Question to P1 and v6 sti gearbox owners (TY754VBAAA)
 

A couple of months ago I have bought a gearbox from WRX JDM which is of identical spec as P1 and sti v6 gearbox (TY754VB4AA, TY754VB5AA, TY754VB6AA). Gearbox spec: 3.166 / 1.882 / 1.296 / 0.972 / 0.738 / 4.444FD
I have a question to all you who have this kind of gearbox in your cars. Is it normal that I hear very gentle whine on 1st and 2nd gears (I am not sure on the 3rd, but for sure I cannot hear it on higher gears). As I said the sound is very gentle, not annoying at all, but it's there, compared to a stock WRX gearbox. The sound is correlated with RPMs.
I have read somewhere theory that these gearboxes emmit this kind of sound because of thicker teeth on lower gears. I wonder if that's true?
I just want to be sure that my gearbox is healthy and it will handle planned power increase :)

Can never remember one whining. You haven't a solid gearbox dog bone mount have you they transmit an awful noise into the bulkhead and would amplify any noise ten fold. Gearboxes due to their nature have the capability to whine but with helical gears you shouldn't hear it.

I did have straight cut FD in my other car and it was much much noisier. Straght cut gears are very noisy. My gearbox is nowhere near that, maybe I should call the sound it emmits "meowing" :)

I had a P1 box in a previous car and it was quiet as a mouse.

2years bump! i have this box and have the same thing but throughout all gears. does a lightedn flywheel make the sound worse? also agree that it seems to go with the rpm. i have heard of straight cut gears and it sounds the same but want a sanity check.(because the sound is driving me nuts!)

Light weight flywheels can be a bit noisy or it could be a bearing on its way out.

thank you! how would we tell one from the other?

Gearbox out and an inspection I'm afraid.

:freak3:

Ty for the help!