Hey going to post several times with a few issues on the 3. When I go in reverse at a high rate of speed it will pop out of reverse, I have to hold it in reverse so it cant do that. If I go slow there is no issue, also sometimes it is difficult to engage reverse and sometimes you think its in gear but it is only halfway, you drive a bit then POP! Any ideas?

2006 Mazda3 1.6L 5-speed

 

I haven't liked reverse from day one, there doesn't appear to be a synchro, so it's always a bit of skill to get it to engage to start with. If the vehicle is not fully stopped for a second before trying to engage reverse, I seem to have more trouble. If moving very slowly it'll engage with a bit of a clunk. Also, when starting to engage the clutch while pushing it into reverse will then pop in easier.
As for popping out, i'd say the teeth are simply worn out - same sort of issue with going forward, synchros wear and end up having the gear wear, then it starts popping out of gear.
They saved $ by having no synchro, not sure what other reasons there are for how they did the design. I only had one other mazda, which did a similar thing, had to stop fully before reverse would engage - or be moving slowly. Though that was an 84 RX7 with over 170k on it, not sure if it was like that from day one or not.

 

Yeah I also noticed it had no synchro, sucks when it pops out I have to slow down to nothing to go again, and I go fast in reverse cause I deliver alot of papers in the morning, have to back up quite a few LONG roads cause you cant turn around at the bottom where the houses are.

 

doing a lot more mileage in reverse looks like the cause to me, surely you wore it more than the typical driver. too bad it's not still under warranty.
By the way, you didn't give a mileage - i'm curious how long it lasted.
As for a fix, I think that needs a trans rebuild (or at least for reverse) to fix the problem. If you do have it fixed, they may be able to grind some of the parts to make the shifter hold reverse in place more firmly, which may keep it from wearing, or popping out so easily in the future.

 

The car has 34,000km on it as of now, bought it used from the Mazda dealer here, the PO was an old guy that died so they took the car back. So 21,000 miles.

 

thanks for the mileage... i'm suprised it would have failed that early, even if you are using reverse a lot.

 

Well I payed attention today, it does not pop out if I either dont go fast, or dont give it too much gas at the start, or dont hit ice to make the tire spin up fast. And by "fast" I mean I am usually going 20kph(12mph)-25(15mph)kph for a long distance, say about 10 seconds at least, longest "driveway" (more like a road) I do this on every morning is about 500ft and there are several that are around this length. If I went any faster I think everyone would complain about the whining noise the tranny makes cause its a straight cut gear.