[65fastback2+2]

my 65 is supposed to have a 3.00 locking differential per the vin info, etc. but only the back left wheel drives the car as far as i know, cause we took it to a place and they jacked the back left wheel up to test the tranny, the back right wheel stayed on the ground. am i thinking locking differential is something else?

[silo]

have you looked at the tag on the rear end? Or taken it apart to actually check? As far as I know all the factory rearends where limited slip.

[paustin]

What exactly does the limited slip mean?

[silo]

limmited slip basiclly means that which ever wheel will spin that is the one that drives the car. So if you get stuck in the snow or mud and only one tire spins, that is why.

[1998GT]

I though it was where if one starts losin traction, it gives power to the other wheel.. What was in that 67 Fastback in Bullit? Cuz like in that one part, he puts it in reverse and just smoked them goin back, only the left tire is smokin, then he puts it in drive and just smokes em only with the right tire though..

[mplumlee6]

from drivetrain.com

Ford cars and trucks from 1968 on have an axle code on the Certification Plate that can be used to determine if the vehicle is factory equipped with a limited slip differential. The Certification Plate can be located on the lock face of the left door edge. The plate layouts vary depending on the year, but in every case the axle code section is clearly marked as either "axle" or "ax". Ford axles codes contain one or two character. Any code beginning with a letter (an alpha code) indicates the vehicle is equipped with a limited slip differential EXCEPT as shown below. Some trucks with axle codes that are numbers only (numeric codes) are equipped with limited slip differentials. Please refer to the information below:
Differential cover/cover gasket shapes a common technique to determine ring gear diameter. Dana/Spicer Differential Parts bill of material number an excellant method to determine correct parts that are required.


Code
Positraction
Ratio

12 Conventional non-Positraction Differential 2.73

16 Conventional non-Positraction Differential 3.73

17 Conventional non-Positraction Differential 3.31

18 Conventional non-Positraction Differential 3.06

19 Conventional non-Positraction Differential 3.55

23 Conventional non-Positraction Differential 3.54

24 Conventional non-Positraction Differential 3.54

25 Conventional non-Positraction Differential 4.10

29 Conventional non-Positraction Differential 3.55

31 Conventional non-Positraction Differential 3.73

32 Conventional non-Positraction Differential 4.10

33 (1992-1998) Conventional non-Positraction Differential 3.54

33 (1999-2002) Conventional non-Positraction Differential 4.30

34 Conventional non-Positraction Differential 3.73

35 Conventional non-Positraction Differential 4.10

36 Conventional non-Positraction Differential 4.56

39 Conventional non-Positraction Differential 3.55

41 Conventional non-Positraction Differential 3.73

42 Conventional non-Positraction Differential 4.10

43 Conventional non-Positraction Differential 4.30

45 Conventional non-Positraction Differential 4.10

46 Conventional non-Positraction Differential 4.56

49 Conventional non-Positraction Differential 3.55

52 Conventional non-Positraction Differential 4.10

56 Conventional non-Positraction Differential 4.10

58 Conventional non-Positraction Differential 4.86

61 Conventional non-Positraction Differential 3.73

62 Conventional non-Positraction Differential 4.10

63 Conventional non-Positraction Differential 4.30

65 Conventional non-Positraction Differential 4.10

66 Conventional non-Positraction Differential 4.56

68 Conventional non-Positraction Differential 4.88

69 Conventional non-Positraction Differential 3.55

72 Conventional non-Positraction Differential 4.63

73 (1996-2000) Conventional non-Positraction Differential 5.13

73 (2002) Conventional non-Positraction Differential 4.30

75 (2002 Motor home - Dana 80) Conventional non-Positraction Differential Supply Bill of Material Number

75 Conventional non-Positraction Differential 5.38

78 Conventional non-Positraction Differential 4.88

81 Conventional non-Positraction Differential 3.73

82 Conventional non-Positraction Differential 4.10

83 Conventional non-Positraction Differential 4.30

86 Conventional non-Positraction Differential 4.56

88 Conventional non-Positraction Differential 4.88

95 (2002 Motor home - Dana 135) Conventional non-Positraction Differential Supply Bill of Material Number

95 Conventional non-Positraction Differential 5.38

98 Conventional non-Positraction Differential 4.88

B4 Limited Slip Differential 3.73

B5 Limited Slip Differential 4.10

B9 Limited Slip Differential 3.55

C1 Limited Slip Differential 3.73

C2 Limited Slip Differential 4.10

C3 (1992-1998) Limited Slip Differential 3.54

C3 (1999-2002) Limited Slip Differential 4.30

C4 Limited Slip Differential 3.73

C5 Limited Slip Differential 4.10

C6 Limited Slip Differential 4.56

C9 Limited Slip Differential 3.55

D1 Limited Slip Differential 3.73

D2 Limited Slip Differential 4.10

D3 Limited Slip Differential 4.30

D5 Limited Slip Differential 4.10

D6 Limited Slip Differential 4.56

E1 Limited Slip Differential 3.73

E2 Limited Slip Differential 4.10

E3 Limited Slip Differential 4.30

E6 (1992-1998) Limited Slip Differential 4.10

E6 (1999-2002) Limited Slip Differential 4.56

EW (1992-1999) Limited Slip Differential 4.10

EW (2000-2002) Limited Slip Differential 4.88

F1 Limited Slip Differential 3.73

F2 Limited Slip Differential 4.10

F3 Limited Slip Differential 4.30

F5 Limited Slip Differential 4.10

F6 Limited Slip Differential 4.56

F8 Limited Slip Differential 4.88

G3 Limited Slip Differential 4.30

G5 Limited Slip Differential 5.38

G8 Limited Slip Differential 4.88

GW Limited Slip Differential 4.10

H5 Limited Slip Differential 4.10

H7 Limited Slip Differential 3.31

H8 Limited Slip Differential 3.08

H9 Limited Slip Differential 3.55

K5 Limited Slip Differential 5.38

K8 Limited Slip Differential 4.88

KW Limited Slip Differential 4.10

W5 Limited Slip Differential 4.00



The following figure presents differential cover/cover gasket shapes. Counting cover bolts and cover shapes is a common method to determine which ring gear diameter differential you have in your rear wheel drive vehicles. See following paragraph for selection of correct Dana parts

.

When ordering Dana/Spicer Differential Parts provide bill of material number. This number is stamped on your right hand side axle tube. It's a number like 603XX-X, 604XX-X or 605XX-X. With this number you can tell exactly what components the factory used in the assembly of your differential. Plug the bill of material number in Dana's site, information is also provided should you want to change gear ratio.

[Jeff65]

Originally posted by silo
have you looked at the tag on the rear end? Or taken it apart to actually check? As far as I know all the factory rearends where limited slip.

AFAIK, this is not true. Most Mustang cars did not have traction-lok (limited slip) rear axles, most had open differential rear axles. Most common ratios were 2.79 and 3.00.

[Jeff65]

Originally posted by paustin
What exactly does the limited slip mean?

http://auto.howstuffworks.com/differential.htm

[65sohc]

As I recall, Ford called their limited slip differential "Equa-Lock" in those days. It was similar to GM's "Positraction" but didn't work as well. "Traction Lok" came along with the Fox bodies. The concept is that power is applied to the wheel with the most traction, so that if one tire slips power is transferred to the one that has more grip. One look at a pair of musclecars doing burnouts will make the distinction obvious. The one w/o limited slip spins the right rear tire only while the limited slip-equipped one leaves two nice black marks on the pavement. Obviously you'll jump off the line faster if both rear tires are contributing rather than just one. Very few early Mustangs had limited slip.