The “No Dirt” Jeep
WORDS Jim Sherman
Hey off road Jeep people stop reading. Since
the dawn of time Jeeps have been legends off
road. The Jeep Grand Cherokee SRT is not going to join the ranks of the awesome off-roaders.
This Jeep is a pavement-only SUV. Don’t get me
wrong I’m not in anyway bashing this Jeep, it is
awesome, powerful, fun and a great look.
When I first moved into this Jeep I was immediately impressed. Chiseled lines and an aggressive look makes this thing look mean. Slide into
the seat and it is just inspiring. The materials used
and the overall design is definitely high quality.
The seats are supportive and the major driver
controls are in the right places. Uconnect, Chrysler’s universal driver interface, is just so easy to use.
Bright clear screen and logical menu system. This
SRT has got all the goodies auto-climate control,
heated seats, heated steering wheel and a great
sound system. She’s a keeper.
Time for some tech talk and a reality check.
In 2015 the SRT gets the 6.4L Hemi. Jeep (Chrysler) claims 470 crank horsepower and 465 ft/lbs
of torque for this beast of an engine. That power
gets to the ground through an 8-speed transmission mated to an AWD system. A typical automatic transmission and AWD combination
will use 25% of the power resulting, in this case,
in a loss of 117hp. By calculation that means on
a wheel dyno we should see around 350whp
(wheel horsepower). Now I use the word typical because every transmission is different, for
example Porsche’s PDK automatic transmission
only uses 10% of the power similar to a true manual transmission. I took this SRT to my friends at
Auto Science in Carrollton, TX to see what it does
on an AWD dyno and in walks the reality check.
The SRT put down a disappointing 306whp or a
transmission/driveline loss of 35%. The massive
amount of fluid that has to be pumped through
that large of a transmission takes a lot of energy
plus a couple of differentials and a transfer case it
all makes sense.
40 CarGuyMagazine.com