Do I really need trailer brakes?

[scribeworks]

This looks like a good place to ask a question about "brake controllers." I have a 2009 Mercury Mariner w/3liter 6cyl motor, 4wd, installed tow package that can evidently tow 3500 lbs but something about the electrical relays limits me to 4pin towing harness which excludes a brake controller. Is a brake controller/electrical brakes essential for even the lightest TM models?

Originally Posted by scribeworks

This looks like a good place to ask a question about "brake controllers." I have a 2009 Mercury Mariner w/3liter 6cyl motor, 4wd, installed tow package that can evidently tow 3500 lbs but something about the electrical relays limits me to 4pin towing harness which excludes a brake controller. Is a brake controller/electrical brakes essential for even the lightest TM models?

I personally would not consider towing without a brake controller and trailer brakes for anything larger than a utility trailer (ie: 4'x8'). If you're limited to a 4-pin towing harness, I'd question what class your hitch is and whether it's even up to the job??? Is it a Class II hitch by chance? If so, don't tow a travel trailer with it. They're designed to tow utility trailers, maybe a jet-ski, a quad on a trailer, etc... not a travel trailer.

Those that are towing here with 3500# limits are likely doing so with a Class IV hitch that they've had installed aftermarket with a proper transmission cooler, etc...

Feel free to correct me if I'm wrong, but I believe I'm right...

[Mr. Adventure]

"This looks like a good place to ask a question about "brake controllers." I have a 2009 Mercury Mariner w/3liter 6cyl motor, 4wd, installed tow package that can evidently tow 3500 lbs but something about the electrical relays limits me to 4pin towing harness which excludes a brake controller. Is a brake controller/electrical brakes essential for even the lightest TM models?"

All trailers over 2000 pounds or so need some kind of brakes in most states. All trailers that come with electric brakes need brake controllers (including TrailManors).

The flat four connector is for brake lights, turn signals, flashers, etc, and the way they come from your vehicle pigtail is just fine for a TrailManor. The wire for the brake controller to the trailer brakes and the wire to provide charge 12v power to the trailer are separate, and in many applications, need to be run separately when they are not provided by the manufacturer. In my trailer connector, the MFR's flat four connector actually plugs into the vehicle-end receptacle to provide the signal, brake, and taillight functions. The other 2 wires had to be run from under the dash (one from the hot side of the ignition switch, and the other from the brake controller).

You cannot infer from the wiring harness the tow rating, whether you have the tow package installed, or whether you have the right hitch or hitch receiver, because many vehicles come with or without these items separately from the tow package (including mine). Any competent RV dealer should be able to help you with this.

[Wavery]

It should also be noted that manufacturers ratings are based on a brand new vehicle, with all new components with "zero" wear & tear.

In this respect, the OP should feel comfortable that those are serious numbers if he/she is buying a NEW vehicle.

All too often we have posters, that have a high mileage vehicle, that look at the manufacturer's ratings and think that those ratings apply to their vehicle. Nothing can be farther from the truth.

As a vehicle's components wear, this seriously degrades all of the vehicle's maximum capacity capabilities.

A vehicle with a GCWR of 10,000# when new, may only be capable of safely dealing with half that weight @ 100,000 miles. In some cases, that vehicle should not be towing at all.

Think about all of the individual components that go into the make-up of the vehicle's GCWR........ we are literally talking about thousands of components. Many of those components may be at or past half life. Remember, maximum weight ratings are all based on the "Weakest link" principle. The weakest link (in the case of a high mileage vehicle) may literally be a nut or bolt. It could be something as crazy as old anti-freeze (that could contribute to over-heating) or something as serious as a tired brake caliper assembly. For sure, that "weakest link" changes over time and mileage.

The point being..........ALL weight ratings are subject to deterioration over time and mileage.

Having said all that, I towed our TM2720 the a Chevy S10 ~the same weight & ratings as the Ford Ranger. The vehicle is a bit light for the TM IMHO..... when towing with a lighter TV, it's best to use a WDH. Even then, the 4000# TM is a lot of push on the TV. Trailer brakes are helpful but should not be relied upon to be working when they are needed most. That is why I moved up to a full sized PU.

Just knowing these facts can make towing with the Ford Ranger safer, with appropriate caution. I know that it did with my S10. I just got tired about worrying about it. In retrospect, I wish that I would have skipped towing with the S10 and went directly to the full size truck.

[Mr. Adventure]

Originally Posted by harveyrv

As a vehicle's components wear, this seriously degrades all of the vehicle's maximum capacity capabilities.

A vehicle with a GCWR of 10,000# when new, may only be capable of safely dealing with half that weight @ 100,000 miles. In some cases, that vehicle should not be towing at all.

Yes, the older things get, the closer they get to failures, but that's life. There's no question but that towing introduces durability issues, particularly on the "go" side, as opposed to the "stop" side. But, the brake pads and rotors get replaced on a regular schedule. The wear parts get inspected on a regular schedule. The tires get replaced on a regular schedule. It's just silly to make up numbers like 50% unless you have some hard info that goes with this (how about an NTSB study or an incident report?).

[Wavery]

Originally Posted by Mr. Adventure

Yes, the older things get, the closer they get to failures, but that's life. There's no question but that towing introduces durability issues, particularly on the "go" side, as opposed to the "stop" side. But, the brake pads and rotors get replaced on a regular schedule. The wear parts get inspected on a regular schedule. The tires get replaced on a regular schedule. It's just silly to make up numbers like 50% unless you have some hard info that goes with this (how about an NTSB study or an incident report?).

