Slipping Ist syncro?? Daytona
Slipping Ist syncro?? Daytona
If I go faster than 5 miles/hr and down shift I grind (ouch!!) Ist gear. The car has 20,000 original miles. As a worn 1st synchro is unlikely (in denial ?) I was wondering if 80-90 Sta Lube is too viscous? I have about 1/3 of the clutch left but it grabs well. Someone said there is a gear adjustment for the transaxil. Any ideas? Thanks.
Slipping Ist syncro?? Daytona
The manual recommends SHELL S 1747 A. I have not tried down shifting into 1st when cold. Second gear will grind when the transaxil is warm. Thanks.
Slipping Ist syncro?? Daytona
I mean 1st gear will grind on down shift when the transaxil is at operating temperature. Thanks.
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tyang
Hi Paul,
An old trick for transmissions with non-synchro 1st, and may keep your transaxle from grinding, is to slow the gears down inside the gearbox with 2nd before shifting into 1st. As you coast to a stop, with the clutch pedal depressed, shift into 2nd before putting the selector into 1st. Let me know if this helps. If it does, it will stop the grinding until you figure out what the problem is.
Tom
An old trick for transmissions with non-synchro 1st, and may keep your transaxle from grinding, is to slow the gears down inside the gearbox with 2nd before shifting into 1st. As you coast to a stop, with the clutch pedal depressed, shift into 2nd before putting the selector into 1st. Let me know if this helps. If it does, it will stop the grinding until you figure out what the problem is.
Tom
I have read that Ferrari synchros ...
... do not last long due to the difficulty of changing gear when the gearbox is cold, especially 2nd gear.
Tom's trick should help and is a common thing to have to do. The other thing which will help is to double-declutch. Thus during the gear change and when the gear is in neutral actually let the clutch out and give the engine a blip, and then depress the clutch again and select the next gear. This helps sychronise the gears and is used in racing alot to smooth out the down changes.
Note: that doing this on a synchro'ed gearbox will actually wear the synchros faster (apparently) as the point of the synchro is to grab the output shaft and synchronise the shaft speed. On my Alfa I had to double-declutch to engage 2nd gear from 3rd all the time because the synchro was worn out.
Oil viscosity naturally is important, but as I said earlier I have never read an article that has stated that a Ferrari gear change is easy. You have to be the boss ... others will know alot more than I here.
Pete
Tom's trick should help and is a common thing to have to do. The other thing which will help is to double-declutch. Thus during the gear change and when the gear is in neutral actually let the clutch out and give the engine a blip, and then depress the clutch again and select the next gear. This helps sychronise the gears and is used in racing alot to smooth out the down changes.
Note: that doing this on a synchro'ed gearbox will actually wear the synchros faster (apparently) as the point of the synchro is to grab the output shaft and synchronise the shaft speed. On my Alfa I had to double-declutch to engage 2nd gear from 3rd all the time because the synchro was worn out.
Oil viscosity naturally is important, but as I said earlier I have never read an article that has stated that a Ferrari gear change is easy. You have to be the boss ... others will know alot more than I here.
Pete
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tyang
Hi Pete,
I don't think double clutching will wear your synchros faster. It's to save them.
When I was tracking my 911, downshifts into 2nd after heavy braking required double clutching (heel and toe) if I wanted a nice smooth transition. The synchro could be felt trying to match the speed of the gears if I didn't double clutch. The trick is to match revs. You want to rev the engine to approximately the same speed as the gear you're about to go in, and the shifter will slip right into place. If it's not done right, your shifter hand will feel the resistance. Doing this saves the synchro the work.
Although I've only got a few miles on my Ferrari, it shifts very much like the 911. It's not as vague (thankfully), but neither transmission can be rushed.
In Paul's case blipping will not be needed because he's going so slowly. The transmission will slow to idle speed when he gets it into 2nd. Engaging 1st should be easier.
Tom
I don't think double clutching will wear your synchros faster. It's to save them.
When I was tracking my 911, downshifts into 2nd after heavy braking required double clutching (heel and toe) if I wanted a nice smooth transition. The synchro could be felt trying to match the speed of the gears if I didn't double clutch. The trick is to match revs. You want to rev the engine to approximately the same speed as the gear you're about to go in, and the shifter will slip right into place. If it's not done right, your shifter hand will feel the resistance. Doing this saves the synchro the work.
Although I've only got a few miles on my Ferrari, it shifts very much like the 911. It's not as vague (thankfully), but neither transmission can be rushed.
In Paul's case blipping will not be needed because he's going so slowly. The transmission will slow to idle speed when he gets it into 2nd. Engaging 1st should be easier.
Tom
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Chris Coios
I am not familiar with the transaxle mounting of a Daytona, but perhaps it is like a 275 or 330 with torque tube. I believe there is a thrust reaction rod from the chassis to the bellhousing, parallel to the chassis. If the rubber is in poor condition at either end of the rod or if this is loose or if the transaxle mounts/engine mounts are poor, the transaxle can float relative to the gearshift and can cause difficulty shifting. This would probably result in shifting problems in all gears, however, not just first and second. Any adjustment of the shifter rod, for example should be accompanied by an inspection of the mounts. With the torque tube, the bell housing/engine and transaxle are all fixed together and excessive movement of the assembly relative to the chassis also means movement relative to the shifter!
