bit of friction modifier just to be safe. AM also had the best price including my local stores.

            AnthonyT

            Year: 1989 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            April 18, 2019

            Royal Purple

            Use it in all my vehicle's my stang my f250 and my f150

            PhillipD

            Year: 2004 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            April 11, 2019

            Great Oil!

            I noticed a 15 degree drop in my rear end temps on the track when I switched to Royal Purple. That's a no brainer!

            Vikingnene

            Year: 2016 Submodel: GT350

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            March 23, 2019

            I love Royal Purple

            I love this product so much, I use RP for my oil and anything I can use it for on my mustang,Great product.

            Swoopty5525

            Year: 2007 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            March 18, 2019

            Royal Purple is quality you can trust

            If you race or just want your gears to last then use Royale purple gear lube. Quality at its best.

            MichaelP

            Year: 2013 Submodel: GT

            Helpful (0)

          • 5/5

            Installation Time: Less than 1 Hour

            November 26, 2018

            75W90

            HAD A NOISE IN THE REAR, INSTALLED THIS AND NOISE HAS DIMINISHED.. CANT TELL U THE PERFORMANCE GAIN.. MORE OF A FEEL GOOD THING I RECKON

            RobertA

            Year: 2014 Submodel: V6

            Helpful (1)

          • 5/5

            November 03, 2018

            Best stuff

            Going in tomorrow It's gear oil change time and transmission fluid change time...

            SpikerS

            Year: 2016 Submodel: V6

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            October 29, 2018

            Best gear oil

            This is by far the best gear oil on the market. Also cheaper than going to local parts store.

            BrianA

            Year: 1999 Submodel: Cobra

            Helpful (2)

          • 4/5

            October 22, 2018

            Maintenance

            It was time to change the diff fluid - I went with Royal Purple mainly due to other reviews. Install was easy. I have not noticed any performance increase, etc. But I feel pretty comfortable with the reputation.

            RandalM

            Year: 2006 Submodel: GT

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            October 04, 2018

            Good Stuff

            I recently replaced the rear wheel bearings in my 98 Mustang GT and had to drain and refill the diff. oil. Royal Purple Max gear oil was my choice. Not having a lift, I had to do this chore on jack stands while lying on my back. I clamped a piece of tubing to the nozzle and put the other end of the tubing into the fill hole. The stuff is thick so, it took a while and when the bottles were 2/3 empty, I poked a hole in the bottom so the rest would drain out quicker. So far, the stuff has been great.

            73challenger503

            Year: 1998 Submodel: GT

            Helpful (2)

          • 5/5

            Installation Time: Less than 1 Hour

            September 04, 2018

            Yep

            It definitely oils the gears in your car works like a charm

            carlscavuzzo

            Year: 2002 Submodel: GT

            Helpful (2)

          • 5/5

            Installation Time: Shop Install

            Installation Cost: 0-$100

            June 20, 2018

            The Best Gear Oil

            This is really great gear oil.I think it is the best for your STANG ‘S rear Rick

            Rick

            Year: 2011 Submodel: GT

            Helpful (3)