Axle Winching (more uses
for your winch)

This is another idea that filtered down
from the rock crawling competitions to the recreational wheelers. The
basic theory involves attaching your front mounted winch to the front axle so
you can compress the front suspension when desired. I planned for this usage
when I built my buggy so my winch rope drops right down from the winch and I
hook the clevis on the end to a tab on the front axle. On a leaf sprung rig you
will need to route the winch rope to pull directly over the top of the axle
which may require a pulley or a cross member you can route the winch rope
around. (I suggest using winch rope since it can bend around tighter radii
than wire cable can)


Compressing the front suspension comes in
handy for steep climbs since it lowers your CG a bit, cuts down on axle hop and
can help provide more traction by shifting the weight of the rig around (imagine
the vehicle pivoting on the rear tires towards the rock face it is trying to
climb). One other benefit is it makes the obstacle feel less steep than it
really is since the front end is brought down and the front suspension is no
longer unloaded, this can provide a much needed boost of confidence to the
driver.

I have also found it useful to compress
the front suspension is some off camber situations. In the picture above I
compressed the front end to level the cab when my passenger side front tire
dropped into a hole. What I like about this is it allows me to run with
more up-travel on the suspension for smoother pre-running and allows for taller
belly clearance for crawling around in the rocks; when the time comes that I
need a lower cg or tighter suspension I can simply winch the front (and soon
rear) end down and reap the benefits of a lower and stiffer suspension.
As silly as it may sound I found the most
important detail when setting up the front winch was the placement of the
controller. The easier the controller is to reach the more likely your are
to use it. I tucked mine between the passenger seat and switch box so I
can comfortably reach the controller even when strapped in to the seat.
The next logical step is to have the
ability to compress the rear suspension, this should further aid stability in
some off camber situations and also help when driving down very steep inclines
by keeping the rear suspension from unloading. Unlike the front winch, the rear
mounted winch has a few additional challenges that must be overcome. First
you'll want a smaller winch out back to save weight and money. Most people
use a 1500-2500lb winch for the rear. These small winches are typically
light duty and should not be used as a limit strap so you will need to route the
cable around your limit strap and have a way allow for slack in the winch line
to keep the rope from unwinding on the drum. More on this in a moment.

I did some searching and found a fairly
inexpensive 2000lb ATV winch on E-bay that looked like it would work. The
specs on this winch are posted in the picture above, the most important feature
was a load holding brake. Many of the small winches do not have a brake so
look carefully at the specs. I also liked how the internal gears were
metal (some are made with plastic gears). The whole package included
wiring, an easy to mount switch to control the winch, a small mounting plate and
even a roller fairlead. After bidding I ended up paying $60+ shipping for
the winch.

I mounted the rear winch under the
passenger seat by installing a new cross member so the supplied mounting plate
could be welded between the existing and new cross member. I also eliminated the
fairlead mount from the mounting plate. I initially centered the winch on the
frame and then realized the motor stuck out far enough that it would
interfere with the upper link so keep in mind it will have to be offset slightly
to compensate for the motor. The winch original came with 50' of 5/32 wire rope.
I replaced this with 15' of 5/16 fiber winch rope I picked up from
www.mcmastercarr.com. The part
number is #2302T11 and includes a hook for $13.21. The line is rated for
1700lbs. McMaster-Carr also offers a 1/2" winch rope assembly for $17
which is rated for 3700lbs (#2302T12).

I routed the winch line over the rear
cross member by making a small roller using a pair of tabs and one of the
rollers from the supplied roller fairlead. I made the tabs high enough to
keep the rope captured and smoothed out their edges really well on a buffing
wheel.


Once the winch rope clears the roller it
attaches to the axle. If I need to I can go back and add a snatch block to
the axle, then route the winch rope back up to the chassis which would half the
load the winch line is seeing. To keep the winch rope taught but still allow
some play so the winch line does not act as a limit strap I attached a pair of
small bungee cords to the rear of the chassis and then looped them around the
winch line (seen in the second picture above). The only thing left to do is test
it.

Update 10-24-05 - I have been able to use the rear winch a few times, this
picture is from Collateral Damage, driving down the biggest ledge. Sucking
down the back end definitely helped, I think I would have gone over forward
without it because the rains had washed out a 3 foot deep hole at the bottom of
the ledge that I wasn't expecting. I do need to install some sort of
pulley to the rear axle to half the load on the winch rope, after the obstacle
above I noticed the winch rope was breaking.