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Hey guys
When im already moving, and try to put it into 1st, it wont go, its very tough, and if i force it, it sounds like its crunching. ( Say when im slowing down at traffic lights, and i push in clutch when coming to a stop, and put it into first ready to take off ) I have to come to a complete stop, then put into 1st to stop the crunching sound.
Any ideas what might be wrong? thx
Old gearbox with worn syncros. Either get the gearbox refreshed, or stop in 2nd. Then change to 1st. If you are moving use 2nd. Only use 1st if from a standstill.
I had the same issue.
Changing my transmission fluid fixed it for me.
If it still occurs i'd look into gear synchros
How often should i be changing my transmition fluid ?Quote:
Originally Posted by Encor3
every 80,000km going by the book. I do mine every 40,000km cos I only drive on roads
ah k, cos mine was changed about 39, 000 or so KM ago... should i still try replacing my transmition fluid ?Quote:
Originally Posted by shadou
up to you really, are you willing to spend the money on getting it changed over? I think you should change it and see that helps with the 1st gear selection. Cheaper than ripping the box open and replacing syncro's
was just about to say the same thing ;)Quote:
Originally Posted by shadou
Im already taking engine out to start rebuilding in about 2 weeks, which means changing the fluid would be a waist :p
Should i look at changing syncros while im there? Or not... because i'm not too sure it is the syncros yet... hmmm
if you're taking the engine out anyways yeah shoot for it. how much are syncro's anyway?
not too much im hoping :pQuote:
Originally Posted by shadou
you shouldnt really be putting it into first while still moving unless you double clutch.
a) it kills yours synchros very quickly
b) its pointless, youre not going to take off until after you stop, so wait and put it into first when you come to a complete stop
i thought fixing synchros cost like 300 each? ask around. if it is 300 each, you may be better looking for a new box.Quote:
Originally Posted by 1996ek1
Yea i was thinking about the EJ8 gearbox anyway, i heard it had better gear ratios?Quote:
Originally Posted by SeverAMV
Quote:
Originally Posted by Mr_will
I'm not putting it into first, and releasing clutch, i'm holding in the clutch, and just putting it in first so i can be ready to take off
before you start swapping gearboxes, have you tried blipping the throttle in neutral before sticking it in first?
EDIT: double check the output ratios/rev range of both cars before swapping the gearbox. you wouldnt want to buy a gearbox that has close ratios for one car, but ends up being longer for yours.
even when still rolling i dont think puttin it into 1st is gonna work unlessQuote:
Originally Posted by 1996ek1
tap the accelerator while ur clutch is in, then go into first..
blip it..
works for me.
nothing wrong with ur box or synchro's just a driving habbit u gotta pick up imo
mine does the same if im still rolling.. i just keep it in 2nd if im lazy
Quote:
Originally Posted by dupac->
But it wasnt always like this
I bought the car maybe abit over 2 months ago, and for the first month it was fine, then it all of a sudden started, and in a week it just got really bad (at first it was just light crunching, or only crunching on the odd ocassion, now it does it every time)
So something has gone wrong along the line there?
yes i understand that.Quote:
Originally Posted by 1996ek1
do you think having your clutch in magically stops your gearbox from functioning???
the gearbox is STILL spinning, and that is why you are having trouble. the input shaft is going too fast, and your syncro is having to work too hard.
which is exactly what i was saying before...it wears out your syncros very quickly if you do this often.
again, as i said previously...there is NO point. either leave it in second till you get to the lights, or if you need to take off double clutch into first. it is one of the harder double clutchs to do, but it can be done.
i think shifting to 1st when it's over 15 kmh is not really good for the box.
I only shift it to 1st when it's under 10 kmh.
I can't go directly from 2 to 1 without double clutch.
not work:
clutch in
shift 2 - 1 (it won't go in)
work:
clutch in
shift 2 to neutral
clutch out
clutch in
shift neutral to one
clutch out
and another tip: don't rest ur foot on clutch pedal. The clutch will wear out faster.
Use the dead pedal.
