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Royal Purple Max Gear 75w90 Gear Oil

35 Reviews
Our Price

$19.99

  • Item #45003
  • MPN# 1300

  • Market Price $24.99
  • You Save 20% ($5.00)
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Features
  • Fully synthetic
  • Friction modifier included
  • Protects against wear
  • Reduces gear whine
  • 75w90 Weight
  • 8.8" Ford rear ends require 3 quarts
  • For 1979 to 2014 Mustangs
Description
Pure Performance. Maximize performance from your Mustang's drivetrain with Royal Purple Max Gear oil. This fully synthetic oil is the perfect compliment 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 2014 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 Details

Won't fit? Add an exception

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

Most Helpful Reviews

5/5
it works like Jesus, 05 Mustang GT

The shop that installed my 4.10 Gears gave me a skeptical look when I told them to use this stuff instead of their regular oil, he made it seem like it doesn't make a difference. But on the same conversation ...

Read More
Helpful (6)

5/5
Good stuff

Works as it should. Fluid is not as viscous as I had imagined and this is good because clean up was easy. Took about 2 bottles to fill up my 7.5'' differential (98 V6).I recommend you use "Right Stuff" ...

Read More
Helpful (3)

Read All 35 Reviews
Overall Rating 4.9 out of 5 stars

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2 Questions / 2 Answers

Ask a Question

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?

dan06v6 Year: 2006 Model: V6

  • yes will need 3 the differance in size does not reduce capacity by one quart

    blueblood04 Year: 2004 Model: Mach 1 Top 25 Contributor

    Good Answer (0)

Show 1 more answer

How good will this work for the MT82 transmissions.

Sonny11 Year: 2011 Model: V6

Answer This Question I need this answered (0) (0)

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Customer Reviews (35) Write a Review

Overall Rating 4.9

out of 5 stars

Installation Time:Less than 1 Hour

Installation Cost:0-$100

  • Performance Gain 4.4 4.4
  • Fit 4.75 4.8
  • Bang For Your Buck 4.6 4.6



  • 5/5

    January 09, 2010

    it works like Jesus, 05 Mustang GT

    The shop that installed my 4.10 Gears gave me a skeptical look when I told them to use this stuff instead of their regular oil, he made it seem like it doesn't make a difference. But on the same conversation he was warning me he has installed hundreds of rear gears on mustangs and most of them have a weird hum that has been rectified with the newer Mustangs, so he warned me some people don't like it. When I got my car back there was no humming or any of the other issues he warned me about, so like Jesus, if you believe it works then it works.

    R. Hidalgo

    Year: 2005 Model: GT

    Helpful (6) (0)

  • 3/5

    Installation Time: Afternoon

    October 02, 2011

    Good product but 75w-90 wrong for 2002 Mustangs with 8.8 rear end

    Purchased 75w-90 based on American Muscle web page stating it was the correct fluid. Order was on the way before I checked owner's manual. Ford specs 75w-140 for the 02 Stang and the data tag on the differential cover says "Use only 75w-140". Called American Muscle they said the 90 weight would be OK. Could have chanced it, but was able to exchange the 90 for 140 weight at a local retailer at no cost. Put in the specified 75w-140 and all is good. Be aware that you need to drop the sway bar to reinstall the cover without making a mess of silicone gasket sealant. Royal Purple products are great

    Rix02

    Year: 2002 Model: GT Driving Style: Daily Driver 'Stangs I have owned: 3 North Salt Lake, UT

    Helpful (3) (0)

  • 5/5

    August 24, 2010

    Good stuff

    Works as it should. Fluid is not as viscous as I had imagined and this is good because clean up was easy. Took about 2 bottles to fill up my 7.5'' differential (98 V6).I recommend you use "Right Stuff" gasket maker for sealing the differential cover.

    Manuel

    Year: 1998 Model: V6 Driving Style: Daily Driver

    Helpful (3) (0)

  • 5/5

    August 08, 2011

    Smooth running!

    I just changed the diff fluid today. I did it at the same time as the tranny fluid. I dont have any scientific results but I can say there is minimal resistance in the drive train. I run all royal purple and I feel confident that wont have any fluid related problems. I changed it at 70k and the old fluid seemed like it would be good till 100k. I saw 3 different numbers from diff fluid intervals so I went with the shortest one.

    Jared

    Year: 2006 Model: GT Driving Style: Street / Strip

    Helpful (2) (0)

  • 5/5

    May 11, 2010

    *****

    GREAT STUFF. I DO ALOT OF HAULING AND HAD CHATTER IN THE REAR CLUTCH PACKS.. NOT ANY MORE.

    DAVE W

    Helpful (2) (0)

  • 5/5

    April 22, 2010

    Good stuff

    I love how this stuff come with friction modifier already, less stuff to hassle with. Just did a girdle install and use the Max Gear RP oil and have no complaints. I have liked all the RP stuff I have used in the past as well.

    Will

    Helpful (2) (0)

  • 5/5

    April 16, 2010

    Good Stuff

    I was looking for this gear oil at my local auto motive shops and they where all asking this really crazy prices for this stuff. I usually make some purchases through American Muscle.com but never thought they carried gear oil. When I checked I was amazed at the price. I recently had 3.73 gears put on my car with the Royal Purple Gear Oil and could not be happier.

    Art Torres

    Helpful (2) (0)

  • 5/5

    June 10, 2010

    works

    eliminated the 2nd to 3rd synchro crunch in my six speed miata. Shifts like butter now

    Mark

    Helpful (2) (1)

  • 5/5

    April 24, 2010

    nice stuff

    works well ,no chatter around turns

    nick z

    Helpful (1) (0)

  • 5/5

    Installation Time: Afternoon

    March 07, 2012

    Rotal Purple Rocks!

    Took me a little while to do the rear diff oil change, it was my first time though but it feels amazing! 100% recommended

    Top 1000 Contributor

    DiegoRL

    Year: 2003 Model: GT Driving Style: Daily Driver 'Stangs I have owned: 2 Brownsville, TX

    Helpful (1) (1)