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Old Apr 15, 2010 | 12:49 PM
  #1  
luis05gt's Avatar
luis05gt
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Default downshifting

well most of the time i only downshift at a stop but today my buddy wanted to run them from a roll so i tried downshifting into 1st going 15 mph and it didn't want to go in it just grinded like there something wrong with the synchro could it be something is wrong or is 15 mph too fast to drop it in
Old Apr 15, 2010 | 09:28 PM
  #2  
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Hard to say if 15 is too fast. Depends on the car. Some cars will slip into a lower gear at a pretty high speed. I drove a Passat turbo 6 speed. It seemed to be able to engage any gear at any speed.

Some cars will not. Generally steep geared cars and cars with big clutches. Big clutch means heavy disc. So the synchronizer is forcing the disc to ramp up to speed and it doesn't feel like ramping up.

Try throwing a few revs in and see if it goes in.
Old Apr 15, 2010 | 09:38 PM
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first gear with stock gears is good to like 30 or 35 i forget what, 15 is by no means too fast for it. when i downshift to first i give it a good rev to just about redline and it goes in fine. it will have trouble going in if you don't rev it high enough though.
Old Apr 15, 2010 | 09:55 PM
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luis05gt
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first gear with stock gears is good to like 30 or 35 i forget what, 15 is by no means too fast for it. when i downshift to first i give it a good rev to just about redline and it goes in fine. it will have trouble going in if you don't rev it high enough though.
so do you think my syncrho is broke it used to go in at 20 before i had it replaced or could it be anything with my clutch every other gear is fine
Old Apr 16, 2010 | 06:16 AM
  #5  
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Mine wont do it, but I dont care its nice to know that if I screw up it wont let me.
Old Apr 16, 2010 | 04:07 PM
  #6  
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Originally Posted by luis05gt
so do you think my syncrho is broke it used to go in at 20 before i had it replaced or could it be anything with my clutch every other gear is fine
Just try reving it a little. If everything else with the tranny is working fine don't worry about it.
Old Apr 18, 2010 | 02:22 AM
  #7  
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Downshifting can be hard, and trying to downshift into 1st can be very difficult on most transmissions because the ratio requires very rapid changes in gear cluster speed which the synchro can't compensate for fast enough. You either have to slowly downshift into first or learn to heel and toe and rev match going into first.

My TKO 600 will downshift into 1st, though it's a fair bit notchy and hard doing it, but I usually rev match when I downshift most of the time anyway, so that makes it easy.
Old Apr 18, 2010 | 04:21 AM
  #8  
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No problems here and no revving for me
Old Apr 19, 2010 | 04:05 PM
  #9  
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I've never "downshifted' into 1st, I've always been under the impression you weren't suppose to put it down into 1st until you've stopped...
Old Apr 19, 2010 | 04:09 PM
  #10  
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At least with the 2010 v6 manual transmission the book said never downshift into first when above 15mph, could do transmission damage!



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