i know this is pretty basic stuff for most people but i figured it would be good to have around incase someone forgets something or someone new has a question. i have a lot of info that im gonna put in here but give me some time because some of it is really long.
Manual transmission diagnosis
Transmission sticks or locks in gear
bearing noise
countershaft bearings
counter shaft bearings
gear noise
Transmission jumps out of direct drive only
Transmission jumps out of gear
Gear clash (grinding) during shifting
Differential
Gear noise
coming soon: brake diagnosis (its long so give me some time)
Manual transmission diagnosis
Transmission sticks or locks in gear
- clutch not releasing
- stick interlock or detent plugs
- shift linkage out of adjustment
- sliding gears tight on shift splines
- peened over teeth on synchro sleeves
- lack of lubrication
bearing noise
- in all gears except direct drive
countershaft bearings
- in all gears when moving
- with clutch engaged (in neutral)
counter shaft bearings
- with clutch fully disengaged
gear noise
- whine in one gear only
- clunk in one gear only
- clack in one gear only
- tranny noise in all gears
Transmission jumps out of direct drive only
- excessive end play of input shaft
- high gear synchronizers worn or broken
- worn front case bearing
- shift linkage not fully engaging
- worn shift forks
Transmission jumps out of gear
- shift linkage worn or misadjusted
- insufficient spring tension of detent springs
- misalignment or loose transmission or bellhousing
- pilot bearing badly worn
- shift fork, lever, or shaft is bent or worm
- badly worn transmission bearings
- worn synchronizer hub or broken keys
- excessive play in output shaft
- bad mounts
- clutch free travel excessive
- clutch does not fully release
- sliding gears or synchro rings binding
- sliding gear teeth damaged
- synchronizer worn or damaged
- shift mechanism binding, worn, or out of adjustment
- low lube level or incorrect (too thick) lubricant
- housing or shafts out of alignment
- too many powershifts (haha)
Gear clash (grinding) during shifting
- clutch not releasing
- synchronizer has worn blocking rings and/or cone surface
- broken blocker rings
- excessive output shaft endplay
- detent springs weak/broken
- gears seizing to main shaft
- input shaft binding to pilot bushing
Differential
Gear noise
- contact pattern out of adjustment
- when turning in either direction
- on accel – drive side pattern incorrect
- on decel – coast side pattern incorrect
- loudest when accelerating – rear pinion bearing
- loudest when decelerating – front pinion bearing
- increases with road speed (not affected by turning)
- when turning right
- when turning left
coming soon: brake diagnosis (its long so give me some time)