The turn signals stopped working in my truck today.

We check the brake light bulbs on both sides and they looked good, I
did have a missing back up light on the drivers side.  We tried the
emergency flashers and they didnt work either.  On this model the two
flasher relays are located in the fuse box, just inside the drivers
door on the side of the dash.
We switched the position of the two relays and the emergency flashers
worked, so we could feel the clicking in the top relay and called this
one the good one.  The other one we called the bad one.

These relays are both 552 can type relays, 12V - so I had my son call
two auto parts stores in town to get prices and see if they had any
diagnostic tests for these relays.  NAPA wanted $12 and AutoZone
wanted $9 and the AutoZone guy told him there are no tests, and there
is no way to test a relay to see if it is working.

I told my son to go get his DVM and I will show him how to test one.
We measured 54.6 ohms on the bad one, 53 ohms on the good one, and
52.5 ohms on the new one, and 14.43M ohms on a new long life
electyronic flasher.

We decided this wasnt much difference in resistance between good and
bad, so I cut the can off the bad one with a hack saw blade.  Then I
hooked up a power supply and set it to 12V and touched the contact to
the relay connectors and watched the metal band in the can flex over
and click with a current draw of about 130mA, but it was fast.  So I
told him there were two ways to test the relay and he accused me of
using expensive equipment, so we took it out and touched it to the
battery and make it click again (should have used a resistor in series
to limit the current but didnt think of that fast enough).

So off to the store we went and got the, about $6.99, Blazer FL552
Long life ele3ctronic flasher, variable load 11-15V 15A 2 pin
20-1035-4 Autozone, from Tiger Accessories Group, LLC liconshire, IL
60096 - this is a solid state relay with the 14.43M ohms.  We put this
in and it didnt work - not sure why?  I figured the system in 1995 was
not designed for this variable load relay, but it didnt work.

We returned this one and got the $3.99, 552 mechanical flasher in the
metal can and put this one in and it work - turn signals, emergency
flashers, back up lights, brake lights, etc.

So finally my question to the dodge truck/auto electric experts is if
this relay worked but had a slightly higher resistance would this keep
the turn signals from working and why?

Recall the bad relay had 54.6 ohms and over 12V, ohms law says it was
drawing 219mA; the good one had 53 ohms and this draws 226mA and the
new one was 52.5 ohms drawing 228mA.  Is this 7mA threshold
significant in this turn signal/flasher circuit or is there something
else I am missing?

Also if you can explain how these fascinating relays work, I would
like to know about that also.  I am sure they are some kind of thermal
relay.  What they look like is a blue metal shim in the center and
there is a small flat wire mayber 1.5mm wide and 15mm long and 0.5mm
thick that is connect across the corners of the blue metal shim, this
fmall flat wire is wound along its length with a copper looking small
diameter wire that is connected to the two connectors.  I assume the
current flowing through the wire heats up the flat wire and then we
have some bimetallic action between the flat wire and the blue shim,
and this make thes blue shim click back and forth as the wire heats up
and cools down?