I always knew 1st into 2nd was hard on most people. Went in no problem but took a bit more effort. Every other gear was effortless and smooth. Reverse would be an issue fully going in sometimes.


However, starting 3 days ago, my gears are grinding... and grinding kinda hard. Almost to the point im scared to shift... 1st into 2nd is still its usual self. However, second into third patiently above 6k rpms grinds like a bitch going into now. Clutch is buried and even with slower shift (real slow) i get the same outcome.

3rd into 4th is fine.

4th into 5th is the most violent of them all for some reason. Grinds hard when going from 4th to 5th and same when going from 6th to 5th. Its scares me because i dont know if im damaging the tranny any more then it may be...


I did some reading on this site and people mention it could be synchro's and/or tranny oil. I currently got the original tranny fluid in from when the car was manufactured in 2003. It has 30k miles on it. I know not many miles, but its OLD OIL. Almost 8 years.


What do you guys think? I wanted to change the tranny oil and differential fluid a few weeks ago but never got around to it. Im going to try the new fluids first and hopefully that helps. If not then what do you think the problem could be if not oil or synchros...?

And what would be better, Royal Purple or Redline?



Thanks in advance.

 

Any opinions at all?

 

Buy a good used tranny

 

If you can't afford a new or rebuilt ones, then you could check your local auto junk yard. Good luck.

 

You should change the gearbox oil (use Redline), but it will not cure your grinding issues.

Being that it came on all of a sudden, rather than progressively getting worse, I'd check the clutch master cylinder, slave cylinder and the fluid line first. Do you notice the pedal having more free play when you first step on it in the morning? You may not be getting the full release, and causing the grind.

How do I know? Mazda rebuilt my gearbox under warranty, and then replaced the gearbox(!) with a new one, and it still produced a grind. All along, I asked them to replace the clutch actuation parts, and when they finally did, the shift action improved dramatically. However, it's still a marginal trans...

Good luck!