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Discussion Starter #1
Taking mine in tomorrow for a laundry list of things:

reflash - repeated power loss on 93 and 94 octane, replace leaky coolant hose, seatbelt chime disable, piss-poor keyless entry trunk button, intermittant clutch smell when not slipping clutch - ie stopping after highway cruising, and lastly,

I get a nasty grind if I run up 2nd or 3rd gear to 6k then go to 6th to cruise. I have to hold it on the syncro for a while before I can get a clean shift into 6th when coming from 5500 rpm or more.

Anyone else get the 6th gear grind? Is it just inadequate syncros or do I have a bad unit? I'm not talking about shifting it fast or hard either. 5th-6th shift is generally ok though.
 

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Hrmm, this is beginning to sound worse and worse.
Hopefully our transmissions don't prove to be massive hunks of crap.
Sounds like a lot of people are having synchro issues.

I've only had problems with 2nd and downshifting to 4th at highway speeds.

Mine has been in the shop 2 weeks now getting a new transmission for a failed 2nd gear synchro.
 

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Mine has been in the shop 2 weeks now getting a new transmission for a failed 2nd gear synchro.
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Did they give you a free loaner car and if so, what was it? I wouldn't mind driving an RX8 around for a few weeks - rental cars are sooo much fun!!
 

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Discussion Starter #4
Did they give you a free loaner car and if so, what was it? I wouldn't mind driving an RX8 around for a few weeks - rental cars are sooo much fun!!
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Last time I had my '04 6s serviced, they called the local rent-a-car to have a Chrysler min-van delivered to the dealership for me. It's up to the individual dealership. I doubt they would hand anyone a RX8 as a loaner.
 

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HA! an RX-8 would be nice!
I'm sporting the beast of a Tribute, and it is far from fun :(
Although it is starting to feel fast, and that is a MAJOR problem :p
 

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Could someone explain to me why you would ever go from 2nd/3rd right to 6th? You should have problems considering that the rev matching drops by at least 2 grand per gear so even going from 3rd to 6th you need the engine to stop spinning to match (and that doesn't even account for the final drive ratio issue which I can only assume will make it worse).

If you keep forcing on the gears in that situation, even though its not grinding, you'll wear the synchros out.
 

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Discussion Starter #7
55 mph surface street/country road. Stop sign. Go 0-60 quickly because its fun and that's where the MS6 shines, then cruise at 60-65, which I do in 6th. The drop from 3rd at that point is about 3500 rpm give or take. Also, engine speed should be irrelivant since the clutch is depressed. You only need to wait for the input shaft and clutch disc to slow down.
 

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To test the irrelevance, try this: at 55 mph depress the clutch and put the car into reverse. The irrelevance theory would suggest there will be no consequences. Happy motoring - for a while at least.
 

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Discussion Starter #9
1st. What does 55 MPH have to do with engine speed when the clutch is depressed?
Gear engagement has to do with the ratio of input shaft speed and output shaft speed. When the clutch is depressed, the input shaft is decoupled from the engine. It is the synchro's job to provide friction to allow the shafts to match speeds.

2nd. Since reverse has no synchros and the clutch of course does not decouple the output shaft from the drive shaft, it obviously would be disasterous to shift into reverse at 55 mph, if the shifter were to allow you to try it.

I am just asking the 6th gear synchros to slow the input shaft by 2500 rpm during a shift as well as the other forward gears do. The drop in rpm at 60mph from 3rd to 6th is 2500. The drop from 1st to 2nd at 35mph is a 2200rpm drop and you can shift 1 - 2 plenty quick without any grind.
 

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Could someone explain to me why you would ever go from 2nd/3rd right to 6th? You should have problems considering that the rev matching drops by at least 2 grand per gear so even going from 3rd to 6th you need the engine to stop spinning to match (and that doesn't even account for the final drive ratio issue which I can only assume will make it worse).

If you keep forcing on the gears in that situation, even though its not grinding, you'll wear the synchros out.
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Well I feel that the main reason that anyone gets a car in a manual transmission, other than the fun and speed factors, is so they have more control over the car more than an automatic. I can see the reason to do the 2/3rd to 6th, exactly what steve said. However, I am also sympathetic to your concerns about wear on the syncros. So instead of questioning why someone drives they way they do, I'll offer some adivce. Doing the 2/3rd to 6th shift makes the linkage go (huh) so if you want to do this I would either row through 3rd/4th/ and possibly 5th with the clutch in OR go from 2/3rd to neutral let the tranny chill for a sec, (double clutching optional but recommended) and then go to 6th. Happy motoring :D :drive:

O and if some one wants to try the whole "go into reverse while at highway speeds" (ALAN maybe...j/k) first take out a fat insurance policy and second have a buddy film it so you can post it here and we can laugh as your tranny falls out the bottom of your whip ;)
 

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Well put MS686. And since there is no accounting for some people kids or driving styles (those who can obviously afford a new clutch or tranny on a very regular basis), I say "peace. out." :D
 

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Could someone explain to me why you would ever go from 2nd/3rd right to 6th? You should have problems considering that the rev matching drops by at least 2 grand per gear so even going from 3rd to 6th you need the engine to stop spinning to match (and that doesn't even account for the final drive ratio issue which I can only assume will make it worse).