I didn't think it did anything to your gearbox if you dont disengage the clutch ( hold it in ) guess i was wrong...
haha, its almost as bad as riding the clutch a tad bit too much. pretty much everything you do will be bad to the gearbox if you're driving a manual. its just a matter of how bad, how much the gearbox can take, and how long it can take it.
i rekon
shift down to 1 only <20 or near 10km/h or less
it mite b ur trying to 'force' it in wen not at the right speed
Lol thats how i do it.Quote:
Originally Posted by mrwillz
When im slowing down in second, and its just before the car starts shuddering because its too slow for second, i clutch in and try to go to 1st (must be under 20km by then) and its too stiff, i MUST be stopped.
Anyway, does this sound like an issue, or its just part of having a manual?
lol it prob was fine for the first month..
but then u kept on doing it..
so its kinda messed up ur synchros i guess..
the more u did it... the more you damaged it..
so nows it more noticeable when going into 1st gear.
just go into first on stand still thats it..
to make it more clear. dont bother if ur still rolling... unless u BLIP the accelerator.. and at the right speed..
but yeah goodluck with it
I don't go into 1st when moving but if need be (say I need the power urgently) then I double clutch it in and goes in without issues
Quote:
Originally Posted by 1996ek1
Have you tried the double clutch?
clutch in
shift 2 to neutral
clutch out
clutch in
shift neutral to one
clutch out
na not enough road left by that time to double clutch... lolQuote:
Originally Posted by twing
I'll just get to stop then 1st from now on.
thx guys
you shouldnt double clutch it back into first unless you need to take off in a bit of a hurry. unless youre bloody good at it, youre very likely to mis-match the revs, which if you continue with on an ongoing basis, will cause significant wear to your syncros also.Quote:
Originally Posted by 1996ek1
the reason your car starts to shudder is, as you probably know, that in 2nd your revs are too low for that gear.
the solution is to start letting the clutch out slowly when that happens, and roll to a stop.
be kind to your gearbox, wait until youve come to a stop, and then a moment, then put it into first. in the long run you will get many more kms out of your box doing it this way
Quote:
Originally Posted by 1996ek1
Iv had to adopt this. Mine has one the same and the gearbox has been little less forgiving than it was to start with. Its probably just worn to the part where its becoming a problem.
1st gear is only to get you moving under high load - you shouldnt ever put it back into 1st while moving. Slow down , stop then put it into 1st.
Are you taking the piss here, or serious? lolQuote:
Originally Posted by sid
Well there is an article on down shifting. And it says somewhere there not to downshift into first.
I'm not acctually going into first, im only putting it in first and still HOLDING in the clutch. Just so yous are clear on that....
Quote:
Originally Posted by 1996ek1
Well, from what i gather it seems your gearbox is struggling to keep it going in second. I drive an auto :( so I'm no expert. But aren't you normally able to stay in second until just before the car stops? If your car starts shuddering in second while still moving at over 4km/h then doesn't this ring warning bells?
But I suggest (once again I'm no expert) that you go to nuetral from second as you are just about to stop. Then either go to first (if completely stopped) or second (if you are still moving slightly) when you need to take off.
At what speed does the car start shuddering in second?
EDIT: I know the issue is with 1st gear... but this could be related.
Shuddering is at very low speed. Like 8km, its just too low for second im pretty sure... nothing wrong there....
Doesnt that mean going down gears, from anygear will ruin the syncros?
Besides, im not releasing clutch... i just dont see how it works....
ok here we go:Quote:
Originally Posted by 1996ek1
(nb all the RPM's are for illustrative purposes, please dont reply saying errr 4000rpm in this gear at this speed is wrong, it doesnt matter)
say youre going 60kmh - in 4th gear, at 2500rpm. you put the clutch in, and change down (when i say change down, i mean leave the clutch OUT and just move the gearstick) from 4th to 3rd. the rpm for 3rd at 60kmh is 3500rpm. therefore your sycnro's have to deal with that 1000rpm difference in order to have a smooth gearchange. they adjust the speed of the input shaft so that the gears are spinning at the same speed when they lock together.
the fact that you have the clutch in is irrelevant, the gearbox still has to do the work.
when you add the clutch into the equation, you can get excessive clutch wear, when the clutch has to adjust the different in flywheel speed to the road speed.
hope this helps
Yea man, that helps a fair bit acctually, thanks for that. (to Mr will)
Leaves me with 1 question
So why is it okay to do it when slowing down, say 4th to 3rd, then 3rd to 2nd, but you just cant do it with 2nd to first? even at real low RPM.
