Grinding noise going from neutral to 5th

LOL, I hear you on the free-rolling feeling of a coasting car. I used to live in an area where I could coast from the top of my driveway, down and up varying hills, and at one point slowing almost to a stop on the crest of the big hill before gravity would get me going once again. I could do this all the way to the nearest gas station several miles away without ever putting the car into gear unless I had accidentally scrubbed too much speed off on one of the corners, or I had a low tire pressure.

I have tried the N-5 shift on nearly all of my other Mazda's from 1980-2003. I found that without revmatching, it is nearly impossible to do the N-5 shift without a nasty sound. I can not say for sure, but your previous experiences doing this on other cars sucessfully might be due to differences in tolerances, design, the angle of the gear cut or depth, etc., etc..

My wife and I were discussing the whole differneces in tolerances issue when we were talking about this problem. Both of us learned how to drive while driving manual transmissions, mine being a Dodge, her's being a Ford. We have both only bought manual transmissions during the 20 years we have been together. The fact is, the mazda has a much smoother and more compact shift mostion than any of the other transmissions we have used. So, long story short, that is probably the whole answer to the issue.


I would vote to try it again, but this time try revmatching the engine to the approx RPM and see how it feels then.

That is exactly what I plan on trying going forward, though I don't plan on doing it anymore than necessary.


Out of curiosity, do you revmatch as you downshift when you are slowing to a stop?(drive2)

No, actually when I am slowing to a stop the car is in neutral while braking, the whole dad chewing on me about not holding the clutch in any longer than necessary thing.
 
No, actually when I am slowing to a stop the car is in neutral while braking, the whole dad chewing on me about not holding the clutch in any longer than necessary thing.

Ok, I know it can be hard to teach an old dog new tricks, but perhaps some revmatching and downshifting is in order?

With todays EFI systems, downshifting while coming to a stop saves more fuel than having the car in neutral with the engine idling. The caveat is that downshifting, while taking some strain and wear off of your brakes, adds a bit more wear to the shifter and clutch. But with proper revmatching, the transmission wear is reduced greatly.

LOL. My grandfather told me the same things as your Dad when I was learning to drive. (yes)
Sounds like your Dad had a few bad experiences with transmissions. I know my grandpa did. Once Grandpa drove his fairly new Rambler back to the dealer in the only gear it would drive in, REVERSE, across town. Mom said they got a lot of stares sitting at the traffic lights. (eek2)
 
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Ok, I know it can be hard to teach an old dog new tricks, but perhaps some revmatching and downshifting is in order?

You are right, and I am trying to put the practice into my general behavior.

With todays EFI systems, downshifting while coming to a stop saves more fuel than having the car in neutral with the engine idling. The caveat is that downshifting, while taking some strain and wear off of your brakes, adds a bit more wear to the shifter and clutch. But with proper revmatching, the transmission wear is reduced greatly.

LOL. My grandfather told me the same things as your Dad when I was learning to drive. (yes)
Sounds like your Dad had a few bad experiences with transmissions. I know my grandpa did. Once Grandpa drove his fairly new Rambler back to the dealer in the only gear it would drive in, REVERSE, across town. Mom said they got a lot of stares sitting at the traffic lights. (eek2)

My dad didn't go that far, but got close. He drove my 85 Mustang GT home for 3 miles through 4 traffic lights using only 5th gear, thank god that 5 litre had great torque!!
 
A lot of reading!

How does the tranny shift if you use it according to our banter?

If it shifts fine, there's nothing to fix.

FWIW... I occasionally get a bit of a synchro mismatch when I try to accelerate quickly and shift from 1st to 2nd. I'm not sure if it's tied to a certain RPM range and the FBW throttle response or not. But that is my suspicion. I seem to have an RPM blip around 4K RPM.
 
A lot of reading!

How does the tranny shift if you use it according to our banter?

If it shifts fine, there's nothing to fix.

FWIW... I occasionally get a bit of a synchro mismatch when I try to accelerate quickly and shift from 1st to 2nd. I'm not sure if it's tied to a certain RPM range and the FBW throttle response or not. But that is my suspicion. I seem to have an RPM blip around 4K RPM.

