I just switched to a SRA what do you guys suggest for the diff oil? I have the friction modifier but need the oil now...what do you guys run and how does it feel? :rockon:
Best Rear End Oil
- Thread starter Vnmous1_04
- Start date
I had the leaking diff... cover!!! went w/ford racing 4.10s = (street monster) Love Them!! i use redline oil for everthing!!!!!(motor, rearend,tranny,power steering and water wetter) car drives great:burnout::burnout::burnout:
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cobraracer46
Banned
Red Line synthetic oil company make the best rear end oil.
big fan of full synthetics - personally amsoil but for a street car i don't think you'll notice a difference between amsoil, royal purple, mobil 1, red line, etc. be careful, some differentials (auburn) require conventional oil, check with what your manufacturer recommends if you don't have the stock differential.
Still confused??? What gear oild can i use on the stock cobra diff? What weight are you guys using? I will be putting it back together on thursday so i need to know fast.
Thnks
Thnks
75-90w for stock, 85-140 for heavy duty use.....if u go synthetic, most contain friction modifier.....but as stated above be careful and read instructions if u are upgrading diff as well....I have an eaton posi in my fox and it is recommended to use conventional oil NOT synthetic......not sure how that differs from the stock cobra diff. Since they both have carbon fiber clutches....maybe some others will chime in....otherwise I like amsoil, royal purple then redline...in that order.
in my stock 03 GT rear end i used 75w140 royal purple. changed it about 30k miles ago, and i haven't had any problems yet. I was told to put it in the diff with nothing but its self, because it contains friction modifier (or it's own version)
You don't need vasoline if she's tight spit will do just right.
Oh that rear end.....
Oh that rear end.....
Ok this is the reason im confused i don't have a cobra but i purchased the diff from american muscle. Its the 8.8 31 spline that comes on the snakes and i'm going to install it on my 89 coupe. I talked to the guy that is going to do the gear swap and put everything back together and he told me to get "Lucas 85w-140". This guy has done two of my other cars in years back and i remember using a penzoil brand back in the day. In my area i cant get amsoil,redline without ordering it so im limited to royal purple and mobile 1 and these are synthetics. He recommends the lucas 85w-140 conventional oil.
thanks for the help.
The one thing I dont like about RP is its so dark to begin with its hard to tell how the fluid looks when you remove it from the diff. (had this problem with my g35) I like to use a honey colored gear oil that way you can at least have some point to judge how bad the fluid looks. Currently running Mobil1 in the Cobra 75W140 synthetic
Cool i went to advance auto and this is what they say an 03-04 cobra would take. I just cant figure out why this guy likes the 85w-140 conventional oil. I know there is other people out there that have used it and i just want to know why they when with it? I just dont want to cause any type of damage to the diff or will it make that much of a difference?
thanks again
Some rear ends only use conventional oil instead of using synthetic. That is the only reason I can come up with as for a weight difference. But you said you are using the same rear as the 03/04 cobra right? If so then 75W140 is correct and you can use synthetic.
Are the any brass parts in the tranny or diff on the 03-04's? If so gl-5's are a no go as most contain sulfur like RP which etches bass.
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