[paul_macca]

hi,
I just bought an i30 SR and have a question about the manual transmission. I have driven a few manual cars before and never noticed this with any of them:

As soon as my speed reaches anything over say 20km/h and I have shifted into second gear or higher, I get locked out of first gear and are unable to shift back into first gear until I come to basically a full stop. Is that normal behaviour?

The only couple times its really annoyed me was when I was driving up a steep hill in traffic that slowed down to a crawl - I had no power in second but the bloody car wouldn't let me shift down into first.

If I wanted a car to tell me when I can and can't shift into different gears, wouldn't I have bought an auto!

Thanks

[whitbomb07]

I've noticed this to Paul.

I found sometimes giving it a wiggle left and right in neutral can help. But this is more of a solution for second gear when cold.

I find it rather annoying also.

Regards

Daniel

hi,
I just bought an i30 SR and have a question about the manual transmission. I have driven a few manual cars before and never noticed this with any of them:

As soon as my speed reaches anything over say 20km/h and I have shifted into second gear or higher, I get locked out of first gear and are unable to shift back into first gear until I come to basically a full stop. Is that normal behaviour?

No, certainly not normal but you might not be "locked out" and instead just being balked by the synchromesh.

The synchromesh as its name implies synchronises the speed of a pair of gears prior to meshing them and operates by friction in a manner not unlike a small clutch attached to one gear in each gear pair used for each forward gear.  The effort to activate this mechanism is actually provided by you.  This effort increases whenever the two gears in the gear pairs are spinning at a greatly different speed prior to meshing.  You will easily detect that by downshifting into second (say) at a speed much greater than you would normally where you will find you need to push much more firmly and may even hear the gear spin up if you apply the pressure slowly.  If anyone does this I hasten to add that you should not let the clutch out after changing down at a high speed unless you know what you are doing at this point! 

The synchromesh on a new gearbox is quite stiff until loosened up and because the synchromesh on first gear gets much less use than the other gears it takes the longest to wear-in and as such is nearly always much stiffer to engage than the other gears even after a long time, particularly when on the move.  It gets much less use because when engaging first from a dead stop the synchromesh has virtually nothing to do because both gears will already be synchronised - i.e., both stopped, but still adds some friction to overcome but little compared to that required when downshifting on-the-run and particularly if moving relatively quickly.

I'm sure many will remember when cars didn't have synchromesh on first because it really isn't needed... just like reverse.

I drove more than one car that had no synchromesh on any gear... spoilt now 

On that point, double de-clutching was needed when changing down and can still be used, when you know how, to "assist" the synchros and reduce the shifting effort and the wear on the synchros too.

[Lakes]

Very good explanation pip.
i don't need to go back to first with the diesel the torque will usually pull second if car moving.
my first car and probably the first three or four cars did not have sincro on first gear but neather did the old trucks i learnt to drive on, and the trucks were much harder to move into second gear while moving, but to pss a truck driving test you had to put them into first gear while moving or fail the test.
i used to double shuffle old Holdens that had three on the tree back into first gear on the move. simple, if you are in second gear and moving and want to engauge first.... push foot on clutch push gear shift to neutral, take foot off clutch then give motor a quick rev push foot on clutch pushing it into first gear at the same time as you push your foot on clutch ( ensure you are not reving motor) with the quick rev while in neutral you rev and back off.

[eye30]

It's because the gear shift is cable control. As you use the gears from new the cable can streech.  You may need the dealer to reset tension.

I had this when I had the Accent and found that I was practically stopped before I could shift into 1st while the car was moving.

In the i30 I still have difficulty shifting into 1st while moving, even at slow speed, but if you push and hold the stick where 1st is it will synco up and drop into 1st.

I now only shift into 1st when stopped as I find with the diesel there is enough pull in 2nd, even from practically stop.

It's because the gear shift is cable control. As you use the gears from new the cable can streech.  You may need the dealer to reset tension.

Ok, that makes sense.  Accepting that more pressure needs to be applied to overcome the synchro when moving, a stretched or maladjusted cable might limit the pressure such that selection of first can only occur when stopped - when less pressure is needed.

[Lakes]

Thanks eye, just hope the cable does not break on me! i wonder what the cables service life is?

[eye30]

Thanks eye, just hope the cable does not break on me! i wonder what the cables service life is?

I had cable on my old Acccent and I had that for 7 years.  Cable never broke.

If you look down right side of engine, bewteen engine and battery, you can see the cables attached to the gear box levers.

[paul_macca]

Thanks for the info guys.

By the sounds of things it might get better with a bit of use. I only have 2000kms on the odometer so I'll see if it's improved by it's next service.

[Lakes]

Paul, double shuffle, like 2nd gear to 1st gear ( at a reasonable low speed ) depress cluch, move gear shift to neutral, take foot off clutch give motor a quick short rev, keeping pressure on shift to left to allow for spring loading, push foot on cluch pushing it into first at same time.
when mine was new gearbox was very tight now i have just on 30,000k its nicer, it even now selects reverse more possitively

[bobbyd]

My crdi 5 spd about to clock up 30,000km  Most of which is freeway driving so not a lot of start stop traffic type dirving.  First gear is a bitch to get into from 2nd when cold and until i read these posts i thought it had issues.  I did expect by 30k it would be free-er though.

 Is it worth asking for cable adjustment?

Has anyone tried different gearbox oil or a teflon type additive ?