(approx) 1 Hour
Simple installation for anyone.
- Customer Submitted:
- How to Install Gear Oil in your 1979-2014 Mustang
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ROYAL PURPLE MAX 75w140 GEAR OIL IS A GOOD CHOICE FOR ANY MUSTANG OWNER WHO’S PICKING UP A NEAR SET OF REAR GEARS AND WANTS TO MAKE SURE THEY’RE PICKING UP A REPUTABLE, RELIABLE LUBRICATION. ONE QUART HERE RUNS AT JUST UNDER THE $20 MARK, AND THE APPLYING NEW GEAR OIL GETS ABOUT A 2 OUT OF 3 WRENCHES ON OUR DIFFICULTY METER.THERE ARE SOME FACTORS THAT COME INTO PLAY WHEN PICKING OUT YOUR NEW GEAR OIL. BUT IN ORDER TO CHOOSE THE RIGHT OIL, YOU’LL FIRST NEED TO UNDERSTAND THEIR GRADES BECAUSE IT’S CRUTIAL IN MAKIG SURE YOUR GEARS MESH AND TURN SMOOTHLY WITH PROPER LUBRICATION. THIS ONE HERE IS GRADED AT 75W140. THE GRADING SYSTEM IS MEASURING THE VISCOCITY OF THE OIL, WHICH IS A MEASURMENT OF THE THICKNESS OF A LIQUID. THE LARGER THE NUMBER, THE MORE VISCOUS, OR THICK THE OIL IS. YOU’D WANT A THICKER OIL IF YOU’RE CAR IS UNDER HEAVY WEIGHT OR LOAD, OR IF YOU’VE GOT A HEAVY FOOT AND REALLY BEAT ON IT. WHEN YOU UPGRADE GEARS, MOST OWNERS WOULD UPGRADE TO A THICKER GEAR OIL TO SOMETHING LIKE THIS 75W140, ALTHOUGH IT MAY VARY DEPENDING ON YOUR NEW GEAR MANUFACTURERS RECOMMENDATIONS, AND WHAT WOULD BE BEST FOR YOUR APPLICATION.THIS GEAR OIL FROM ROYAL PURAL IS A MULTI-GRADE, SINCE YOU’RE SEEING TWO NUMBERS THERE. THE 75W BEING THE FIRST, AND 140 THE SECOND GRADE. THE W AFTER 75 REFERS TO IT’S WINTER VISCOSITY RATING, MEANING IT’S CERTIFIED AND TESTED AT 32 DEGREES FAHRENHEIT. THE 140, WITHOUT THE W, REFERS TO IT’S HEAT RATING WITH A CERTIFIED TESTING AT 212 DEGREES. A MULTI-GRADE OIL LIKE THIS DOESN’T NEED TO BE CHANGED OUT FOR THE DIFFERENT CLIMATES IT MAY BE EXPOSED TO. IF YOU’RE LOOKING FOR THE MORE VISCOUS OIL LIKE THIS ONE HERE, IT COMES AT ABOUT $20 A QUART. YOU’LL WANT TO BE SURE TO LEARN HOW MANY QUARTS YOUR MUSTANG NEEDS, AS IT CAN DIFFER DEPENDING ON GEN AND PACKAGE.ANYTIME YOU’RE CHANGING GEARS, YOU’LL NEED NEW GEAR OIL. SO THE INSTALLATION IS PRETTY INVOLVED. APPLYING THE GEAR OIL ITSELF ISN’T HARD, BUT IT REALLY DEPENDS ON YOUR METHOD. IF YOU’RE NOT ACTUALLY CHANGING GEARS, BUT JUST NEED TO CHANGE OUT THE OIL, YOU CAN PICK UP AN GEAR OIL PUMP AND TUBING IN SOME CASES. EVEN WITH THAT IN MIND, THIS METHOD GET MORE OF A 1 OUT OF 3 WRENCHES ON OUR DIFFICULTY METER. HOWEVER, IF YOU’RE COMPLETELY CHANGING GEARS, THAT PROCESS IS A FULL 3 OUT OF 3 WRENCHES ON THE DIFFICULTY METER BECAUSE YOU’RE COMPLETELY DISASSEMBLING THE DIFFERENTIAL WHEN APPLING THE NEW OIL. WITH THAT SAID, INSTALL TIMES CAN VARY FROM 1 HOUR TO SEVERAL.THAT WRAPS THIS UP SO IF YOU’RE IN NEED OF NEW GEAR OIL AND YOU’RE LEANING ON THE SIDE OF A MORE VISOUS OR THICKER OIL, THE 75W140 ROYAL PURPLE MAX GEAR OIL CAN BE FOUND RIGHT HERE AT AMERICANMUSCLE.COM.