Or is it due to the fact that my syncros are wearing out from being old, and i can only notice it when trying to shift into first gear?
no youre right, in order from harder to easiest changes to double clutch it is 5th-4th, 4th-3rd, 3rd-2nd, 2nd-1st, so you are not alone in thinking that.Quote:
Originally Posted by 1996ek1
this will be a fairly lame explanation, but here you go - it is my understanding that gear ratios are the main difference, but im perfectly willing to stand corrected on this point
- the difference between the ratios gets narrower as you go up the gears, such that in terms of RPM, there is a greater difference between being in 1st and second, compared to 2nd and 3rd, and so on.
as a result, its a bit harder to match the revs because the current input speed, and the required input speed are further apart. since you can only estimate (unless youre damn good at doing maths in your head) chances are you'll get it wrong sometimes and not get a smooth shift
yea thanks for that. This makes more sense to me...
I plan on changing to EJ8 gearbox, and i WONT be doing 2nd - 1st shifts again, untill stopped :p
your first gear's top speed is generally around 60% of your second gear's top speed. ie, 40-70, 50-90, 60-100. so the revs nearly double to synchronise properly.
think of it this way, when you're not on the clutch, you're dealing with the gears, when you're on the clutch, you're dealing with the synchros.
first and second tend to be straight-cut rather than angle-cut, but i think that only makes a difference to the sound of the gear rather than the actual engaging.
when you're rev matching with the throttle blipping, dont try to be spot on with the revs, just go like 100-300 revs higher. when you factor in human reaction time, it ends up being perfect.
This is what synchromesh was developed for.Quote:
Originally Posted by SeverAMV
http://www.bbc.co.uk/h2g2/skins/brunel/images/t.gifhttp://www.bbc.co.uk/h2g2/skins/brunel/images/t.gifConstant-mesh and Synchromesh Gears
yes well thats all very well and good, but the point at issue here is what can we do to minimise the wear on the sychromesh.Quote:
Originally Posted by bennjamin
Try this, when driving you drop into third, then second, now your slowing down ready to put it into first, while in second push the clutch and rest the gear stick into first position but dont force it in too hard, now just hold it there and give it like a double rev (just tap it a bit) to match the gear speeds and it should kind of fall in place into first, try that then report back to HQ.
i can only shift into 1st if im going really slow, and it makes it pretty hard, but i never do it anyway cause i was told by driving instructor its ****ed for the gearbox, you should roll and stop in 2nd apparently
true that
NO. please do NOT follow this advice. all you are doing is getting him to match road and flywheel speed.Quote:
Originally Posted by B18cEG
the whole point, if youd actually READ this thread is that it wont go into first. and it has been explained that this is because it is BAD FOR THE SYCHROS.
all he is going to do by following your advice is screw up his gearbox more.
get your facts straight, when he drops geas the revs will raise when shifted into a lower gear, by revving he will match the flywheel to the correct gear speed, but only try if you can do it in the matter of less that a second to do it properQuote:
Originally Posted by Mr_will
Sigh - downshifting to first while in motion = bad. Don't do it if you value your gearbox. B18cEG: you aren't even describing double-clutching.
you are an idiot.Quote:
Originally Posted by B18cEG
the flywheel speed is not the INPUT SHAFT SPEED which is what is creating the problem here. you obviously have no understanding whatsoever about how a gearbox actually works.
by reving the engine with the clutch out he is only affecting the flywheel speed. in order to change the input shaft speed he needs to be reving the engine in neutral with the clutch out.
the method you describe would fail miserably, because as he has already said, he cant get the gearbox into first easily. try reading next time.
i pity the fool who buys your car/gearbox after you
That's what I was wondering when I read it...Quote:
Originally Posted by Mr_will
How does revving with clutch pressed affect the gear speed?
youre exactly right, it does. when the clutch is in, the engine is not connected to the gearbox. this is something that b18ceg above us has failed to realise, so all along he's been shoving his gearbox in first and destroying his sychro's wondering why doubling clutching is so 'easy', when in fact he has been overworking both the box and the clutch in the meanwhile. sucks to be himQuote:
Originally Posted by Yasakani
I thought B18cEG described rev matching.
