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5/22/2019 11:03 AM  #1


What gear oil for 8" rear end in 65 mustang

Changing out the third member on my 65 from 2.79 to 3.55.. what gear oil to use? ( open diff)


If it aint broke, I have'nt tried to "Fix" it yet!
 

5/22/2019 11:42 AM  #2


Re: What gear oil for 8" rear end in 65 mustang

90wt gear oil


Cut to fit, Pound to shape, Paint to match
 

5/22/2019 12:49 PM  #3


Re: What gear oil for 8" rear end in 65 mustang

how much one bottle or two ?


If it aint broke, I have'nt tried to "Fix" it yet!
     Thread Starter
 

5/22/2019 1:19 PM  #4


Re: What gear oil for 8" rear end in 65 mustang

Buy 2 bottles and fill it up until if comes out the fill hole!!


John  -- 67 Mustang Coupe 390 5 speed
 

5/22/2019 3:52 PM  #5


Re: What gear oil for 8" rear end in 65 mustang

Wear latex gloves when you add that gear oil. Most nasty, stinky stuff ever.

 

5/22/2019 4:32 PM  #6


Re: What gear oil for 8" rear end in 65 mustang

josh-kebob wrote:

Wear latex gloves when you add that gear oil. Most nasty, stinky stuff ever.

Actually...while 90 wt is very bad, that friction modifier for a limited slip is about twiced as worser.

BB


"you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
 

5/22/2019 8:52 PM  #7


Re: What gear oil for 8" rear end in 65 mustang

Agree with bolted to the floor. No friction modier needed with am open diff.

 

5/23/2019 5:45 AM  #8


Re: What gear oil for 8" rear end in 65 mustang

It is the friction modifier that stinks.  The oil smells a bit, but the friction modifier is basically a revenge weapon.

 

5/23/2019 7:42 AM  #9


Re: What gear oil for 8" rear end in 65 mustang

 

5/23/2019 7:56 AM  #10


Re: What gear oil for 8" rear end in 65 mustang

 

5/23/2019 8:09 AM  #11


Re: What gear oil for 8" rear end in 65 mustang

for the last 10 years I have had  a wholesale card.  For individual  orders $100 plus it is delivered to your door.  I sell at cost for friends and am NOT a salesman.  ie  that $18 qt is $14

 

5/25/2019 8:36 PM  #12


Re: What gear oil for 8" rear end in 65 mustang

3.50:1, not 3.55:1


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

6/02/2019 4:24 PM  #13


Re: What gear oil for 8" rear end in 65 mustang

Not to sound like Don, but... Is it in yet?


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

6/02/2019 7:59 PM  #14


Re: What gear oil for 8" rear end in 65 mustang

MS wrote:

Not to sound like Don, but... Is it in yet?

??
Steve   I think it's TIME.  


 

 

6/04/2019 9:35 AM  #15


Re: What gear oil for 8" rear end in 65 mustang

Nope.. It was a fight to find the right axle seals.. The National brand ones were too small ( by 0.030").. now those are in..

the old gear is out.. all surfaces cleaned up.. now gonna do E brake cable change.. and then put the new 3.25's in :D


If it aint broke, I have'nt tried to "Fix" it yet!
     Thread Starter
 

6/05/2019 6:24 PM  #16


Re: What gear oil for 8" rear end in 65 mustang

The original gear oil was 90 wt mineral oil.  It only held up without issue for more years and miles than your new gear set will ever see. Undoubtedly, there are numerous oils now on the market that are viewed as superior.  For a new gear set, best to avoid the synthetics, as it does  not allow the gears to properly introduce themselves to each other.  Otherwise, you really cannot miss with whatever oil you use.  Just depends on how much you want to spend to be comfortable.  Without limited slip, any oils with friction modifier in their blend will give you no advantage but are otherwise useable.
Best
Al


Classic cars are full of surprises and almost none of them are good ones!
 

Board footera


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