34 NOVEMBER 20194-WHEEL & OFF-ROAD 4WHEELOFFROAD.COM
ULTIMATE INTERNATIONAL
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The Cummins R2.8 crate engine comes with
just about ever y thing you need to make the
engine run, including the wiring harness, comput-
er, front accessories, belt, starter, Murphy gauge,
and a host of other bits. Add fuel and a battery
and you can start it right in the crate, and we did
just that w ith the DeRanged Rover’s R2 .8 l ast
year and the UACJ-6D’s R2.8 the year before that.3
The Tremec TR-4050 was set up by Silver
Sport Transmissions to have a fairly standard
six-bolt round bolt pattern common with Jeeps
and a matching 23-spline output. To mate the
transmission to the Cummins engine, we are
using a Quickdraw Brand bellhousing. This super-
beefy aluminum bellhousing mates the two
components perfectly and allows us to retain the
factory Cummins flywheel. It also includes a bul-
letproof clutch fork and throwout bearing that
works with standard Jeep TJ clutch hydraulics.4
The only modification we had to do to mate
the engine and transmission was havethe Cummins flywheel redrilled to accept a
standard GM pressure pl ate. Quickdraw of fer s
this service on an exchange basis, or you can
have the flywheel machined at any competent
local machine shop. We chose an 11-inch Cen-
ter force I I Dual Friction clutch because we’ ve
had excellent luck with them on several previ-
ous builds. The input shaft on the TR-4050 is
standard GM/Jeep 10-spline stuff, so an off-
the-shelf clutch kit worked just fine.5
Despite being brand-new products just
released on the market, everything
worked perfectly mating the Tremec TR-4050
to the back of the Cummins R2.8. The overall
length of the Tremec with the Quickdraw
bellhousing is 24^1 ⁄ 4 inches (the transmission
by it self is 19^1 ⁄ 4 inches). Unfor tunately, a
miscommunication between us and Offroad
Design resulted in our getting a Magnum
NP205 that wasn’t going to work, but we’ll
detail s w inging that combo on the back of the
Tremec in a future installment.6
In order to meet the emissions require-
ments on most newer vehicles, the R2.8
comes with a diesel particulate filter (DPF).
Though compact as DPFs go, it took up a lot
of real estate right where we needed it. Since
we’re working with an older vehicle that is not
subject to emissions laws in its home state,
we opted to replace the bulky DPF with a more
compact bolt-on exhaust flange from Axis
Industries. This allowed us the critical inches
we needed to make the engine fit in the com -
pact engine compartment and still clear the
front differential.7
You don’t want to hard-mount an engine
to the frame of anything but a racecar,
especially when the engine is a diesel. We
could have fabricated or own engine mounts,
but Axis Industries saved us a few valuable
hours with a set of engine side motor mounts.
These brackets bolt to the Cummins block and
include rubber isolators with simple two-bolt
attachments to your frame side mounts.2
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