I have just changed the Serpentine belt on my 2006 Dodge Caravan 3.3L. I
have the two shop service manuals for the 2006 Caravan and the belt
tensioner, picture ( drawing )in the manual is not the same as on my
vehicle. The manual picture ( drawing ) indicates you use an open end
wrench on the back of the tensioner ( end opposite pulley, the spring end ).
It shows a tab you attach the open end wrench to. Well the tab on my
tensioner is about 1/64 inch and impossible to attach anything to.
What I did was use a 90 degree adjustable wrench, I have had for
decades. The jaws of the wrench is exactly parallel and you can be
accurate with the adjustment.
The wrench I have is NOT the 90 degree adjustable pipe wrench ( made by
Rigid and other companies )these do not have jaws that are exactly
parallel nor is the adjusting ring accurate, it is sloppy. However that
type of pipe wrench could possibly work, however it is not what I used.
What I used is basically a standard adjustable wrench a mechanic would
have in his tool box, except the jaws are at 90 degrees, it is 10 1/2
inches long.
I purchased a 3/4x17 inch piece of pipe from Home Depot, the type of
pipe you sometimes see them threading in the plumbing dept. I partly
flattened one end of the pipe and slid 4 inches of the adjustable wrench
handle into the pipe, to make the handle much longer ( 23 inches ), so
when you pull on it you can overcome the spring force of the belt
tensioner. The belt tensioner has a very strong spring and you cannot
use just the 10 1/2 inch wrench, I had to add the extra length of pipe.
I attached the adjustable wrench to the front of the tensioner ( where
the pulley is ) snugged the adjustment for the jaws, pulled the pipe
handle back. ( tensioner turns anti- clockwise with this pull ), slipped
a 3 inch long 2x4 piece of wood, between the lower control arm of the
wheel and the pipe handle. The tensioner relaxed about 3/4 inch. This
was enough to remove the belt and install a new one. ( actually nothing
was wrong with the old belt except it has 70,000km )

What surprised me was once you relax the tensioner, how easy it was to
remove the belt and how easy to install a new one. ( 2-3 minutes ).
Thread the belt last on the Crankshaft Pulley. Remove the 2x4 block of
wood. THAT'S IT. DONE.
P.S. It is only common sense that one will memorize or make a drawing of
how the belt is threaded on the different pulleys, BEFORE you remove it.

Denny B