gear oil weight and how much?
12-20-2009, 09:39 PM
#21
4th Gear Member
Join Date: Nov 2007
Location: NJ / MA
Posts: 1,337
Looks like an MGW... cant wait for mine...
im runnin 75w90 royal purple, thats what it came with(well, not the royal purple part), and what it had on the tag. might consider swapping, but im not sure if it makes too much of a difference???
im runnin 75w90 royal purple, thats what it came with(well, not the royal purple part), and what it had on the tag. might consider swapping, but im not sure if it makes too much of a difference???
12-21-2009, 02:56 AM
#22
TECH SAVANT
Join Date: Dec 2006
Location: Saint Augustine, FL
Posts: 10,938
It is an MGW, here's a link to my write-up about same.
As to the gear oil, if I had 75W90, 80W90, or whatever hypoid rated gear oil in the rear-end, and did not race or pound on the car a lot, I'd not bother to change it out--maybe, read more below.
You will get slightly better fuel economy with the thinner oil--this of course is at the expense of accelerated wear of the gears, however with light to moderate duty we're talking about 200,000 miles vs. 250,000 miles...
--------------------------------------------------------------
In further researching the axle tag issue I found this TSB (04-24-20) which states in part:
and;
The TSB doesn't say so, however apparently there were some vehicles that were incorrectly filled with and tagged for 75W90 gear oil, which causes premature wear of the LSD clutch packs.
The fact that it's a TSB and not a recall indicates that some vehicles may never experience the problem (until after they are off warranty); this makes the real question "Do you feel lucky today?".
As to the gear oil, if I had 75W90, 80W90, or whatever hypoid rated gear oil in the rear-end, and did not race or pound on the car a lot, I'd not bother to change it out--maybe, read more below.
You will get slightly better fuel economy with the thinner oil--this of course is at the expense of accelerated wear of the gears, however with light to moderate duty we're talking about 200,000 miles vs. 250,000 miles...
--------------------------------------------------------------
In further researching the axle tag issue I found this TSB (04-24-20) which states in part:
Refill axles with 4 oz. Friction Modifier (XL-3) and the necessary amount of Rear Axle Lubricant XY-75W140-QL, regardless of the axle lubricant originally used in the axle. Fill to capacity recommended in the Workshop Manual.
AXLE FLUID REQUIREMENTS HAVE BEEN CHANGED. ALL VEHICLES BEING REPAIRED BY THIS TSB MUST HAVE REAR AXLE LUBE XY-75W140-QL INSTALLED, IN PLACE OF XY-75W90-QFEHP. AS PART OF THIS REPAIR, CHECK AND REPLACE IF NECESSARY THE CURRENT XY-75W90-Q“FEHP” METAL TAG, WITH A NEW 75W140 TAG (F3TZ-4121-AA).
ADDITIONALLY, REMOVE THE MULTI-COLORED LABEL WHICH IS LOCATED ON THE RIGHT SIDE AXLE TUBE, OR BLOCK OUT ANY/ALL “FEHP” OR “75W90” REFERENCES ON THE LABEL.
ADDITIONALLY, REMOVE THE MULTI-COLORED LABEL WHICH IS LOCATED ON THE RIGHT SIDE AXLE TUBE, OR BLOCK OUT ANY/ALL “FEHP” OR “75W90” REFERENCES ON THE LABEL.
The fact that it's a TSB and not a recall indicates that some vehicles may never experience the problem (until after they are off warranty); this makes the real question "Do you feel lucky today?".
12-21-2009, 12:19 PM
#23
4th Gear Member
Join Date: Nov 2007
Location: NJ / MA
Posts: 1,337
awesome. thanks for the info. will change it after the holidays. figures that the shop that also did my 3.73's didnt read or know about TSB's, and also filled my rear with 75w90 (in 2007). i havent pounded on it too hard, so i dont spose theres too much damage if any.
12-02-2010, 02:42 AM
#26
2nd Gear Member
Join Date: Jul 2010
Location: Adams,MA
Posts: 454
I change my differential fluid every two years or 20K miles whatever comes first
and everytime I change it the differential fluid is dirty.The rear end tag on my
1996 Ford Mustang GT says 75W90.I always use two quarts of 75W90 Mobil 1 synthetic
gear oil and one 4 oz. bottle of Ford Motorcraft friction modifier and I never have had
a problem.One of my friends has a 2001 Ford Mustang GT and the tag on his rear end
says 75W140 so,Cliffy is correct you should use a 75W140 gear oil.Although I belive
you should only use two quarts of gear oil and one 4 oz. bottle of friction modifier.
