Our group has been investigating whether or not engine oil coolers
were installed from the factory on 1971 429 SCJ Mustangs. We have yet to find
one that the owner believes was factory installed - if you believe you have one,
please contact the webmaster;
However, oil coolers were certainly installed by dealers and owners. And a
special kit with D1ZZ part numbers was released. It could be that the D1ZZ kit
was originally intended for the 71 Boss 302, which had been planned for
production in 1971 (but was dropped in favor of the Boss 351) as evidenced by
this scan from the 1971 Car Shop Manual Volume 2 - Engine, page 21-21-11 below
left and a Ford Engine Division internal document* at right;
* Courtesy of the
Boss 302 Registry
Below is an Oil Cooler Installation Diagram and component
parts list from Ford's "Muscle Parts Story on the 302 Boss, 351 C and 429 Wedge
- Supplement No. 2". This diagram shows the installation of an oil cooler on a
70 Torino. Since the Torino and 71 Mustang used the same Radiator Support sheet
metal, this diagram may be helpful to those wanting to install an Oil Cooler on
a 71 429 Mustang;
(Note: Click thumbnails to enlarge pictures)
Below are some of these special D1ZZ components that we have found.
(Note: Click thumbnails to enlarge pictures)
Here's Where We Believe Ford Intended
the Oil Cooler to Mount
The photos above show the oil cooler installed on a '71
Mustang in what we believe is the location Ford had intended. The
installation was done using
the correct* upper and lower brackets for the '71 Mustang and located the only way they will fit correctly
without cutting and/or hammering (which weren't the intended procedures on the
People who try to install a cooler on a 71 Mustang often do not know where to put it or what brackets
and hoses to use, so they try to
copy the 69-70 Mustang installation, which isn't correct for a 71 Mustang.
The never-produced 71 Boss 302 Mustang's cooler was intended to be
installed the same way as it was on a `70 Torino, which shares the same
radiator support as the 71 Mustang. The 71 Mustang intended to use the
Torino's lower rear facing D0OE-B bracket, and a modified top bracket, but
due to a difference in the width of the Torino and Mustang hood latch
bracket. (The top Torino D0OE-B rear facing cooler bracket didn't work on
the 71 Mustang) Ford had to come up with a new D1ZE `71 Mustang rear
facing top bracket to make it all work on the 71 Mustang. The new 71
Mustang only D1ZE cooler hoses were also necessary. The correct cooler
part numbers for the 71 Mustang installation are all listed in the 72 Ford
O.H.O Muscle Parts book shown at the bottom of this page.
* We say correct based on Ford's 71-72 O.H.O (Muscle Parts) parts book
which lists the Ford part numbers for the upper and lower brackets needed
for the oil cooler kit installation on the '71 429 SCJ Mustang.
These pictures shows the D1ZZ upper oil cooler bracket
(from just about every angle imaginable!).
The upper bracket part# is D1ZZ-6B633-A and the number stamped on it is
A Theory About the Notch on the side of the bracket...
See the cut away "notched" area by the bolt hole?
We see no
reason for this notch on a '71 Mustang application. However, we believe it
might have been required to clear the grill support on the
never produced '71 Cougar Eliminator with a Boss 302 engine. To support
this theory, the photo below shows the '71 Cougar Radiator support (common
part with '71 Mustang) with a red overlay of the top oil cooler bracket's
presumed design intent location. Note how the notch fits almost perfectly to
clear the grill support bracket on the '71 Cougar!
The lower oil cooler bracket
part number is D0OZ-6B634-B and the
number stamped on it is D0OE-6B634-B.
Below is the D0OE-6B634-A lower oil cooler bracket. Although similar in
appearance to D0OE-B, the fore/aft location of the two "U" shaped supports
Various Owner-installed oil coolers on '71 Mustangs
The three oil cooler installation photos in this row
are of owner installed coolers. We have yet to find one that was a factory
This picture shows an installed view of the oil
filter adaptor and cooler lines.
The oil cooler lines are visible in the lower portion
of the above photo.
This picture shows an NOS D1ZZ-6A715-A oil cooler line,
an NOS D1ZZ-6A715-B oil cooler line, an NOS D1ZZ-6881-A block adaptor and
a D1ZZ-6A636-A gasket.
This is a close up shot of the oil cooler heat
Oil Filter Adaptor
These are close ups of the D1ZE-6881-AA oil filter adaptor
(note the D1ZZ version is the service replacement). Note
that we believe the D1ZE Mustang hose ends were straight (note that some
examples shown here have the Torino style 45 and 90 degree ends).
Oil Filter Adaptor to Block gasket
This complete oil cooler kit was recently sold on Ebay.
|Oil Cooler Lines
The top D1ZZ hose was 39" long and the
lower hose was 32". Both hoses used the straight steel Aeroquip hose ends(size
as shown in the diagram above left.
Oil Cooler Component List
These are cooler part numbers for the 71 429 SCJ "Mustang" from
Fords 71-72 O.H.O (Muscle Parts) parts book:
C9OZ-6A642-A Oil Cooler Assembly
D1ZZ-6A715-A Hose Assembly- Inlet-71
D1ZZ-6A715-B Hose Assembly-Outlet-71
D1ZZ-6881-A Adapter-Oil Filter-71
BTW- The D1ZZ upper bracket became the service part for the original
Boss 302 upper bracket!
The article above is from "Ford Mustang - 1967 - 1973" (Brooklands
Books). It contains a period review of the 1971 429 SCJ Mustang and indicated
that the 71 429 SCJ Mustang did not require an oil cooler. This is the only
written period information found to-date referencing the factory status of an
engine oil cooler.
Fairchild's 429 CJ Mach 1