Towing for newbs: Trailer brakes

Hi guys,

As you may remember I just got a Mazda CX-5. I plan to tow a 1978 Starcraft Starflite 6, which has a dry weight of 1225 lbs. (If it matters, the trailer is only 8 feet long). With minimal gear and just two vehicle occupants we should be well within the 2k lb tow limit of my vehicle. Which brings me to a question (I have not seen this answered in previous threads, and if it has been I apologize in advance!):

In California, a trailer of this size (under 1500 lbs) does does NOT require trailer brakes. However, my Mazda manual says that any trailer over 1000 lbs should have brakes.

My question is, do I really need to add brakes to my trailer? (7 inch hydraulic surge brakes were optional equipment on this trailer originally, so I assume they *could* be installed if I need to do so, but I'm wondering how necessary it is).
 

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No, you do not need trailer brakes at less then 2000 pounds. A surge brake system might be helpful, if it is not too expensive to add. I thought the threshold for trailer brakes was 2000 lbs.

There are a couple of other towing threads on the forums. A CX-5 is a very capable tow vehicle. But towing is serious business and needs patience and a gentle, cautious hand. WEIGH your trailer and ensure you KNOW how to load it so well over 10% of the trailer weight is on the tongue; or, weigh it every trip.
 
Thanks Colt. I just want to make sure I am not going to blow out my transmission or something by not having brakes on a trailer over 1000 lbs! I would like to add them in the future if my trailer is set up for them (which I think it is, but it is currently at my in-law's farm so I am not sure). Since it doesn't have much space folded down I suspect at least half of our gear would be in the car, but I am not sure. Thanks for the tips!
 
I might be overthinking but I was watching a video of a senior chassis engineer explaining the infamous zr2 bent frame. He mentioned the force of the trailer when braking at weird angle might activate the crumble zone. So maybe Mazda limited the weight might be due to same reason. Nonetheless, Mazda will definitely deny responsibility if you don't adhere to the warning.
 
My car is no longer under warranty anyway so I don't expect them to take any responsibility even if something *was* their fault. Good point tho.
 
Thanks Colt. I just want to make sure I am not going to blow out my transmission or something by not having brakes on a trailer over 1000 lbs! I would like to add them in the future if my trailer is set up for them (which I think it is, but it is currently at my in-law's farm so I am not sure). Since it doesn't have much space folded down I suspect at least half of our gear would be in the car, but I am not sure. Thanks for the tips!

I don't think trailer brakes (or not) will affect the transmission. Trans fluid temp is the indicator for trans overload.
 
I might be overthinking but I was watching a video of a senior chassis engineer explaining the infamous zr2 bent frame. He mentioned the force of the trailer when braking at weird angle might activate the crumble zone. So maybe Mazda limited the weight might be due to same reason. Nonetheless, Mazda will definitely deny responsibility if you don't adhere to the warning.

I don't think any of us, including Mazda, expect a CX-5 to tow a trailer through whoops in the desert fast enough to bend the frame in a crumple zone. I'm waay past done with GM products, but I'm sure their frames are stronger then all anticipated (and measured) loads applied. Whatever the cause of the bend, it was something very extreme.

The most likely reason for Mazda's US ratings is one of: liability, SAE towing standard, US law requiring (or not) trailer brakes. We also tend to be Rebels and ignore laws and rules when we see fit.
 
Well I got a couple of estimates to get trailer brakes installed and they range from $800 to over a thousand. I think I will drive the trailer home this weekend (completely flat, 2 hour drive) and see how it does before I make a decision.
 
Well I got a couple of estimates to get trailer brakes installed and they range from $800 to over a thousand. I think I will drive the trailer home this weekend (completely flat, 2 hour drive) and see how it does before I make a decision.
Is that for surge brakes, or trailer brakes and controller for Mazda? I look forward to seeing what you do.
 
The cheapest estimate I got was around $800 for surge brakes. The guy said he would call me back with an estimate for electric and that they might be slightly cheaper, but he never called me back. I suppose I should call him!
 
They sell trailer brakes on eTrailer com. I don't know how hard it would be to figure out what ones would fit and install them. Maybe that's why you haven't heard back.
 
I might be overthinking but I was watching a video of a senior chassis engineer explaining the infamous zr2 bent frame. He mentioned the force of the trailer when braking at weird angle might activate the crumble zone. So maybe Mazda limited the weight might be due to same reason. Nonetheless, Mazda will definitely deny responsibility if you don't adhere to the warning.
Doubtful, overseas towing is 2000KG (over 4000lb) for 2.5/2.0 since 2012
 
Not without trailer brakes.
I'm talking about the crumple comment.. the unbraked limit for AU cx5s for example is 750kg or 1650lb. And who's to say wether that's a brake power consideration, a legal consideration or a chassis.. brakes are nice to have and easy to add, but I I wouldn't stress about ops trailer weight being potentially damaging
 
I'm talking about the crumple comment.. the unbraked limit for AU cx5s for example is 750kg or 1650lb. And who's to say wether that's a brake power consideration, a legal consideration or a chassis.. brakes are nice to have and easy to add, but I I wouldn't stress about ops trailer weight being potentially damaging
Me too. The weight of the trailer would affect how much force it exerts on the car when the car brakes. If the trailer doesn't have brakes, the car has to absorb all of that trailer kinetic energy. If the trailer has brakes (that are activated), those brakes reduce the force on the car from the trailer.
 
AU gets an unbraked trailer weight of 750 kg. We get 2000 lbs. I wonder what our braked rating would be, if we got one. Theirs is 1800 kg, almost 4000 lbs.

 
Update: completed my first tow (i.e. brought my trailer home finally). Towed for about two hours, mostly highway (but also some stop lights), totally flat drive, did just fine (as expected for an easy drive). Only issue I noticed was that my blind spot indicators were lit up for most of the drive, and sometimes were *not* lit up when people passed me. I guess the trailer confuses the sensors or whatever, so that's good to know.
 

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AU gets an unbraked trailer weight of 750 kg. We get 2000 lbs. I wonder what our braked rating would be, if we got one. Theirs is 1800 kg, almost 4000 lbs.

In the US our unbraked weight, at least on the 2nd generation, is 1000lbs, braked is 2000lbs.
 
Mazda's online manual for the 2018s says 2000 lbs for the gas engine and 3500 lbs for the diesel, unbraked. There is no braked rating in the U.S.


The linked 2018 manual has the same instruction as my 2015 manual:

"Trailer Brakes: If the total trailer weight exceeds 450 kg (1,000 lb), trailer brakes are required. If your trailer has brakes, make sure they comply with all federal, state, and local regulations."
 
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