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"A vehicle with a GCWR of 10,000# when new, may only be capable of safely dealing with half that weight @ 100,000 miles. In some cases, that vehicle should not be towing at all".
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If you are referring to the above statement, I absolutely stand by it. There are a lot of vehicles out there with a 100K miles on it that should not tow anything close to what they were rated to tow new. There are some vehicles with 100K miles that shouldn't tow anything or won't even run, for that matter......I don't need any studies to demonstrate that......that's common sence....I'm not sure what your point is........

Of course, there is everything in between also. It is feasible that a very mechanical owner could actually increase the vehicles ability to handle heavy loads.

However, in almost every case, a vehicle degrades in it's ability to handle the maximum amount that it was rated at new as it ages. However, potential buyers of used vehicles normally use the manufacturers maximum weight ratings as though they were considering a brand new vehicle..........this....is what I am cautioning against. Yes....with regular maintenance, an owner can decrease (or replenish) the amount of wear & tear on the things like brake pads, tires, belts etc. In between those replacement times, those items immediately start to degrade with use. That's why they are referred to as "wear components".

I purposely used the "tired brake caliper assembly" as my example (I have seen trucks and cars with severely over-heated, warped calipers) but I could have just as easily used "Brake fluid" as my example. How many people change their brake fluid?........I would guess, very few. Brake fluid degrades with heat. Anyone that tows a lot (as I do) should replace all of the brake fluid periodically. I replaced all of the brake fluid on my truck when I bought it used (along with all other fluids and wear items).

As I stated, there are literally thousands of individual parts that effect a vehicle's ability to handle weight. In my career as a dealership Service Manager, it has been my experience that MOST owners don't have a clew about maintaining their vehicle, especially when towing or dealing with any heavy loads.

My whole point is, if one is using a TV that is rated (NEW) at or close to what they are currently using it for, they may be over-estimating that vehicles ability. When considering buying a used vehicle, consideration for the fact that more margin for safety should be considered and using the vehicle's NEW weight ratings may be unrealistic.

As a new vehicle ages, an owner should be aware that their vehicle starts degrading those maximum ratings after a very short time.

[Mr. Adventure]

Originally Posted by harveyrv

"A vehicle with a GCWR of 10,000# when new, may only be capable of safely dealing with half that weight @ 100,000 miles. In some cases, that vehicle should not be towing at all"...

If you are referring to the above statement, I absolutely stand by it...

In my career as a dealership Service Manager, it has been my experience that MOST owners don't have a clew about maintaining their vehicle, especially when towing or dealing with any heavy loads...

Harvey,
If tow ratings degraded nearly this much over the ordinary lifespan of a tow vehicle, there would be evidence in the insurance and accident statistics, lots of warnings from the manufacturers, and they wouldn't be missing this as a way to sell new cars and trucks.

I appreciate the possibility that your suggestions about AC capacitors and propane burner orifices offer value to our members. But my experience as a vehicle owner is that car dealer service departments are where they put phony charges in the “40,000 mile service,” make things up when they don't have the answers, and try to scare people into work that isn't needed. This doesn't help your case with me as you “stand by” your story with nothing else standing there with you supporting your position.

This principle never applied to you while you were towing with an old S10?

[Wavery]

Yes.....warped brake rotors are quite common and warped calipers are less common. However, our service dept replaced enough warped brake calipers for me to know that it does happen. It was not a "Scare tactic". It was an extreme example. I could have just as easily used rotors, transmissions, ring & pinions, U-joints, torque converters, broken caliper or suspension bolts...........I just happen to think of calipers because I have seen that on light trucks towing trailers or carrying large campers before.

If anyone is having a problem with the 50% number than maybe you are just trying to find something to argue about......I tried to point out to you that I used the word "MAY"......I thought that you might have missed that but evidently you may not understand the implication of the word.

If a buyer is looking into purchasing a used vehicle with 100K miles on it (to use as a TV), it would be wise for that person to understand that SOME vehicles have been used and abused and an abused, high mileage, vehicle MAY have used up it's capacity to tow by even more than 50%........

A properly maintained and well cared for high mileage vehicle that has not been used for towing before would have much less wear & tear and will have maintained MORE (not all) of it's capacity to be used as a TV.

The point is, EVERYTHING on the vehicle that receives stress degrades over time.....I'm not quite sure what you are taking issue over. If it's semantics....so be it. If you are thinking that things don't stress and brake over time.......then I have news for you......you're wrong. Manufacturers and government agencies have no obligations to worn people that high mileage vehicles may have less capacity than a new vehicle........that's called "Common sense".

As for the S10......I don't have it any longer. It had a 5500# towing capacity (new), which was adequate for the task at hand. It was a great little truck....little truck.....little truck...... It was well cared for and never towed anything or used in any other heavy service but I did not feel comfortable with the short wheel base........what's your point???

Why don't you take this fight offline. It no longer has any relation to the question of the thread.

[Wavery]

Originally Posted by MisterP

Why don't you take this fight offline. It no longer has any relation to the question of the thread.

I disagree........... This discussion is relevant to the issue of any/all TM owners that tow with vehicles that have a 3500# tow rating (as the OP does). It is particularly relevant to anyone that may be considering towing a TM with a 3500# tow rated TV and no trailer brakes. That's what the OP was asking.

I think that it is crucial to understand that most vehicles with a 3500# tow rating should not be towing a fully loaded TM (plus passengers and cargo) at all. Towing without trailer brakes is particularly dangerous (and illegal in most States) and that danger increases as the TV gets older and degrades in maximum ability to handle its GCWR much less, towing over that rating.