manual trans

[blacksnapon]

On a 5 speed manual trans, there is a bearing noise in every gear except 4th. What is the most likely cause? 1.) Input shaft bearing(sometimes called a pocket bearing) 2.) center support bearing bad 3.) improper lubricant 4.) all synchronizers except 4th bad.

 

[bowtiehatr]

bad driving lol

 

[mrfixit]

Hmmmm.... 4th is the only gear that represents a 1:1 ratio... improper lube would affect all gears... synchros bad would make shifting hard... The only center support bearing I know of is on the driveshaft...That would be the input shaft bearing making noise. The reason there is no noise when 4th is engaged is that gear is part of the input shaft so there is now a load on the bearing.

 

[Fellro]

there is a bearing where the input shaft turns on the output shaft, which does not spin in 4th only, because it is 1:1 ratio, so it would be the center bearing (you're thinking carrier bearing there, mrfixit)

 

[mrfixit]

carrier bearing is what I have always called it, but modern cars, believe it or not, have named it the center bearing. Volvo does, and audi, too... I seem to recall. You are correct tho in that is what I always called it~!