It does fine if I do the rev match, but I am having a friend who is a mechanic flush the trans to make sure I didn't leave any fun little metal bits floating around in the fluid (eek2) I do appreciate the input :)
 
...B. get a new 5 spd transmission???
Doesn't the Mazda3 have a 6-speed manual transmission? As long as you are replacing the transmission, might as well see if you can get that installed (and if so, how much $$$).
 
The MazdaSpeed3 have 6 speeds transmission, also the the Mazda3 GT with the 2.5L have a 6 speeds transmission. The mazda3 with the 2.3l have the same transmission as our Mazda5.
 
A good start. I think you'll be OK after that. I don't think this tranny was designed for quick shifting anyhow. Your friend will be able to give you the truth. (direct)

It does fine if I do the rev match, but I am having a friend who is a mechanic flush the trans to make sure I didn't leave any fun little metal bits floating around in the fluid (eek2) I do appreciate the input :)
 
Here's my 2 pence: Both my Ford T-Bird SC & my CRX were MT. Both of them had synchro probs after I took ownership of them. What I used to do was rev high when starting from lights, etc, then skip gears. My most usual skip was 4th, but I've skipped from 2nd to 5th, or 1st to 4th, you name it. In only a few thousand miles, I was having major shift probs on both cars. I was even getting locked out of gear sometimes. I am not sure what tranny is in the 90 T-Bird, but being RWD it was either from a 'Stang or truck, so it wasn't a sissy.
So, when I decided I wanted to go MT this time, for longevity (think about all the 300,000 mile cars you have seen - how many were AT?) I knew I needed to change my habits. I now always go in order, except for the downshift when coming to a stop. Hopefully, I am not doing anything wrong anymore & can keep this car for a loooooong time without any tranny worries.

As an aside, the days of coasting are long gone, opus. Power steering is standard, so the engine needs to engaged all the time, 'cuz if it cuts own when coasting, you are SOL on the steering dept. Sure, you are most likely strong enuf to power it, but what happens when the engine stalls, you don't realize it, you're going 65 into a corner & suddenly you have to apply more muscle to make the turn - A. you understeer right off the road or B. you quicky overcorrect & oversteer into a spin & end up off the road. Either way, its not pretty at that speed & the TN troopers would not be happy when called to clean up the mess.
Whatever you decide tho, good luck to ya.
 
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This is an interesting note...

I just added the ground wire to the throttle body, and not only do I have more accurate throttle response, but I have had no issue shifting from 1st to second. (boom07)

Maybe that RPM "blip" was the cause.
 
This is an interesting note...

I just added the ground wire to the throttle body, and not only do I have more accurate throttle response, but I have had no issue shifting from 1st to second. (boom07)

Maybe that RPM "blip" was the cause.

I've heard about this ground wire process before, but have never seen pics of the process. If you happened to either take pics, or could produce a pic guide I would be more than willing to try. Thanks !!
 
i got the same prob on a 2010 M3, just got my car back and they ended up replacing the entire trans. i no longer get the grind from the same scenario.
 
The thread got me into reading 'Auto Mechanics Fundamentals' (M.Stockel)..
A really old book.

Some comments it has about shifting:

=====
"When shifting the transmission, it is wise to hesitate in the neutral range for a brief moment. The synchromesh unit depends upon a limited amount of friction to synchronize the speeds. By hesitating a moment and then shoving the stick smoothly into the desired gear, the synchromesh unit will have time to function.

So called "speed-shifting" is very injurious to the synchromesh gears. and for that matter, the entire drive train. Speed shifting maybe justified when a vehicle is entered in competition. At any other time, it is considered the mark of a poor driving".
========

So I think the original poster was right in that by pushing on the clutch - and give it sometime (for the cluster gears to spin slowly) - one can shift gently into any gear without any grinding. i.e. no need for rev matching. This is true if the car or transmission is new.

But because it is already a habit, one never know how often 'speed shifting' have occured in the past.. and hence damaging the syncrhronizer.
 
Sure the synchros are there to do the job, but the more they have to work, the quicker they wear out. It's that simple.
 
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