I know Mobil 1 Synthetic gear oil doesn't have the friction modifier additive in it and
you should add it if you use this brand gear oil.Also the Royal Purple gear oil does have the
friction modifier additive already in it and if you get this brand gear oil make sure you
get three quarts.Flushing and refilling your differential fluid is one of the most neglected
maintenance services and you should always change your differential fluid on time every
time.Also I recommend using a synthetic gear oil in the rear end of your Ford Mustang.
and everytime I change it the differential fluid is dirty.The rear end tag on my
1996 Ford Mustang GT says 75W90.I always use two quarts of 75W90 Mobil 1 synthetic
gear oil and one 4 oz. bottle of Ford Motorcraft friction modifier and I never have had
a problem.One of my friends has a 2001 Ford Mustang GT and the tag on his rear end
says 75W140 so,Cliffy is correct you should use a 75W140 gear oil.Although I belive
you should only use two quarts of gear oil and one 4 oz. bottle of friction modifier.
I know Mobil 1 Synthetic gear oil doesn't have the friction modifier additive in it and
you should add it if you use this brand gear oil.Also the Royal Purple gear oil does have the
friction modifier additive already in it and if you get this brand gear oil make sure you
get three quarts.Flushing and refilling your differential fluid is one of the most neglected
maintenance services and you should always change your differential fluid on time every
time.Also I recommend using a synthetic gear oil in the rear end of your Ford Mustang.
12-02-2010, 05:49 AM
#27
I change my differential fluid every two years or 20K miles whatever comes first
and everytime I change it the differential fluid is dirty.The rear end tag on my
1996 Ford Mustang GT says 75W90.I always use two quarts of 75W90 Mobil 1 synthetic
gear oil and one 4 oz. bottle of Ford Motorcraft friction modifier and I never have had
a problem.One of my friends has a 2001 Ford Mustang GT and the tag on his rear end
says 75W140 so,Cliffy is correct you should use a 75W140 gear oil.Although I belive
you should only use two quarts of gear oil and one 4 oz. bottle of friction modifier.
I know Mobil 1 Synthetic gear oil doesn't have the friction modifier additive in it and
you should add it if you use this brand gear oil.Also the Royal Purple gear oil does have the
friction modifier additive already in it and if you get this brand gear oil make sure you
get three quarts.Flushing and refilling your differential fluid is one of the most neglected
maintenance services and you should always change your differential fluid on time every
time.Also I recommend using a synthetic gear oil in the rear end of your Ford Mustang.
and everytime I change it the differential fluid is dirty.The rear end tag on my
1996 Ford Mustang GT says 75W90.I always use two quarts of 75W90 Mobil 1 synthetic
gear oil and one 4 oz. bottle of Ford Motorcraft friction modifier and I never have had
a problem.One of my friends has a 2001 Ford Mustang GT and the tag on his rear end
says 75W140 so,Cliffy is correct you should use a 75W140 gear oil.Although I belive
you should only use two quarts of gear oil and one 4 oz. bottle of friction modifier.
I know Mobil 1 Synthetic gear oil doesn't have the friction modifier additive in it and
you should add it if you use this brand gear oil.Also the Royal Purple gear oil does have the
friction modifier additive already in it and if you get this brand gear oil make sure you
get three quarts.Flushing and refilling your differential fluid is one of the most neglected
maintenance services and you should always change your differential fluid on time every
time.Also I recommend using a synthetic gear oil in the rear end of your Ford Mustang.
Quote: Bladerunner
Good job nice write up!
Flushing and refilling your differential fluid is one of the most neglected maintenance
services.Definitley make sure your differential fluid is changed on time or you are
putting your whole rear end in jeopardy.I change my differential fluid every two years
or 20K miles whatever comes first and everytime I change it the fluid is dirty.
I recommend always using a synthetic differential fluid when you change your differential
fluid. I like to use Mobil 1 75W90 Gear Oil everytime I change mine and don't forget the
friction modifier!
Good job nice write up!
Flushing and refilling your differential fluid is one of the most neglected maintenance
services.Definitley make sure your differential fluid is changed on time or you are
putting your whole rear end in jeopardy.I change my differential fluid every two years
or 20K miles whatever comes first and everytime I change it the fluid is dirty.
I recommend always using a synthetic differential fluid when you change your differential
fluid. I like to use Mobil 1 75W90 Gear Oil everytime I change mine and don't forget the
friction modifier!
Last edited by uberstang1; 12-02-2010 at 06:21 AM.
12-02-2010, 06:11 AM
#28
It is an MGW, here's a link to my write-up about same.
-
In further researching the axle tag issue I found this TSB (04-24-20) which states in part:
and;
The TSB doesn't say so, however apparently there were some vehicles that were incorrectly filled with and tagged for 75W90 gear oil, which causes premature wear of the LSD clutch packs.
The fact that it's a TSB and not a recall indicates that some vehicles may never experience the problem (until after they are off warranty); this makes the real question "Do you feel lucky today?".
-
In further researching the axle tag issue I found this TSB (04-24-20) which states in part:
and;
The TSB doesn't say so, however apparently there were some vehicles that were incorrectly filled with and tagged for 75W90 gear oil, which causes premature wear of the LSD clutch packs.
The fact that it's a TSB and not a recall indicates that some vehicles may never experience the problem (until after they are off warranty); this makes the real question "Do you feel lucky today?".
Last edited by uberstang1; 12-02-2010 at 06:20 AM.
