67mustang302

Most transmissions aren't set up for it, the cluster speed is too high and it abuses the synchros.

luis05gt

thanks for all the info guys

alexyikes00

when im going into first and im already moving..i just tap the gas alittle..and works fine.

marcuskeeler

1st gear doesn't have synchro on it, it's straight cut. That's why it's always harder than the others to go into if the car is rolling [or sometimes even not]. Have you ever tried to put the car into first with the motor off, to stop it rolling when you're working on it for example, it often won't go in at all and you end up putting it in second. It's because the synchro allows the cluster to move when you push for 2nd but with 1st you stand a good chance of the teeth clashing but not rotating into place because there is no chamfer on them.

Changing down into 1st on the roll is considered to be at the very least unnecessary and normally a bad driving technique. In most countries where manual cars are the 'norm', switching into first on the roll is a formal taboo and a test failure point. This is where the nuances and tricks of driving manual in N America are largely overlooked, folk mostly pass their tests in auto's and end up learning manual on their own later.

1st is a gear used for when the most torque is needed, so starting off, hill starts, etc. The gear has to be strong which is why they don't compromise their strength by cutting a synchro into it.

67mustang302

Huh? 1st on most transmissions is not straight cut, it's helical cut. And the gear cluster cut has nothing to do with synchronization. And in most transmissions 1st IS synchronized, otherwise it would clash every time you went into first from any speed other than stop without double clutching. Reverse is often a straight cut that's unsynchronized though.

And as far as shifting into 1st, it completely depends on the transmission and gearing. In most production cars 1st is a start out gear and not needed once you're moving over 5-10mph, but on some cars the way the trans and final drive are geared, 1st is used. If you race on a street course in something with a 5 speed set up for racing you'll find in turns where you go less than 20-30mph you may need to be in 1st. Lamborghinis used to run 5 speed manual boxes with TALL 1st gears and tall final drives, and would top 1st gear at around 60mph.

v braaten

I have a 2004 GT and I downshift into first all the time( comming to a stop or slowing down to a crawl in traffic). I downshift to first even at 30 mph. It's all in the right foot. You don't have to rev to 5000. I usually stomp it to about 3400 and let out the clutch.

Choppa

i never understood why people downshift to stop why not just pull it out of gear then use your brakes to stop that's what they are there for. i feel that downshiftng to stop puts extra strain on the tranny that isn't necessary

its all about rev matching

67mustang302

Because the engine will provide braking force to the drive wheels. Depending on how a car is set up, if the brake bias is accounting for hard downshifting and you brake in N then you have slightly reduced stopping ability. Conversely if the bias is set for braking in N and you downshift hard under heavy braking, you could lock the drive wheels. Besides, you have more control of a car in gear than in N.