Chris
Chris
Slow shifting
Too bad Ferrari bought their synchronizer rings from Sindelfingen instead of Muncie or Dearborn!
Deabe
Deabe
Agree Tom,
My [quote]Note: that doing this on a synchro'ed gearbox will actually wear the synchros faster (apparently) as the point of the synchro is to grab the output shaft and synchronise the shaft speed. [/quote]
Tom's [quote]I don't think double clutching will wear your synchros faster. It's to save them. [/quote]
That is why I put apparently in brackets. I have been told this by ... who I cannot remember, but it may be unfounded. I think if you blip or rev too much then the synchro has to work hard to slow the input shaft down to the correct speed ... that is the only reason I can think of that would be detrimental.
Anyway it works very well and is fun so I do it a lot more than I need to.
Pete
ps: Hope the quote stuff works[/quote]
Tom's [quote]I don't think double clutching will wear your synchros faster. It's to save them. [/quote]
That is why I put apparently in brackets. I have been told this by ... who I cannot remember, but it may be unfounded. I think if you blip or rev too much then the synchro has to work hard to slow the input shaft down to the correct speed ... that is the only reason I can think of that would be detrimental.
Anyway it works very well and is fun so I do it a lot more than I need to.
Pete
ps: Hope the quote stuff works[/quote]
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tyang
The Porsche type synchros in the Vintage Ferrari transmission are not horrible, but certainly weaker than other designs. Porsche used them in the 915 transmission until '87, and won a bunch of races with them, so they can't be that bad. What type did they switch to in '87? American Borg Warner type synchros! I wonder when Ferrari changed, and what they are using today?
On the topic of double clutching, sure, if it's done wrong, it will wear the synchros more, but you can really feel the difference when it's done right. It's very Zen-like when you master the several steps it takes to complete a downshift smoothly.
Tom
On the topic of double clutching, sure, if it's done wrong, it will wear the synchros more, but you can really feel the difference when it's done right. It's very Zen-like when you master the several steps it takes to complete a downshift smoothly.
Tom
[quote]double clutching (heel and toe)[/quote]
Double clutching (or double de-clutching) is NOT the same as heel and toe. Double clutching is where you shift the transmission to neutral on a downshift, let the clutch out, blip the throttle to synchronize the ouput shaft of the transmission with the next gear, and then press the clutch again and engage the gear. It is necessary in a non-synchronised transmission to shift that way (or to just not use the clutch at all). Heel and toe is merely where you blip the throttle on each downshift (usually with the side of your foot rather than the heel or toe) to match the engine rpms to the gear you are selecting, to make down-shifting smooth. This does NOTHING for the synchros, but does save wear on the clutch as it does not have to slip at all if you do it properly, and also keeps the engine from giving a sudden increase in the brake bias to the rear wheels.
Double clutching or shifting without the clutch (sliding it out of gear, blipping the throttle and engaging 1st without using the clutch at all, not recommended if you have good working synchros and/or you have no experience in heel/toe shifting) should solve your problems when selecting first, but it really does sound like a synchro problem if it operates anything like the transmissions I'm used to.
On my '77 trans am (I know, not a ferrari, but with an older 4spd synchromesh transmission, and I will have a Ferrari some day), I have to double clutch when it is cold because the synchros take a very long time to synchronise and it will scratch 2nd gear until it warms up. Heel toe is absolutely necessary on down-shifts whenever 'driving angry' and exploiting the rpm potential of the engine as it has such large torque that it will actually lock the rear tires on downshifts if you let the wheels bring the engine up to rpm or even if you don't bring the engine rpm up enough while heel/toe shifting.
Double clutching may lengthen the life of your synchros (at least in theory it should some), but I think the added risk of missing a shift, overreving or shocking the drivetrain may make it moot in a synchronised transmission unless you are good at it. I had my throwout bearing die on me and couldn't fix it for 2 weeks (car was my daily driver at the time) and I had to drive to and from work without using the clutch. I was already decently proficient at heel/toe shifting so I could match the revs properly, but the gearbox failed a couple of months later due to an unrelated problem and when opened the synchros were not in too good of shape.
Double clutching (or double de-clutching) is NOT the same as heel and toe. Double clutching is where you shift the transmission to neutral on a downshift, let the clutch out, blip the throttle to synchronize the ouput shaft of the transmission with the next gear, and then press the clutch again and engage the gear. It is necessary in a non-synchronised transmission to shift that way (or to just not use the clutch at all). Heel and toe is merely where you blip the throttle on each downshift (usually with the side of your foot rather than the heel or toe) to match the engine rpms to the gear you are selecting, to make down-shifting smooth. This does NOTHING for the synchros, but does save wear on the clutch as it does not have to slip at all if you do it properly, and also keeps the engine from giving a sudden increase in the brake bias to the rear wheels.
