While cruising around or above 45mph [I could be wrong, never really paid to well attention] If i try to downshift to second from any gear, all I get is a nasty gear grinding noise.
This is normal right? I know around that speed either way i'll already be pretty high up in the RPM range but does the transmission just block off the gear changes as a safety feature?



Or am I just failing in serious magnitudes? Id really love to do some 40~ roll launches in second.

 

Sounds like a synchro issue to me.

 

Are you double clutching and revving to something like 6500 to 7000 rpm? The synchros alone aren't going to do it for you at 45 mph.

Ken

 

put the car in neutral at 45mph, rev the engine to 7500 rpm, then quickly shift to 2nd.

does it still happen?

if it doesnt anymore, then yes, you have been a big bag of fail. if it does still happen, you need your tranny worked on.

 

Since there is such a big difference in your cruising rpm and the rpm in 2nd gear, you are asking too much of the synchros. Blip the throttle to get it close to where it will be in 2nd, then shift. Often referred to as "rev matching". It will save a lot of wear on your transmission and give you better shifts. Conversely, when making a big upshift (skipping a couple of gears, say), let the rpm drop to where they will end up in the higher gear.

 

yeah try rev matching if it does not work then you have a tranny issue for sure

 

if your clutch is down all the way, you shouldn't get grinding.

 

It's important to point out too, that while you can downshift into 2nd at 45mph without grinding for a while, you will quickly wear out your syncros and it will begin to grind.

So yeah, double clutch the downshifts. (clutch needs to be released with the gearshift in neutral, blip throttle, engage clutch, shift into 2nd, release clutch)


PS: Grinding gears is never normal unless you're driving an unsynchronized transmission. Like on an 18 wheeler, much older vehicles, and race cars. Even then it's a sign of you doing it wrong.

 

Thanks guys, rev-matching it worked perfectly. it actually went in really smoothly.

I dont ever downshift into second espicially at anything above 40. Unless im trying to do some simple engine braking but even then i'd go down the gears accordingly so the grinding noise is a scary unneeded thought to settle with. But either way I baby my car, unless im doing my daily 9k run.

Although I havent changed the tranny fluid since I got it from the dealer about 2.5k miles in the odo back. So hopefully switching to something synthetic like Ive read around here [a match between redline or royal purple] will also help me out and keep my gears/synchros nice and pretty.