68 Jp jpmagazine.com NOVEMBER 2019
YOUR JEEP
radiator shop c an even repair one or two
leaks in the core itself. Good radiator shops
will tell you if they can repair what you
have and for how much up front, so you
can weigh their prices against buying a
new one. But if you plan on keeping your
Jeep for a long time, we would recom-
mend investing in a quality all-aluminum
replacement. Fortunately for you, there are
several direct bolt-in radiator options for
your YJ from companies like Flex-A-Lite
(flex-a-lite.com) and Quadratec (quadratec.
com). Though more expensive, you will
upgrade the cooling capacity of your
Jeep significantly and should get years of
trouble-free use. Make sure you use good-
quality coolant to avoid any issues with
electrolysis, and remember to throw a new
thermostat in when you do the swap.
Caddy CJ-7
I’m seeking advice on CJ-7 leaf springs.
I believe I may need something a bit more
than a standard off-the-shelf lift kit. My
Jeep has a Cadillac 500, TH400 transmis-
sion, and Dana 300 transfer case. I’m in
the process of building Wagoneer Dana
44 axles. I run 33-inch tires and doubt I
would exceed 35-inch tires in the future. I
plan to retain the springs under axles for
simplicity. I’m looking for 2.5-inch-wide
front springs that move the axle forward
slightly and can handle the additional
engine weight.
John M.
Via email
That’s a lot of engine for a CJ-7, but it
sounds like a cool build. For starters, you
may not have as big of a weight problem
as you think. The weight of a Cadillac 500
varies a little depending on the sources we
found, but it’s safe to say that the engine
weighs 625-650 pounds fully dressed with
iron heads and intake. A fully dressed AMC
V-8 weighs about 550 pounds, while a
258ci I-6 weighs around 575 pounds. As a
result, you’re really only talking about a 50-
to 100-pound difference. Lift kit manufac-
turers design their springs around the
weight of the engine, but they often build
a little bit of extra rate into the springs with
the assumption that the end user will add
heavy accessories like a winch or a heavy-
duty bumper. As a result, you might be fine
with the Caddy engine, unless you’ve also
added some other heavy accessories to
the front end.
Unfortunately, because you’re doing
something outside the box, it’s going to be
difficult to find an off-the-shelf solution.
The stock front springs on your CJ-7 are
2 inches wide, and as you’ve probably
found, that is not a c ommon width. Other
than CJ lif t springs, your options are
limited. Going to a 2.5-inch-wide spring is
a good choice because it’s a much more
common width and opens up spring selec-
tion quite a bit, but it is going to take some
fabrication work since you’ll need wider
spring hangers to match the wider springs.
As we mentioned, off-the-shelf springs
might work just fine, especially if you go
with springs that are marketed as heavy
duty. If those prove to be not enough, we’d
experiment with rear YJ springs. Front
and rear YJ springs are dimensionally the
same, and we think rears would be a good
choice because they’re going to be the
right length to work well on your CJ while
also having some ex tra spring rate that was
originally done to keep axlewrap under
control. Running the spring backward will
also move the axle forward a little. You
could also experiment with FSJ springs,
but you may find their length and the
location of the centering pin problematic. If
we were in your shoe s, we’d build around
YJ springs, as there are lots of different YJ
lift springs on the market and you should
be able to find a combination that will work
well for your needs. Also keep in mind
that you can always add a leaf to the front
springs if you need a little extra support.Gas or Hydraulic?
I recently purchased new Wrangler
DuraTrac tires for my 2009 Wrangler. I also
bought the best set of Monroe gas-filled
shocks that my local chain store parts
re t ailer had. I am ver y happy with the
quality of both products. My question is
which is better, gas or hydraulic shocks?
Every auto parts store has given me a
different answer. This is my daily driver
and camping vehicle as well. It spendsmost of its time in the Great Lakes region. I
appreciate your time and enjoy the mag.
Ranger
Via emailFor an everyday driver and weekend
wheeler, either type of shoc k is just fine,
and you would probably notice little differ-
ence (if any) if good-quality, conventional
hydraulic shocks were installed on your
truck versus the gas-filled versions in
95 percent of the driving conditions you
will encounter. Explaining how a shock
absorber works would take up more space
than we have here, but there are some
excellent articles on the topic available
on our supersite, fourwheeler.com (such
as this one: fourwheeler.com/how-to/
suspension-brakes/129-1001-off-road-
shock-absorbers-101).
This is a bit of an oversimplification
because there are several nuances among
different shock manufacturers, but the
only real difference between hydraulic
shocks and gas shocks is that the latter has
a pressurized gas charge inside of it. Why?
Friction is created as a shock piston moves
through the hydraulic oil inside a shock
body, and this friction creates heat. As the
oil heats up, it has a tendency to aerate or
foam, which is a fancy way of saying that
air mixes with the oil. Air passes through
the valves in the shock piston much faster
than oil, which reduces the effective-
ness of the shock to control suspension
movement. This is referred to as shoc k
fade. Pressurizing the fluid in the shock
absorber reduces the tendency for the oil
to foam, so a gas shock will perform better
and longer in a really bumpy environment
where the suspension has to work hard,
such as when bombing down a fire road.
But during everyday driving situations like
taking the kids to school and going to the
grocery store, how the shock is valved has
more impac t on ride quality than whether
or not there’s a pressurized gas charge
present in the shock cylinder.
All that being said, there are some
other advantages to gas shocks. Since
they are more expensive to manufacture
and are usually sold as an upgrade over a
conventional hydraulic shock, most shock
manufacturers tend to spend more time
making sure the shock valving is right
for the application. They also often use
better-quality materials inside the shock
and exterior finishes that are more resis-
tant to the elements. It is more for these
reasons and the resistance to shock fade
that gas-charged shocks are often consid-
ered better than a hydraulic shock. But that
is not to say there aren’t some excellent
hydraulic shocks out there, including a few
that allow you to adjust the valving exter-
nally for the terrain you encounter. The
bottom line: If you spend a lot of time at
speed off the pavement, then gas-charged
shocks have an advantage. But for a rig
that spends most of its time on the street
and slow-speed off-road situations, a
quality set of hydraulics will work just as
well and often cost a little less.