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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Changing diff fluid in an 8"

  • Thread starter Thread starter peterchase
  • Start date Start date May 27, 2004
P

peterchase

New Member
Aug 22, 2001
5
0
0
Athens, GA
May 27, 2004
#1
  • May 27, 2004
  • #1
What's the easiest way to change the diff fluid out of an 8" rear end? I was hoping to be able to pump out the fluid from the filler hole and then just pour the new fluid in. Is this possible or do I have to take out the driveshaft and unbolt the 3rd member?
Thanks,
Pete
 

taylor4g63

Founding Member
May 6, 2002
921
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0
Asheboro, NC
May 27, 2004
#2
  • May 27, 2004
  • #2
Pretty sure your gonna have to unbolt the 3rd member and let it all out that way. Thats the only way i can think to do it...
 

Great68

Founding Member
May 16, 2002
691
0
16
Victoria BC
May 27, 2004
#3
  • May 27, 2004
  • #3
Trying to pump it out of the filler hole will not get all the old fluid out.
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
May 27, 2004
#4
  • May 27, 2004
  • #4
look at the bright side, it beats changing ATF.
 
P

peterchase

New Member
Aug 22, 2001
5
0
0
Athens, GA
May 27, 2004
#5
  • May 27, 2004
  • #5
It seems to me that taking off the transmission pan is easier that pulling apart a whole rear end.....
 

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
May 27, 2004
#6
  • May 27, 2004
  • #6
Yeah, and once you take off the tranny pan, you can install a new one iwth a damn drain plug.
 
M

Mosse

Founding Member
Oct 22, 2002
229
0
0
Finland, Tampere
May 27, 2004
#7
  • May 27, 2004
  • #7
Just lift put your car on jack stands, and unscrew those u-bolts, and u-bolts holding driveshaft. Then flip the whole rear 90 degrees. This is the way to get all the debris out, and to be sure everything is ok.

Personally I don´t have to do this, cause my pinion gear came to see me...
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
May 27, 2004
#8
  • May 27, 2004
  • #8
peterchase said:
It seems to me that taking off the transmission pan is easier that pulling apart a whole rear end.....
Click to expand...
Messier too!!
 

6Stang7

New Member
Jun 1, 2003
1,470
0
0
Livermore, CA
May 28, 2004
#9
  • May 28, 2004
  • #9
Are you doing this for regual service, or after the 500 mile break in that comes with new gears. If it is for 500 mile break in, then you need to take the 3rd member out, so you can clean out all that metal debri out in the bottom of the housing. Otherwise, just get a pump like people have suggested and do it that way. Just drive your car around for awhile before you suck the oil out to get it nice and hot. 80W90 isn't the easiest to suck out when it's cold.
 
R

Ronstang

New Member
Apr 4, 2004
1,294
0
0
Houston Texas
May 28, 2004
#10
  • May 28, 2004
  • #10
Since you basically have to take the whole rearend apart to do this job correcty I suggest you order a largemouth drain from Currie or Moser and take the rearend housing out and take it to a welder and have them install it for you.....oil changes will then take about 10 minutes. If you have a welder or access to one you can accomplish this in the car if you are talented.
 

Gummi Bear

New Member
Sep 29, 2003
86
0
0
Arlington, Texas
May 28, 2004
#11
  • May 28, 2004
  • #11
Since I change the fluid in my diffs pretty often, I put a drain plug in the bottom of the housing. Drill, tap, use a recess Hex bolt with plenty of loctite, and voila! Quick and simple drain. I used a 1/4" plug, and it works pretty well. I can change my oil in about the length of time it takes me to suck down a beer.
 

taylor4g63

Founding Member
May 6, 2002
921
0
0
Asheboro, NC
May 29, 2004
#12
  • May 29, 2004
  • #12
6Stang7 said:
Are you doing this for regual service, or after the 500 mile break in that comes with new gears. If it is for 500 mile break in, then you need to take the 3rd member out, so you can clean out all that metal debri out in the bottom of the housing. Otherwise, just get a pump like people have suggested and do it that way. Just drive your car around for awhile before you suck the oil out to get it nice and hot. 80W90 isn't the easiest to suck out when it's cold.
Click to expand...


never heard you need to change the oil after the 500 miles. Guess i need to do that sometime soon then.
 

blue66tang

Founding Member
Jan 20, 2001
1,092
0
0
Medford, OR
May 29, 2004
#13
  • May 29, 2004
  • #13
taylor4g63 said:
never heard you need to change the oil after the 500 miles. Guess i need to do that sometime soon then.
Click to expand...

Me either, i put my richmond gears in not to long ago either, and the instructions didnt say anyting
 
T

toyshop

New Member
Feb 29, 2004
28
0
0
May 29, 2004
#14
  • May 29, 2004
  • #14
Bore a hole in the crazy thing, clean it out, weld in a fitting you can plug up, and there you have it- fluid changed without removing the 3rd member.
 

MustangPaul

Founding Member
Jun 20, 2002
514
0
0
South East Louisiana
May 29, 2004
#15
  • May 29, 2004
  • #15
Gummi Bear said:
I can change my oil in about the length of time it takes me to suck down a beer.
Click to expand...

Gummi--Better have another one to make SURE that all of the oil has dripped out. . . .
 
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