Manual transmission RPM and noise?

[Gr8ful]

Hey all,

Why is it that 4,000 rpm in 1st gear makes significantly more noise than 4,000 rpm in say 5th gear? It appears to sound like 1st gear is making the engine rev a lot more than 5th gear but according to the tachometer the rpms are the same for the engine.

It's obvious the 1st gear's gear must spin a great deal faster than the 5th gear's gear considering it is smaller, but is that the cause of the increased rev sound? Also, will cruising at high rpms in a lower gear rather than a higher gear decrease the life of the engine at all or cause more stress/wear on it? Or if not the engine possibly the transmission from more rapidly rotating gears/parts?

Thanks in advance for any information!

 

[epj3]

Because 4k in 5th gear the noise IS the same, but you have the wind noise covering it up that you dont realize.

 

[gbf1lm]

yes the noise comming from the engine is the same but remember that now u have road noise, tire noise, wind noise . . . all thats gone at barley any speed at 1st.

why dont u do this . . . . stick it in 1st, clutch in rev it up, then stick it in 5th, clutch in rev it up

 

[flashinthepan]

!st gear has very Low tranny gearing...4.35, your winding out far more in 1st at 4000 rpms due to the tranny gearing.