So, every now and then when I start my car up and put it in reverse it grinds. Clutch is all the way in, car isn't moving. My driveway is on a good slant and I have a hurst short throw installed.

Any idea's, ya'll?

 

Mine does the same thing time to time. I wouldn't worry about it too much unless someone else has another opinion.

 

Same here, Mine just started doing it and I am at 8k miles.

 

i had the problem with my ss/sc if u put it in first gear first than reverse it doesnt do it.

 

mine does it once in a while, i have noticed if i slide it into first before reverse it goes in a lil nicer.

^^^haha beat me to it

 

Mine does it once in a while as well.

The Reverse synchro must not be all that great in these transmissions.

If you put it in 1st at a dead stop and then engage R, you won't ever get a grind because putting it in 1st stops the input shaft from turning.

 

no synchro in reverse

 

Got a jeep that does it sometimes, never in the cobalt though.

 

Mine has been doing this a lot lately. I usually bump a forward gear before going into reverse. It's recommended anyway.

 

i put mine in second before going into reverse, and it doesn't grind.

 

According to GM and other sources, the F35 most certainly does have a synchronized reverse.

Engaging any gear will stop the input shaft and allow you to engage reverse without grinding.

 

really? huh.... thought alot of gm tranies had no sync's in reverse, good to know for fact it does.

 

Almost all GM transmissions have synchronized reverse and have had for a while. Everything from the F35 to the T56.

Japanese cars typically don't have syncrhonized reverse. They save money in engineering so that they can give you a nicer texture on the underside of your dash.

 

try pressing in the clutch, and holding it for a few 5-6 seconds, then going into reverse. It shouldn't grind. If you just press it in and go to revers, you can get a good grind. I forgot the reasoning exactly for this, i remember reading it on here 3 years ago about the ss/sc... try it.

 

That just gives the input shaft time to slow down for smoother engagement. Simple as that.

 

and that is exactly it.

 

Actually alot of cars can/will do that. Every one of my manual cars has done that at one point in time. I always get in the habbit of throwing the car in first THEN reverse. Its second nature for me now, and it never grinds

 

Awesome, guys. Thanks for all the input.

 

Yeah mine does that sometimes too, I guess I'll try and putting it in first from now on when sitting over night before putting it in reverse

 

Mine started doing it after I swapped my clutch... didn't really do it before that.

 

Sounds like your clutch is dragging then. Might need a shim on the slave cylinder, or the system needs to be bled some more.

 

Those were my first thoughts. Clutch grabs/releases in the middle of the pedal... and the trick I learned to check for drag didn't work. Doesn't mean that not still the case though.

 

Yup, that's all it is. When you first engage the clutch the input shaft coming from the engine is spinning at close to the same speed as the engine RPM. The synchro that meshes with the reverse gear is probably sitting stationary, or at least moving at a much slower speed. When the synchro and gear come together at different speeds, they'll clash and make noise until they mesh fully and rotate at the same speed.

If you press your clutch pedal and hold it for a few seconds the shafts/gears in your transmission will wind down in speed once they're decoupled from the engine. Once they slow down a bit they mesh with the synchro more smoothly (since the rotating speed difference between the two isn't as large), and typically won't make any noise.

 

Ok mine does this going into 1st sometimes but yes on Reverse too. Usually when its cold. So what I hear is I should push the clutch and wait 5 second before engaging a gear?

 

I usually have to hit 3rd or 4th first then reverse