3rd gear on Series I and II are both POS
 

3rd gear on my series I went out and I replaced it with a series II tranny, and it is better, but 3rd gear on these trannies just aren't that great. Even with a series II you have to pretty good rev matching and you still have to give it some time before the syncro matches. It kinda of disruptive when you are driving on the track to wait for the syncro to match or else you will be damaging things.

143,000 miles (20,000 boosted) on a S1 trans and zero synchro issues. Most people I know who have had issues is because they can't drive stick well or they abuse their trans. My S2 trans is going in tomorrow we shall see how it does.

Learn to drive ;) I've driven mine with over 500hp at the track for over 40 hours last year...and for 8 years N.A.

It's pretty easy to say he's a bad driver without offering any actual help.

Help?....He's had 3rd gear go out on 2 transmissions....think that's got anything to do with the way he is shifting the damn thing ?

everyone beat me to it...Keep practicing. Maybe this time 3rd will last.
If anything, I can see complaining about 2nd gear. It does seem to be the one that most have issues with.

no issues with me, but mines relatively new at 55k

That is not what he said, at all. Read it again.

Totally support this, take a breath and do everything calmly, you'll go faster.

sorry but its really silly to generalize. My 3rd gear is one of the few that DOESNT give me any hint of issues. 2 and 4 are the ones that people seem to complain about the most.

Are members of this forum allowed to be calm and gentle?

Ken

learning to be calm and quick is how you drive fast.

I am still on my series II tranny the 3rd gear hasn't gone out yet. I just grind sometimes going into 3rd.

I think the problem was identify by Hill, the revs don't build up fast enough and I guess a lighter flywheel is going to be on my wish list.

When I hit the corners and downshift into 3rd. I brake and heel toe, I try to get into gear and I sometimes grind it going in. The only way I've been able to avoid it is to brake and stay a bit longer on the gas and wait for the revs to build. But it totally screws up my brake points and the flow I have into the corners. I find it kinda of disruptive. I know the tranny are sensitive and have always been gentle on the shiftier waiting for the syncros to let the shiftier in with enough pressure.

The flywheel won't effect the synchros if the clutch is pushed in, nor will the revs, unless your clutch is dragging.

mine was fine at 55km till i swapped the factory oil out for redline full synthetic MT90 , i then was getting 3rd gear lockout so i took out a quart and added 1x quart of redline MTL for a 50/50 mix as many people recommended . Still get it a bit of lockout but not for as long. no problems shifting after 10 mins or so

My hole trans is POS. (Mostly my falt) need a rebuild or a low milige or both.

The input shaft/layshaft (splined to the gears) and the output shaft (splined to the synchro "dogs") are being synchronized. The synchronizer deals with transmission internals. If the clutch is disengaged (pedal pushed in), the engine revs (by extension the flywheel) should have no effect on the transmission. When the clutch is pushed in, the driven wheels are the only things giving input to the transmission. The synchronizer seeks to bring the gears (and the layshaft) up or down to the wheel speed.

I think we may be having some kind of communication failure here, because I know you're smarter than to suggest that the engine flywheel is still influencing the transmission with the clutch disengaged.

Its the relative difference in speed between the meshing gears that the syncro has to coordinate. The closer they are in speed when you try and shift the less the syncro has to do to match them. When you get off the gas the lighter flywheel will slow down faster and when you get back on it...will speed up quicker. This will change the way the transmission sees the engine

Calm down, clutch completely in, shift, clutch completely out

From time to time I get a little excited and grind. This is because I do not completely engage the clutch, go to shift and grind. Just calm down first. A calm head will always make a better decision.

The transmission does not "see" the engine when the clutch is pushed in! That is the purpose of the clutch.

If you have the clutch depressed the speed of rev drop has no influence on how fast the input side of the transmission spins up or down. There are three velocities in the drive line: crank/flywheel/rotors; input shaft/lay shaft/gears (all meshed); output shaft/synchros/drive shaft/wheels (again meshed).

When the clutch is pushed in, the flywheel and crank no longer effect the input shaft or the output shaft or the synchros. If it did, like you're saying, you would not be able to sit at a stop sign in first gear with the clutch in - the car would be direct drive. Disconnecting the clutch from the flywheel is how we are able to change gears and sit stationary in gear.

LOL...I thought we were talking about shifting when driving ;) I am well aware of the way the transmission works

It doesn't matter if you're stationary or rolling.

So you're talking about the shock load that occurs to the teeth of the synchro and the face of the gear when the clutch is re-engaged after a fast shift? Shouldn't that be dangerous to the teeth of the synchro rather than the cone section that does the synchronizing?


That's completely different. If the clutch is disengaged, the synchros must do work (unlesss you shift insanely slowly), because you no longer have control of the RPM in the gearbox internals while the flywheel is disconnected. If you double clutch or clutchless shift and manually do the input shaft rev matching, then they do not have to work. Getting the car moving with the starter motor is also completely different than using the clutch. You're creating a complete straw man here. The entire issue revolves around the fact that a normal shift does not have any influence from the flywheel while the clutch is disengaged. Going to a double clutch or clutchless shift completely misses the point.

ok, how about just learn how to shift/drive ?

its funny how most people, including those who were/are boosted, track, beat the shit out of their tranny don't have much problems with the said 3rd gear

op might have bad luck, but how about he doesn't know how to drive for shit ?

My first gear synchro is shot can't down shift till under 7mph. 2nd,3rd,and 4th are good 5th is a little crunchy around 6500rpm and 6th is about gone at 45mph it sounds like a old truck and don't clear up till about 55mph and wines like hell decelerating from 130mph down to 70mph. But I feel I've done most of the damage as I couldn't shift the car for crap when I first got it.

sounds normal for 1st gear niteshade..