Noise in Neutral
(a) Misalignment of transmission.
(b) Worn flywheel pilot bearing.
(c) Worn or scored countershaft bearings.
(d) Worn or rough reverse idler gear.
(e) Sprung or worn countershaft.
Excessive backlash in gears.
(g) Worn mainshaft pilot bearing.
(h) Scuffed gear tooth contact surface.
Use of incorrect grade of lubricant.
Noise in Gear
(a) Worn or rough mainshaft rear bearing.
(b) Rough, chipped, or tapered sliding gear teeth.
(c) Noisy speedometer gears.
(d) Excessive end play of countershaft gears.
(e) Refer to conditions listed under Noise in Neutral.
(a) Oil level too high.
(b) Wrong lubricant in unit.
(c) Non-shielded bearing used as front or rear bearing
cap where applicable.
(d) Seals defective, wrong type or omitted from bearing
(e) Transmission breather omitted or plugged internally.
Capscrews loose, omitted or missing from remote
control, shifter housing, bearing caps, PTO or
(g) Oil drain-back openings in bearing caps or case
plugged with varnish, dirt, or gasket material.
(h) Gaskets shifted or squeezed out of position, broken
gaskets with pieces still under bearing cap, clutch
housing, PTO and covers.
Cracks or holes in castings.
Loose drain plug.
(k) Oil leakage from engine.
Loose speedometer adaptor or connections.
Walking or Jumping Out of Gear
If the units are walking out of gear, it could be caused by:
opening, preventing full engagement, or
(b) An internal malfunction, such as worn clutching
teeth, allowing the transmission to shift out of
If a remote control is being used, make sure It is
functioning properly before the transmission is blamed
for the problem. Note whether the unit walks out of gear
under drive while pulling a load, or on a coast load. Also,
notice whether the gear hop occurs on smooth roads or
only on rough roads. Items that would prevent full
engagement of gears are:
(a) Improperly positioned forward remote control which
limits full travel forward and backward from the
remote neutral position.
(b) Improper length shift rods or linkage that limits travel
of forward remote from neutral position.
(c) Loose bell cranks, sloppy ball and socket joints.
(d) Shift rods, cables, etc. , too spongy or flexible, or not
secured properly at both ends.
(e) Worn or loose engine mounts If forward unit is
mounted to frame.
Forward remote mount too flimsy, or loose on the
(g) Set screws loose at remote control joints, on shift
forks inside remote or even inside transmission unit.
(h) Shift fork pad clips or groove in sliding gear or collar
Worn taper on gear clutch teeth.
Transmission and engine out of alignment either
vertically or horizontally.
A few items which could move the gear or shaft out of
proper position, particularly on rough roads are:
(a) Use of heavy shift lever extensions.
(b) Broken shift rod poppet springs.
(c) Worn shift rod poppet notches.
(d) Bent or sprung shift rods.
(e) Shift fork pad clips broken or missing.
Excessive end-play in drive gear, mainshaft or
countershaft, caused by worn bearings or retainers.
(g) Worn or missing thrust washers.