So:
clutch in
change to lower gear
blip throttle
clutch out
But I wouldn't rev match to 1st.
To change to 1st and keeping gear box happy, wait till you stop.
End of discussion.
I thought the whole problem was that the OP couldn't even get his gear stick to go into 1st.Quote:
Originally Posted by twing
The problem is that the gears are still spinning under its rotational momentum even after you press your clutch in. You can blip your throttle as much as you like with your clutch in, but that won't have any effect on the gears.
That's how I understand it anyway. Correct me if I'm wrong.
you have not described double clutching. you have described the official 'lets make our gearboxes shit themselves' method.Quote:
Originally Posted by twing
to double clutch:
depress clutch
shift to neutral
release clutch
rev appropriately to match input shaft speed
depress clutch
select lower gear
release cluch.
you are completely correct. at least ONE other person here understands.Quote:
Originally Posted by Yasakani
i didn't know what you guys were fussing bout ,misprint. also notice how i said hold it at first position not put it into first, meaning neutral.and when i said just tap it a bit, i mean just tap it a bit quick, no need to hold it in for longQuote:
Originally Posted by B18cEG
Quote:
Originally Posted by B18cEG
still reread what you quoted and tell us if it makes sense. from what i can see, you're still telling him to force it into first, only double clutch when you're in first (bunny hop anyone?)
just avoid using first altogether, 2nd is fine for times when you cant get into 1st. just ride the clutch a little more.
no im saying hold it at first ready to put it in (for quicker operation)Quote:
Originally Posted by SeverAMV
You just have very bad english there B18cEG...
My advice, when slowing down to a taffic light... down gear to 3rd, then 2nd.. and when its slow enuf.. neutral??.... and when u have to stop then STOP..
if not.. and the car is still rolling, dont matter what speed it is.. as long its less than 30km/hr go back into 2nd gear and GO... easy! Thats how i drive.. take advantage of neutral =]
I didn't try to explain double clutching. What I described was the rev matching during heel toe-ing, which is:Quote:
Originally Posted by Mr_will
clutch in
change to lower gear
rev properly
clutch out
http://www.turnfast.com/tech_driving..._heeltoe.shtml
Rev matching is good for clutch.
Double clutching is good for clutch AND syncro.
When I have time to do it, I will double clutch... but most of the time rev match. ;)
Another good reading related to this topic:
http://forums.nasioc.com/forums/arch.../t-233705.html
http://forums.nasioc.com/forums/showthread.php?t=804223
you guys rev when dropping gears?!
Revmatch when you downshift. If you want to get into first, you need to double clutch. Even on a new car with good synchros, you get a pretty loud bang sound when you put it into 1st from 10-15km/h.
isnt the wear thing reversed?Quote:
Originally Posted by twing
rev matching is bad for clutch and good for synchro as your clutch is engaged fully when you blip the throttle. double clutching is good for both as your clutch isnt engaged fully when you're blipping the throttle?
i try to heel toe rather than double clutch, i havent practiced double clutch much so im a bit slow at it compared to heel toe.
No, rev match is good for clutch. Clutch wear occurs when you are in the process of pressing down or releasing the clutch, not when it is fully released or fully pressed down (unless you have a master/slave cylinder problem). Rev match while pressing the clutch down doesn't do anything for your synchros.Quote:
Originally Posted by SeverAMV
Double clutching is done with the clutch fully released. All it is is a rev match done in neutral with the clutch released just before you shift into 1st. With double clutch, you can get into 1st even when moving at 50km/h and it goes in smoothly without fuss or noise. :)
oh i know about the 1st gear problem, but i never revmatch when going lets say 4th gear to 2nd gear (usually done when slowing down at traffic lights or at round about). i just clutch in and drop gear, and i do it pretty slowly not snap.Quote:
Originally Posted by aaronng
Say you are in 50kmh 4th gear, your rpm will be around 2000 rpm.Quote:
Originally Posted by steve88
When you drop to 2nd gear, your rpm will jump to 3500 rpm. You will get a big jerk because the flywheel (or engine speed) needs to accomodate the faster gear speed. It's bad for the drive train (both clutch and syncro).
