IN ORDER--

Ford 8+9 inch,
 Small Wheel Bearings-
most common car housing, but also found in some Bronco and others
(All will use 3/8 bolts- uses 9/16 wrench)
X= 3.375 Y=2.00 ** Wheel Bearing Dia= 2.835

Big Bearing Ford 9 inch(early style)-

"EARLY BIG BEARING"
from 1957 to mid 70's, usually only in heavy cars,
a few big engined vehicles and some trucks+vans
(MOST will use large 1/2 inch bolts-3/4 wrench, BUT a small few may use 3/8 bolts)
X= 3.50 Y= 2.375 *** Wheel Bearing Dia= 3.15

"Late" Big Bearing Ford 9 inch
sometimes called "Torino" even tho the main use was in pickups and vans
mid 70's to the last of the 9's in the early 80's
(ALL will use the 3/8 bolts and 9/16 wrench)
Easily confused with the Small Bearing- measure "X" carefully
X=3.562 Y= 2.00 *** Wheel Bearing Dia= 3.15

80's and 90's Ranger Mustang Bronco etc
8.8 and 7.5 FORD (c-clip rear very similar to GM)
Started appearing in cars around 1980??, the 8.8 later replaced
the 9 inch entirely in the mid 80's even in vans and pickups.
Bearing rollers ride directly on the axle surface. Inspect the axles.
X= 3.410 Y= 2.00 Z= 3.375

GM CHEVY 10 Bolt + 12 Bolt

Small Pattern
The most common older pattern.
Mid-size, and most Chevy cars 60's, 70's and
possibly some early 80's.. (used on c-clip rears ONLY)
the 3-1/8 BY 2-7/16 BY 2-5/8 pattern which is- 3-1/8
(bolt-center to bolt-center) between the top two housing-end bolts
holding on the backing plates, by 2-7/16 between the top bolt and bottom
bolt (center-to-center), and 2-5/8 between the centers of the two bottom
bolts.

10 BOLT CHEVY

  SMALL pattern with c-clips
(1965 to late 70's early 80's??)

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Large Pattern (C-clip and non C-clip)(Mid 50's to around 1980?)
(B) the less used, but still common mid 50's Chevy, BIG car
Mid-50's, Some but not all, 1960's cars, and most pickups thru the 70's.
3-3/8 BY 2-11/32 (or 2-5/8) pattern. This pattern sometimes uses the
3-3/8 measurement between the top two bolts or sometimes turns the
"3-3/8 by 2-5/8" pattern 90 degrees so the 3-3/8 may be the
top-to-bottom measurement.

10 BOLT CHEVY
 12 BOLT CHEVY
Large Pattern
3-3/8 BY 2-11/32 (or 2-5/8)

With or without c-clips
(1965 to late 70's early 80's??
pickups, big Impala, etc.)
AND- 1955-1964 NON-C-Clip
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