If you keep forcing on the gears in that situation, even though its not grinding, you'll wear the synchros out.
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???

I've been driving like that for years. When you want to accelerate fast, but only to 100 klicks or so and then go easy after that, that's exactly what you do. I had a 5 speed for a loong time and went from 2nd (that goes up to 100) to 5th all the time. No forcing necessary. I find this to be a strange question from someone who allegedly knows (I'm assuming here) how to drive a 5/6 speed.
 

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???

I've been driving like that for years. When you want to accelerate fast, but only to 100 klicks or so and then go easy after that, that's exactly what you do. I had a 5 speed for a loong time and went from 2nd (that goes up to 100) to 5th all the time. No forcing necessary. I find this to be a strange question from someone who allegedly knows (I'm assuming here) how to drive a 5/6 speed.
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There's no 2 ways about it, the bigger the differences in ratios the more synchro wear you're going to have. The rings are just like a clutch disc, they have the job of accelerating and decelerating the gears when you shift. The bigger the difference in speed the harder they have to work. You might try double-clutching on the upshift if you really want to go from 2nd or 3rd to 6th. That might help a little. I used to drive an old International step van with a crash box 3 speed and the ratio's were so far apart that you had to double-clutch it even on upshifts to keep it from grinding. So it does work. On a downshift, when you dbl-clutch you're accelerating the countershaft to match the new speed, on an upshift you have to slow it down.
 

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Taking mine in tomorrow for a laundry list of things:

reflash - repeated power loss on 93 and 94 octane, replace leaky coolant hose, seatbelt chime disable, piss-poor keyless entry trunk button, intermittant clutch smell when not slipping clutch - ie stopping after highway cruising, and lastly,

I get a nasty grind if I run up 2nd or 3rd gear to 6k then go to 6th to cruise. I have to hold it on the syncro for a while before I can get a clean shift into 6th when coming from 5500 rpm or more.

Anyone else get the 6th gear grind? Is it just inadequate syncros or do I have a bad unit? I'm not talking about shifting it fast or hard either. 5th-6th shift is generally ok though.
[/b]

I did exactly what you described in both second and third...no grind at all -- but as it has been mentioned I too can't imagine this is really how the shifter was designed to be used -- of course this is my completely nontechnical opinion... :D
 

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There's no 2 ways about it, the bigger the differences in ratios the more synchro wear you're going to have. The rings are just like a clutch disc, they have the job of accelerating and decelerating the gears when you shift. The bigger the difference in speed the harder they have to work. You might try double-clutching on the upshift if you really want to go from 2nd or 3rd to 6th. That might help a little. I used to drive an old International step van with a crash box 3 speed and the ratio's were so far apart that you had to double-clutch it even on upshifts to keep it from grinding. So it does work. On a downshift, when you dbl-clutch you're accelerating the countershaft to match the new speed, on an upshift you have to slow it down.
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well, frankly, that's fine with me. That's what the tranny been designed to do, and that's what it's doing. If it wears a little more, so be it. It lasted 13 years with no problems.

plus I don't know what difference in speed you're talking about. After you rev it up to 7k and go to 100kph or so, you let it settle to 3k or so before shifting to 5th... there is no decelerating of gears going on when you match the revs correctly.
 

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well, frankly, that's fine with me. That's what the tranny been designed to do, and that's what it's doing. If it wears a little more, so be it. It lasted 13 years with no problems.

plus I don't know what difference in speed you're talking about. After you rev it up to 7k and go to 100kph or so, you let it settle to 3k or so before shifting to 5th... there is no decelerating of gears going on when you match the revs correctly.
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Yeah, that's true if you let the clutch out in neutral to slow the countershaft, then push the clutch back in again to do the upshift. That's called double clutching. Takes about a hundred times longer to explain the process as it does to actually do it. Just letting the engine rpm's drop without letting the clutch out in neutral when the rpms are what they're going to be when you put it in gear will not slow (or speed up) the countershaft. It's kinda like a turbo impeller, it has the momentum it had when it was spinning at the higher speed and it takes a little time to spin down. If you let the clutch out in neutral it slows it down right NOW.
 

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I get a nasty grind if I run up 2nd or 3rd gear to 6k then go to 6th to cruise. I have to hold it on the syncro for a while before I can get a clean shift into 6th when coming from 5500 rpm or more.[/b]
When you skip shift 3-6, do you row through the gears up to 6th or just go down over and down?
 

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Discussion Starter #18
I go from 3rd straight to 6th. Why wear out the clutch and synchros on 4th and 5th if you aren't going to use that gear just pass through it. Kind of like when I pull up to a stop, I don't down shift through every gear on the way to 1st. Clutches and Synchros cost ALOT more than brake pads to replace. Also, in my experience of rebuilding a few MTX's and from a friend that managed a trans shop for years, the 1st and 2nd synchros tend to wear out long before the top gear synchros.

I also noticed that some MTX have more sychro's on the lower gears than 5th and 6th. I'll have to dig into the specs of ours to see how it's set up.
 
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