Guys and Gals, I wanted to create this thread so that others who are curious can make an informed and safe decision as to their Mazda 3's capabilities to tow something with a hitch. I didn't know what to expect and couldn't find much info on any forum.
Let's get the boring stuff out of the way: I created this thread to inform you not to give you permission. My advice is just my experience. I am at no way responsible for what you choose to tow with your Mazda. I'm just some guy who lives in his Mazda down by the river.....who wants to tow a toy. I don't know if your insurance company will bail on you if you have an accident. I do know that in other markets the Mazda 3 has a tow rating but in Canada it is "not recommended". What you choose to tow and what happens to you while doing it is your problem, not mine.
My Car: 2007 M3 GT 5 Speed Manual 220 000 km
What I tow: 2016 Sea Doo GTR 215. Wet weight with trailer Approx 1000 lbs. I have been towing this for 2 years approx 25 trips now.
Key Points: The machine I am towing is VERY aerodynamic. A Uhaul trailer which weighs less may have a flat front causing a lot more drag. My tongue weight is approx 80lbs and NEVER moves. Almost all the weight is on the trailer wheels and doesn't move around AT ALL in an emergency situation.
ALWAYS think about what the load/forces will be like if you have to hammer the brakes or swerve in traffic at high speeds. I could tow a 3000 lb boat with this car if I was on a 90 kmh flat highway in perfect conditions, but that never happens.
First off, the hitch. I bought the hitch from Canadian Hitches. I was very happy to buy from an Ontario company as it is very rare we get to...no border fees! I installed it myself and it took one hour. It would be easier with two people but it was not a big deal. The wiring took 5 minutes and is plug and play. I was worried my tail lights would blow the fuse supporting trailing lights but in 2 years nothing has happened. Shipping and price were both excellent.
Now to the towing. Remember my car has the 2.3L motor, 5 speed manual, and bigger GT brakes. Personally I wouldn't do this with a first gen 2.0, 4 speed auto, small brakes. Power is NOT a problem. I can tow with the AC cranked and really the only thing I notice is the odd time I have to shift into 4th to make it up a steep hill. I let the revs climb an extra 300 rpm between shifts compared to normal driving. Weight on the rear end is barely noticeable as really a tongue weight of 80lbs is a fraction of the weight our suspension pulled around in the Mazda 5 thing......As for braking, I have the engine brake but I have had to hit the brakes fairly hard twice now and yes distance increased but I never felt unsafe. If you don't tailgate like an Audi in the left lane I wouldn't be concerned. I would say that roughly, a GT with a safe driver can reasonably tow 1200 lbs and not have to pray before every drive. Like I said before remember your load balance and aerodynamics when towing. One of those closed box Uhaul things you may use between apartment rentals, I would never have a combined weight of more then 800lbs.
Boat specific: I travel to a lot of new destinations I never know what the launches will look like. DON'T be concerned. I have had water up to the bottoms of the rear doors...not an issue. I have been on fairly steep gravel ramps questioning if I would be the next YouTube Fail and yanked it right out. The manual transmission is fine. Grab the E brake, rev a little while releasing the clutch, once it grabs just go. My car has 220 000 km on the factory clutch and it grabs like new.
I hope this information helps people. I really don't care if people post "buy a truck or SUV". Most crossovers have the same frame and engine as my car. 0.005% of my annual kms are spent towing and as Jeremy Clarkson once said "walking around in ski boots all year to suit your annual vacation needs is stupid." I can't wait until I get to buy an off lease 3rd gen M3 GT 6sp but mine will be driven until it dies.