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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
Royal Purple 01301
CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
(approx) 1 Hour
Simple installation for anyone.
What's in the Box
April 24, 2020
Built an 8.8 with stud girdle, strange spool, 410 gear, and strange race axles.Helpful (3)
January 30, 2020
They got it to me fast the best gear oil I like this company they are greatHelpful (3)
September 02, 2019
Seems to work
I assume this product is working well within my rear end as I just had the gears changed. Technically I wouldn't know unless I inspected the rear end after a few years. What I do know is that everyone knows, recognizes, and uses Royal Purple or just purple, and this is why I got it. (Shop and cost below are for the installation of my gears using this Royal Purple.)Helpful (3)
June 03, 2019
It was time to change the fluid in my differential and decided to try this product since I have heard great things about it. Well, I am a believer! Really reduced the noise.Helpful (6)
May 29, 2019
Royal Purple 75w140
Excellent product! Royal purple is the brand to use.Helpful (5)
May 01, 2019
Works will helps to add extra friction modifier. Eliminated the chattering from differential.Helpful (7)
April 22, 2019
for peace of mind I used this along with friction modifier. rear end is much quieter nowHelpful (5)
April 21, 2019
I run my car hard on the track and this oil never fails me. I see diff temps of 300 degrees, which is lower than what I used to get with other oils. No complaints!Helpful (5)
March 31, 2019
Keep it like new!
Love Royal Purple and wanted to make sure and protect my diff for years to come! It's great that the friction modifiers are already in the fluid!Helpful (5)
December 03, 2018
Love the friction characteristics of this oil!!!
If you have never used it or haven't done your research on this oil company, you are in for a treat! I've used pretty much all their products and have yet to be disappointed. Highly recommend!Helpful (6)
I am wondering ....why is it that it says I need 3 quarts of gear oil for my 8.8 rear end? But the Gear Kit only includes 2 quarts and friction modifier, which it also says comes in the Royal Purple Gear oil ? I just ordered 3 qts. and seems as I may end up with a spare!
As per the manual the 8.8 rear takes 4.25 pints so you will need the 3rd quart for that extra 4oz. Do not over fill or you will have fluid coming out of your axel seals sooner or later. Happy Motoring!
2003 Mach 1. One of your answers for a different year said friction modifier was needed with Royal Purple 75W-140. Royal Purple description says otherwise. What's the right answer?!!
The royal purple fluid does come with the friction modifier already included in the fluid so extra would not be needed on those vehicles, however, if doing a full fluid replacement and reseal or an overhaul (removing the cover) it is required to soak the clutches in the friction modifier fluid separately from the royal purple fluid to ensure a full seat with the clutches.
For a 2016 mustang gt performance package how many quarts do you need and do you need to add friction modifier
A 2015-2017 Mustang will require 2 quart bottles to fill, although not all of the gear oil will be used. You will also need 3-3.5oz of friction modifier.
I have a 2011 mustang V6 The owner manual says it only takes 1.5L which is less than 2 quarts. Should I still get 3 quarts or would 2 quarts be enough? I just don’t want to buy more than I would need. Thank you
I have a 2012 3.7 mustang with 3.31 gears, how much gear oil and friction modifier would I need for mine?
Three quarts of gear oil and one bottle of friction modifier are required for your use.
The 04 GT would take 2 quarts.
You will need 3 bottles of gear oil, though not all of the oil will be used.
A 75w90 will be thinner at higher oil temperatures than a 75w140. Both are the same thickness at lower oil temperatures. The 75w140 is said to have a wider viscosity range, when more accurately it would be a wider temperature range.
The 2014 mustang GT track packs came with a 75w-90 oil in the rear end from the factory but can be upgraded to the 140 if heavier track or drag racing will be occurring, also, 3-3.5OZ of friction modifier is needed.
Your 2016 Mustang GT would require (3) one quart bottles to fill the differential.
This gear oil would be perfect for your application.
Three (3) quarts of gear oil are required to fill a 8.8" Ford rear end.
Thank you for your question about the Royal Purple Max Gear 75w140 Gear Oil. Three (3) quarts of gear oil are required to fill a 8.8" Ford rear end.
Hello! An 07 GT takes 2 quarts of Gear Oil, and 4 oz of Friction Modifier.
A 2016 Mustang will require 2 Quarts of Gear oil with no rear cooler option, with the rear cooler, 3 quarts will be required. both will also require friction modifier. OEM the axles come with Motorcraft® SAE 75W-85 Premium Synthetic Hypoid Gear Lubricant.