Napboy

Is anyone getting this? Whenever I downshift from 6th to 5th, I get a gear grind before it pops into gear. This, of course, happens at freeway speeds. It doesn't happen when shifting from 4th to 5th. Any thoughts?

Lensman

You ARE pushing the clutch pedal down right?! (Sorry: couldn't resist it )

Cylo

No grinding here.

eccles

Nor here.

lefuton

i've never heard a grind from 6th ->5th, only from 3rd->2nd when i mis-time the rev match and i'm more than 1200-1500 rpm off where i should have been.

santino

i got that gear grind just today...but it was probably due to the fact that i was too excited driving the car.

it only happened once!

santino

wakeech

yea, napboy, if you slow down and let the synchros work it doesn't happen.

Napboy

yeah, but what fun is that? and if i'm cruising along on the freeway and have to downshift to pass, i'm expected to wait for the synchros to catch up before i shift. that's ridiculous.

zoom44

no grind here. had to doan emergency lane change on sunday when a tractor trailer decide it could occupy the same space as my car.i was in the right lane doing about 80 in 6th had to move over to the right which was a lane that was exiting. i blew the horn at him as i was moving hit the brakes a little to get behind the truck shifted down to 5th went back left and then into the far left lane doing about 90 as i passed him. no fuss at all from the car. :D

Napboy

i think i gotta go get this checked out at the dealer.

wakeech

uh, dude, the synchros are like mini-clutches on the gears: if you just try to mash the gear into place without rev matching you're just going to wear out your gearbox in no time flat. if you want to "shift faster", you have to rev match (which may still not be as quick).

Napboy

I'm not downshifting any faster than I would in any other gear and I'm certainly not mashing. It's true that if I pause for a moment in between gears that it won't grind, but I just don't think the synchros in my car are working as well as they should downshifting to 5th gear. If I downshift from 6th to 4th quickly, it's as smooth as silk.

rx7aggie

by rev matching you mean double clutching. if you simply just "wait" while the car is out of gear between 6th and 5th, then those gears (and the input shaft to the transmission) will eventually slow down to 0 rpm, which will make the synchros work even more. if you really want to help the transmission, you have to engage the clutch, rev the engine to match the expected rpm in that gear, and shift into the gear (double clutching).

however, this is not necessary, afterall, that is what synchro's are for. you shouldn't be getting a grind. i never get a grind going from 5th to 4th in my '87 TII, and i have 189K on my car :D

in my haste to make a freeway pass, i've even accidentally power shifted (shifting with closed throttle, no clutch) with very little grind going from 5th to 4th.

talk to the dealer mechanic, take him for a ride and see if it will do it...(it will probably work fine with him in the car; Murphy's law)

blizz81

I thought synchros for the most part should make rev-matching unnecessary to avoid grinding going into a gear. For four years in different cars I have downshifted by blipping the throttle directly after selecting the new gear for a smoother shift, but not to enter the gear...I don't crunch at all. I saw the two m/t cars I've owned in that time go over 100k without any tranny problems, so I wouldn't say any wear by actually making the synchros do their job would be cause for horrible alarm.

But these cars did not have throws as short as the 8. Since other people don't have the problem I might get it looked at. How often does it happen?

Napboy

it happens about half the time shifting from 6th to 5th.

SPDFRK

If it's half the time you definately need to adjust your driving style or there is something wrong. On my car fifth is not as smooth as the other selections, I have shifted a couple times now both up and down and got a little grind but only because I'm being a little quick on the clutch or shifting lazily. No problems in any other gears or during any spirited driving though.

RPIRX-8

This thread is in direct relation to this thread.

I started to experience the same exact issue about 2 weeks ago. It has gotten progressively worse. The issue occurs when performing a quick downshift from 6th to 5th gear. At some times I can't even get the the shifter into 5th because of the grind, sometimes there is a little grind but the shifter eventually slides in without having to go to neutral first.

I decided to take my 8 into my local dealership to have them look at it. They gave me a tech and I took him for a ride. I got up to highway speed and let him do a quick downshift from 6th to 5th. He felt the grind, but in his words wasn't sure if the shift was just to fast (therefore making the behavior normal) or if it was an issue. After returning to the dealership he called Mazda NA tech assist line. Mazda NA tech assist stated they have never heard of or received any complaints on this particular issue.

SO........

They are going to send out a rep to take a drive with me (first me driving then the rep) to take a look at my car and feel the grind. I'm not sure of what the outcome will be, but I wanted to start a thread to see if anyone else has experienced it. I will be posting updates as progress is made. Hopefully the rep will be stopping by within the next week or two.

Ned M

iTrader: (2)

No help from this corner, but suggest you reinstall your OE shift **** before the Mazda rep sees it. You never know what the'll try to pin the cause on.

DisneyDestroyer

I frequently get grinding when I'm in the red zone and try to upshift. This happens 1->2, 2->3, 3->4.

RPIRX-8

DisneyDestroyer,

You might want to take your 8 in and get the clutch checked. I know of some folks who've had theirs replaced around 7000 miles becuase of defect. You definitely shouldn't be getting any grinding during an upshift.

TownDrunk

I remember in a car once upon a time I had a grinding 2->3rd upshift. It turned out to be a failed synchro. If I shifted really slow and let the lever fall into place there was no grind, but shifting quickly, or even at a more normal speed it would grind.

I imagine it would have cost quite a bit to get it fixed, but I got rid of the car soon after the problem reared its head.

I don't know if this is the same problem you have, but it sounded familiar when I read it.

I haven't had any problems with my '8.

DisneyDestroyer

Interesting, I'll talk to the dealers at my next appointment. Fortunately it only happens when the "from" gear is beeping (9k+ RPM), so I can make changes at 8500 and still be OK.

Kathy Atkins

I also get a *bit* of grind when I upshift quickly from 2 to 3. It's kinda bumming me out, cause it's not pronounced enough to be a clear warranty issue, it's just bad enough to tarnish the joy of the 8. My '88 Supra also had a bit of syncro grind when downshifting into 1st, and I had a buddy whose Jeep did this quite badly into 2nd. I'm surprised there aren't many people reporting this. I notice it gets better when the tranny is warmed up, which takes about 20 minutes of driving (quite a bit of warming).

paradigm

This thread's a bit on the old side, but I reciently started having the same issue. If try to do a downshift into 5th from 6th at highway speeds it grinds a bit unless I double clutch/rev match or I shift really slowly.

Rock-8

I actually was just going to post on shifting issues, until I read this thread. My main problem seems to be, shifting quickly from 2nd-3rd, or from 3rd-5th, ... It just doesn't seem that smooth, I almost have to force it a bit... anyone get this?
thanks.