Double clutching or shifting without the clutch (sliding it out of gear, blipping the throttle and engaging 1st without using the clutch at all, not recommended if you have good working synchros and/or you have no experience in heel/toe shifting) should solve your problems when selecting first, but it really does sound like a synchro problem if it operates anything like the transmissions I'm used to.
On my '77 trans am (I know, not a ferrari, but with an older 4spd synchromesh transmission, and I will have a Ferrari some day), I have to double clutch when it is cold because the synchros take a very long time to synchronise and it will scratch 2nd gear until it warms up. Heel toe is absolutely necessary on down-shifts whenever 'driving angry' and exploiting the rpm potential of the engine as it has such large torque that it will actually lock the rear tires on downshifts if you let the wheels bring the engine up to rpm or even if you don't bring the engine rpm up enough while heel/toe shifting.
Double clutching may lengthen the life of your synchros (at least in theory it should some), but I think the added risk of missing a shift, overreving or shocking the drivetrain may make it moot in a synchronised transmission unless you are good at it. I had my throwout bearing die on me and couldn't fix it for 2 weeks (car was my daily driver at the time) and I had to drive to and from work without using the clutch. I was already decently proficient at heel/toe shifting so I could match the revs properly, but the gearbox failed a couple of months later due to an unrelated problem and when opened the synchros were not in too good of shape.
After re-reading your post, you knew there were different but worded it like it was the same at first. Just wanted to let him know that they were different, and like tom said the goal is to perfectly (or at least very closely) match the revs so that 1st gear is moving at the same speed as your driveshaft when you select it so the (malfunctioning?) synchro doesn't have to do anything. If you are good, you can do it without using the clutch for faster shifts, but if you get it wrong when doing that you risk grinding them a bit and/or wearing the synchros some. Wish we could edit posts as I that took up quite a bit of unneeded space and I don't want to confuse anyone :).
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tyang
I have found many of the posts interesting, especially with regards to “how to manage” Ferrari gearboxes. My humble opinion – based on the size of the gears and the task of synchronizing the clutch disc, the drive shaft, and the large gears in the transmission, the synchros are not really up to the task, specifically in the low ranges where synchronizing also is at the mechanical disadvantage of the gear ratio.
I keep hearing that 2nd gear synchros are week in Ferrari gear boxes. The synchro rings and sliders are all the same size from 5th down to reverse. It isn’t that the 2nd gear synchro is week, it is more that the gear ratio/gear leverage causes the lower gears to have a more difficult task (which is directly proportional to the gear ratio.) The 1st gear synchro will actually have a greater force to overcome than 2nd. The reason we do not normally hear about week 1st gear synchros is that people typically do not dynamically shift to first. Shifting to 1st is more commonly done at the stop sign where everything is static.
The second component in the equation is that for suburban driving, the lower gears are typically “shifted into” more often. Again, first gear engagement is more typically done when the car is stopped and thus realizes less ware.
I rebuilt my gear box a couple of years ago and with 40K miles on the car. The second gear side of the slider was significantly warn, and I had to replace it. I put in 5 new synchros, and swapped the ¾ slider with the 5/reverse slider. (this in on a C4, I assume the reverse slider on the Daytona also actuates 1st.)
Because the synchronizing on a transaxel car, like the Daytona, includes the drive shaft. I can believe that low gear synchronizers are warn.
However, even with brand new sliders and synchro rings, I have to shift slowly into 2nd to avoide the “click” associated with not quit getting the synchronizing job done. This happens regardless of the lubricant, and I have tried many of them.
I have found that if I’m in a hurry and really cram it into 2nd, it works fine – go figure.
I keep hearing that 2nd gear synchros are week in Ferrari gear boxes. The synchro rings and sliders are all the same size from 5th down to reverse. It isn’t that the 2nd gear synchro is week, it is more that the gear ratio/gear leverage causes the lower gears to have a more difficult task (which is directly proportional to the gear ratio.) The 1st gear synchro will actually have a greater force to overcome than 2nd. The reason we do not normally hear about week 1st gear synchros is that people typically do not dynamically shift to first. Shifting to 1st is more commonly done at the stop sign where everything is static.
The second component in the equation is that for suburban driving, the lower gears are typically “shifted into” more often. Again, first gear engagement is more typically done when the car is stopped and thus realizes less ware.
I rebuilt my gear box a couple of years ago and with 40K miles on the car. The second gear side of the slider was significantly warn, and I had to replace it. I put in 5 new synchros, and swapped the ¾ slider with the 5/reverse slider. (this in on a C4, I assume the reverse slider on the Daytona also actuates 1st.)
Because the synchronizing on a transaxel car, like the Daytona, includes the drive shaft. I can believe that low gear synchronizers are warn.
However, even with brand new sliders and synchro rings, I have to shift slowly into 2nd to avoide the “click” associated with not quit getting the synchronizing job done. This happens regardless of the lubricant, and I have tried many of them.
I have found that if I’m in a hurry and really cram it into 2nd, it works fine – go figure.