The Snowflake herald., 1921-11-18
NOISY GEARS
MEAN DANGER
Tell Story Owner Ought to Inter-
Dret in Terms of Dollars
and Cents.
LACK OF OIL CAUSES TROUBLE
Study of Rear Axle Construction and
OF Transmission Would Save Owner
Much Trouble and Some
Money.

It Is fact that a great number of
our cars are being driven over the
roads with noisy gears. This Is being
done either through ignorance or in
direct defiance Of that we'll established
rule 50 stitch I'm time, ETC." The noise
Of the gear besides being unpleasant,
tells story which the owner ought to
interpret in terms of dollars and cents.
without knowing anything at all about
q rear axle or transmission, the
average man should be able to know
the difference between rear axle that
is normal and one that is not. He may
not know the exact cause Of the
trouble or the manner in which 1t may
he reinedied. but he certainly ought to
he able to determine If it needs the
attention of a mechanic. The reason
for this immediate Interpretation is
TO save the owner money, for, like
case Of pneumonia developed from a
mere cold, If attention were given
early enough. the serious ailment would
not have developed. SO with gears.
Once their bearings begin to wear and
SO throw the gears out of their relative
running truth, the gears themselves
are affected so that IL the condition is
allowed to get worse, pretty soon the
gears cut and chip and then fail alto
gether
Two Out Of Five Noisy.
Observations were made at one spot
along frequented highway, where for
hours an average of 1000 cars per
hour passed. A fairly accurate check
was kept on gear noises on level
stretch and without exaggerating,
every two cars in five had noisy rear
axles. 1t Is doubtful If the owners of
the cars realize the meaning of such
noises, and If they know that In 80
per cent of the cases the condition
can be corrected for few dollars, per-
haps requiring only bearing adjust
meat. shifting of the different1al, a
quart or so of oil.
The. .srearsaxIe Is not the only offender.
The transmission gears need the
same protection. but usually they are
not at fault.
noisy gears come into being, one
should study the rear axle construc-
tiOn The driving piniOn at the end of
the propeller shaft is mounted usually
on two bearings. This piniOn meshes
with the large or ring gear of the diff
ferential unit. the unit itself being
mounted on two bearings which rest
in the. differential housing. In order
that the ring gear and the pinion do
their work without noise the teeth of
these gears must mesh properly. II
Che correctness of the mesh is de-
stroyed then noise results. Should the
piniOn shaft (hence the piniOn itself)
move relative to the ring gear the
tooth contact is at once changed and
you get noise. The noise is not nee
essarlly a steady one, but 1t may be
interrupted, due to the fact that the
new areas of contact of the teeth are
not all alike. There may be high
spot on one or two or more teeth and
when these high spots are struck the
noise changes.
Lack of fabrication.
The pinion bearings may be Of the
ball or roller type and there is, in
most cars. means of adjustment of
the bearings after they have been
worn slightly. The cause of the wear
may be natural. but in nine out of ter
cases 1t is due to lack of fabrication
The differential bearings are not IN
like the pinion bearings in the effect
they have no gear noises. These bear
Ings If worn even slightly will allow the
whole differential unit to shift side
ways and so disturb proper gear mesh
Once they start to wear and permit
this action, the wear is rapidly accel
Grated so that in a very short time
there Is no definite tooth contact.
The time to stop the gear noises is
Immediately they appear 1t is
cheaper for you and better for the car