PS Magazine - TB 43-PS-710

PS, The Preventative Maintenance Monthly

ISSUE 710

JANUARY 2012
PS Magazine - TB 43-PS-710 - Page 7 of 33
11
PS 710
JAN 12
T
he truck headshed tells us that there have been a lot of questions from the Feld
about the 4L80E HMMWV transmission and transmission control module (TCM)
E-PROM (or erasable programmable read-only memory). Maybe that’s because the
HMMWV once had 13 different transmissions with 13 different TCM E-PROMs for
each one. Thankfully, things have changed! Now there are only two transmissions
and two TCM E-PROMs.
The HMMWV parts manuals
will be updated with this info.
Here’s what you need to know
in the meantime:
All legacy A2/R1
“heavy variant” HMMWV
transmissions are being
replaced through attrition. So
when it’s time for a new one,
you’ll get a transmission, NSN
(containing the single-unit
E-PROM), NSN 2520-01-579-
1379.
All up-armored HMMWV
transmissions will also be
replaced by attrition. So you
will receive a transmission,
TCM (containing the single-
unit E-PROM), NSN 2520-01-
579-2302.
Note that the two TCMs are not interchangeable, so the legacy TCM will only
work with legacy transmissions. And the up-armored TCM will only work with
up-armored transmissions. Mixing the two will cause the transmission to go into a
“SA±E” mode and it won’t shift out of second gear.
±ED LOG shows that older two-piece E-PROMs (microcircuits) are still avail-
able until the supply runs out. They are only compatible with their respective
production year.
Year
Transmission
NSN 2520-01-
1995
1996
1997
1998
1999
2000
2001
399-4691
430-5291
439-6830
461-7072
461-7074
473-7410
489-0849
E-PROM
5962-01-
430-0182
430-0208
440-0368
470-4619
476-7772
480-5247
497-1611
Kit
N/A
57K3502
57K3523
57K3539
57K3549
57K3558
57K3569
Year
Transmission
NSN 2520-01-
1996
1997
1998
1999
2000
2001
430-2765
439-6831
459-8531
461-7077
475-1083
489-0850
E-PROM
5962-01-
431-5121
440-0369
470-4621
480-5246
480-5248
497-2519
Kit
57K3523
57K3522
57K3540
57K3548
57K3559
57K4408
HMMWV…
Replace
Old
Transmissions
by Attrition
This
table
lists
NSNs that
apply to
legacy
A2/R1
series
HMMWVs
with a
6.5L
naturally
aspirated
engine.
These NSNs are for up-
armored HMMWVs with 6.5
turbo-charged engines…
New TCM
with
single-unit
E-PROM…
…replaces
older
two-piece
E-PROM
will you
look at
this!?!
didn’t
you hear?
things are
different
now!
there are
only
two
choices!
there are
just too many
choices for
transmissions.
710 10-11.indd
1-2
12/6/11
1:58 PM
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