Have a hard time reversing. And if it does goes in, it would have this loud grinding noise that doesn't sound too healthy.


Bad syncro? Or need to change tranny fluid? please advise, thanks in advance.

 

Try replacing the shifter bushings. Mazdatrix has a great write-up on how to do this.

 

Shifter bushings would only make it hard to get in gear b/c you'd be searching for the right spot. With practice you wouldn't even notice any more. It probably wouldn't make it grind. But if it won't go in then try releasing and adjusting the position a little as you try again. If that works then it is the bushing.

Otherwise it sounds like a weak synchro. Try applying moderate pressure to push it into gear until it goes in on its own. Avoid forcing it if you can. A good tranny fluid like Neo or Royal Purple may help reduce the grinding somewhat, but I'm guessing you'll just have to live with this until the tranny gets even older, it gets other unrelated problems, or this problem worsens and you finally decide to get rid of the tranny.

 

iirc Reverse has no synchros.

if you can't get it into reverse easily (common problem on FC's) then with the clutch held in, put it in another gear, like second or something and then try reverse again. that always worked for me.

 

Oh ya me too :P. Ya, if it won't go in at all that's one thing, but if you can fiddle with it a bit then push into another gear first before every reverse or its the bushings or etc. I use first gear myself. Might also be the clutch, but then you'd have problems with 1st too. Try the simplest and most likely solution that Raid pointed out before getting too crazy about it.

 

maybe your clutch master and slave are going bad.
That is one sign that they are gunked up...

The rubber inside them melts and clogs the line, doesn't allow fluid to flow through. If this is the problem and not addressed, it could knock syncros out of your tranny.

Rebuild kits are $25 from MazdaTrix.

 

as stated above, I always go into second gear then reverse (keep the clutch pressed down the whole time) - much much smoother.

 

Seconded. If one of those goes, chances are you won't be shifting at all! =)

 

i agree with you guys, but if that were the case, the problem wouldn't be restricted to the reverse gear, it would be happening in all gears.

 

It looks like reverse gear doesn't have a synchro on an NA trans. I wasn't sure, so I checked the parts fiche. There are only 5 synchro rings on page 1D-7 of the S4 fiche, so that means they're only on 1st - 5th. Interestingly, a turbo trans does have a synchro on reverse. It explicitly states it on page 1G-7.

Anyhow, I always had success getting into reverse by pressing the clutch pedal in, and trying again. Since there's no synchro, everything has to be aligned just right for it to go smoothly.

 

if there is air in the hydraulic clutch system from a leak at the master, or slave cylinders or the line then it wouldnt engage the clutch properly so check for leaks if no apparent leaks are found try bleeding the system.

 

I just noticed in the OP's profile it says he has an S4 TII. So that would mean he does have a reverse synchro, and it's probably worn out. Damage to the ring will make it hard to get into gear without it catching.