So, to make your drivetrain happier you could do either double clutch or rev match... or just slow down from 50 kmh to 20 kmh before changing the gear.
You mentioned about being pretty slow... i hope when you releasing the clutch, it's not like 2-3 seconds slow.
The slower you are, the more time spent on the clutch friction point and the faster the clutch wears off. So releasing the clutch should take less than a second.
nah it takes about 1.5 seconds slow. i think by slow i mean i release softly
and i just realised that when at lights i actually do wait for my speed too drop, i dont just go 50km/h then bam too 2nd gear, i usually put clutch in second and let my car roll until it hits about 20-30km/h
Summary is DONT put back into 1st until STOPPED :)
i thought that was common sense.
yeh i know youd fail your Ps if you do it :S
[ Warning: Internet mechanic in the area. ]
Just wanted to post a few views and get feedback on this.
1) "Mista Bone" on www-d-series.org says he's never seen a synchro worn enough to warrant the term 'worn out'. They do wear, but have a very significant life span.
He also points out that he habitually roughs up (with sandpaper) synchro rings during a tranny rebuild to improve their function and points to the fact that higher grade gear oils (slipery-er EP5) perform worse in our synchro boxes.
GM syncromesh gear fluid is supposedly a good fluid for d16 boxes.
Not that there's anything wrong with Honda, just there's a few reports of good results with it.
There's two versions of the GM syncromesh. You want the non-friction modified.
Pennzoil make the GM synchromesh fluid and market the same thing under their own label. I don't have any more info about this nor local avilability.
Do a search on d-series.com for GM + synchromesh.
2) A more significant issue than the synchros is the gear case shifter fork, which will break if forced too roughly. First gear being the worst gear for this.
3) I agree that heel-toeing and double clutching being perfectly acceptable and a complete stop is not really necessary. On D series boxes with the 0.6 ratio gap between 1st and 2nd, this means quire a few revs.
4) "Yea i was thinking about the EJ8 gearbox anyway, i heard it had better gear ratios?"
1st gear on all D gear boxes is 3.25. 2nd gear can vary, but in the situation of shifting down into 1st, they won't be of any help. It's the huge jump between 3.25 and 1.7-1.9 2nd gear.
IMHO lower closer gear ratios and a lighter flywheel are great for heel-toeing and rev matching but still won't help too much with the 2 to 1 downshift.
Nick.
Na i just meant that i was thinking of the EJ8 box, which means i can get rid of my old box with the worn syncros...
and was just saying i want the EJ8 box because of its close ratios....
Sorry guys but i think you would all agree that this thread has been going on for long enough, At the end of the day i think you either need another gearbox with the desired ratios that you want which you will probarbly need to replace the syncro's anyway, or just replace the syncros in your existing gearbox, dont forget the gear selectors (sleeves) more than likely need replacing also, this i also as important as replacing the syncros since they get very worn. I did a full replacement of 1, 2, 3, 4, 5 syncros and 1/2, 3/4, 5/R selectors, From www.gear-speed.com, costs about $1200-$1400 all up including airmail. Goodluck
yeah....but this thread is more about driving style. and i think its good to continue the discussion. im interested to hear how the thread starter is going now.
Ahh good. No more shifting to 1st before stops :thumbsup:Quote:
Originally Posted by Mr_will
And it got me thinking about my downshifts (this thread). Do most of you heel toe, or double clutch down the gears? (im still relatively new to driving, don't know it all)
Double clutching is entirely unnecessary on the streets. That's why you have synchros. Push the clutch in, pop it in gear and release the clutch is all you have to do.
On the track, heel and toe IS part of effective gear-changing and part of the double-clutch process but TBH, I only double clutch on the track on corners that involve huge rev-matches.
I'd suggest watching the super-taxi (falcodore) series of motorsport, they always do footwell footage of double-clutching (arguably more interesting than the race itself) and you can even see them shift without using the clutch on occasion (entirely doable but not recommended in your daily driver if you want to preserve your gearbox - borrow a friend's car to practice :D ).
hahahahaha thanks mateQuote:
Originally Posted by Setanta