What is everyone running for rear diff fluid? I am installing a new diff cover this weekend and I already know the previous owner had 4:10s installed. Thanks In advance.
Rear diff fluid?
- Thread starter Cobertible01
- Start date
I'd go with Royal Purple.
Amsoil is Great BUT Jimmy is gonna suggest RP, haha!
I run royal purple as well. Expensive, but worth it in my eyes.
A synthetic 75W-140 GL-5 gear lube is required. You will need 1.5 quarts.
If you choose to use what I use that will be Royal Purple Max Gear 75W-140 (part #01301, quart bottle).
Friction modifier for the Traction Loc is included in the Max Gear formulation, so no additional will need to be purchased or addied.
American muscle claims 2.5 quarts to fill, I wonder why? I've noticed Uve said 1.5 before and never thought about it untill now, as I'm doing a gear swap this weekend.
Thanks Jimmy! What would you use for gasket maker for the diff cover?
The ultra grey RTV or the Ford Diesel grey RTV.
I've got the detroit truetrac...used valvoline for a few years..just changed it with advanced auto 80W90 gear oil....took almost exactly 2quarts.
The "old" Valvoline was clean as a whistle...but I am a mere DD.
Aside: I redid the PS and Trans fluid with valvoline maxlife ATF.
Maybe I'll wait a couple of summers and refill the diffy with some fancy stuff.
The "old" Valvoline was clean as a whistle...but I am a mere DD.
Aside: I redid the PS and Trans fluid with valvoline maxlife ATF.
Maybe I'll wait a couple of summers and refill the diffy with some fancy stuff.
That is for a solid rear where the oil travels down the axle tubes. IRS take 1.5 quarts max.
Ah great info! I have a solid axle now anyway and filled it with 3 so lucky me lol.
Gear oil for SVT cobra is 80w-90
according to the SVT supplement guide for the owners manual you are supposed to use a 80w-90 rear gear oil. The 75w-140 is for the regular GT with solid axel.
http://www.motorcraftservice.com/pubs/content/~WO1MUS/~MUS~LEN/43/01mussv1e.pdf
according to the SVT supplement guide for the owners manual you are supposed to use a 80w-90 rear gear oil. The 75w-140 is for the regular GT with solid axel.
http://www.motorcraftservice.com/pubs/content/~WO1MUS/~MUS~LEN/43/01mussv1e.pdf
FYI for the 2001 Cobra the SVT manual insert says to use 80w-90. The 75-140W is for the solid axle GT's.
Page 14
http://www.motorcraftservice.com/pubs/content/~WO1MUS/~MUS~LEN/43/01mussv1e.pdf
Yes I am bumping a year and a half old thread.
I acquired a used 99 stock IRS to replace the one currently in my car. I want to change the gear oil in it before I put it in my car.
I will be using 1.5q Valvoline 80w-90 oil, but I want to know what kind and how much friction modifier to use. Or should I just use RP and not worry about a friction modifier. Its just that RP is like 22 bucks a bottle and I have heard conflicting things on if it is even worth it.
Thanks for the help guys.
I acquired a used 99 stock IRS to replace the one currently in my car. I want to change the gear oil in it before I put it in my car.
I will be using 1.5q Valvoline 80w-90 oil, but I want to know what kind and how much friction modifier to use. Or should I just use RP and not worry about a friction modifier. Its just that RP is like 22 bucks a bottle and I have heard conflicting things on if it is even worth it.
Thanks for the help guys.
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Just saw this thread... would like to add this.....I run CenPeCo in all my cars....as synthetic is too slipper and WILL cause premature wear and slip. This is not my opinion this a tested in the field in various applications. PM me for any questions.
https://www.youtube.com/watch?v=pOdyRQU56Q0
https://www.youtube.com/watch?v=pOdyRQU56Q0
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