Hello everyone,
i recently purchased a pre owned Mazda 3 hatchback with a manual transmission in it. its the 2.3l. it has roughly 265,000km or 165,000 miles on the car. when i bought the car it rode pretty nice. i took it through town and onto the highway and went through all the gears and the car seemed like a decent deal. the only thing that i needed according to the guy i purchased the car off of was an alignment and a new set of summer tires. he told me that the transmission was just rebuilt. seemed pretty realistic. after driving roughly 100 miles with the car it started to shake and wobble. i then replaced the rear coils and also the sway bars as they were pretty worn out, bought new tires, and got the alignment done. the car was driving mint again... after about another 50 miles i was getting onto the highway and when i went to shift into 5th gear the car transmission started to grind. i put the clutch in and pulled it back and then it went into 5th gear fine. ive had this same problem happen now enough that im worried about it. some days it goes into 5th fine and others i get a grind out of it and i have to pull it out of fifth and put it back in and it works. im at a loss and also money to spend trying to fix the problem. any ideas of what it could be. to me if it was the syncro then it would happen every time i went to shift into fifth gear. if it was a linkage issue then i would have this same problem going into 1st and 3rd. could be as simple as not enough fluid or is the problem much further than this and i need to basically pull the transmission out and get it worked on. ive contacted the seller and he said his mechanic won't warranty the work as it was a cash deal and the car has since been sold. i don't need negative comments saying how i got scammed or anything, just some guidance as to what the problems may be.

thanks

 

1st step drain the gearbox oil, refill it with Castrol VMX. Drive it for a week or two and report back. Quick cheap fix ( if it works)

 

would you recommend adding any Lucas oil series in with this?

 

@grim_reaper
i changed out my transmission oil today. i got just shy of 3liters out of it and id didn't look all that bad. i went for a drive after and now i have the same problem with first, third and fifth gear now. i sometimes would grind before i changed the oil but mostly just felt like it was in neutral. now it won't grind but 1,3,5 all feel like they are in neutral. when the car is off it feels normal. do you think i just have a broken shift linkage or do you think this transmission is a ticking time bomb?

 

I know for certain the 2009 - 2013 Mazda has adjustment in the shift cables, I assume the 2004-2008 would be the same.

Try making small adjustments to the cables and see what happens.