Real world towing with a 1/2 ton

[email protected] · March 4, 2012

Only thing I don't get that everyone keeps saying is about stopping power... Isn't this why trailers have brakes???

Stopping Power? - No not really. Trailers have brakes to apply a certain amount of drag to the trailer, not really stopping power above a few miles per hour.

Ive towed a 28' TT and I set my controller to stop the trailer where my brakes on the trucks are barely working... So I can't see how braking would be any issue.

Most Electric Brake Controllers are set - when the truck/trailer is rolling at about 10 to 15 mph. At that speed if you manually apply the trailer brakes fully - the truck/trailer should come to a slow stop. With just the trailer brakes doing the work - it will take 6 to 10 times the distance to stop the combination truck/trailer - as it would take using the truck and trailer brakes.

I am making this overly simple... just for general discussion purposes.

6000 lb truck

6000 lb trailer

The job of brakes on motor vehicles is to dissipate the kinetic energy of the moving mass, when bringing it to a safe stop within a limited distance.

The engine gets things moving by burring fuel to convert the energy held in the fuel - into heat and then motion. That gets the vehicle moving and keeps it moving. Brakes do the opposite - they use friction to convert kinetic energy {momentum} back into heat - which they must then dissipate into the atmosphere.

The electromagnetic actuated brakes on the trailer are very limited. First they are very small for the weight of the trailer. Compare the small drum brakes on your trailer to the large four wheel disc brakes on a 3/4 ton truck. Secondly the actual pressure that can be applied to the trailer drum brakes is limited to the strength of magnets used - compare that to the pressure your hydraulic brakes on your truck can exert on the pads in the calipers.

Why are trailer brakes so limited? Because they are relatively small, in many cased limited to one of two axles {not always} - - they can only dissipate so much HEAT {energy}. Overload them and they will quickly wear away, overload them too quickly and they will glaze the shoes or exhibit fade.

Say the trailer weights 6000 lbs.

Move that at 15 mph - and you have a kinetic energy load of X.

Move it at 30 mph and you have a kinetic energy load of 4X

Move it at 60 mph and you have a kinetic energy load of 16X

Your trailer brake might stop the trailer from 15 mph in say a city block.. as that gives them time to dissipate the heat, without burning up the linings or warping the drums. Try stopping the trailer from 30 mph in the same distance - and you have 4 times the heat to dissipate. Try it from 60 mph and you will quickly reach brake fade and failure. No trailer brakes do not supply stopping power when the trailer is moving much above 10 to 15 mph.

On the other had - the brakes on the truck are far more massive, can dissipate the heat. They are designed to stop the truck and its load from 30 or 60 mph in a very short distance.

The trailer brakes are designed only to supply a bit of drag on the trailer when stopping the truck/trailer from 30 / 60 mph. Just enough to help keep the trailer behind the truck, as the truck brakes stops the forward motion of both the truck and trailer.

if your trailer has disc brakes - take a look at them - they too are tiny - compared to what is on a truck of the same weight.

FWIW,

Carl B.

music · March 4, 2012

Truck brakes are rated to the GVWR, plus maybe a little more fudge factor. They're not rated to stop the GCWR when towing. Trailer brakes are required over 3k lbs in TN, whether you're towing a 14k lb 5th wheel with a 3500HD, or a 7000 lb trailer with a 1500. Of course, a 3500HD is going to stop a 7k lb trailer quicker, just as a 1500 will stop a popup quicker than a minivan. A 2500HD or 3500HD is overkill for stopping a 5k to 7k lb trailer that has dual axle e-brakes, imho.

My own experience is that a properly configured proportional e-brake controller (not time-based), with well-maintained trailer brakes, works well under all emergency stopping scenarios that I've encountered. I was "less than satisfied" doing the same with a time-based brake controller, since they don't react quickly to emergency braking.

latreille89 · March 5, 2012

I guess all I was trying to say before is that my truck an trailer combo with a controller had no issues stopping, I never had to apply any more pressure to my trucks brakes when pulling than if I was not pulling. The trailer brakes did their job and took on the extra weight of the trailer.

oldschool327 · March 5, 2012

My trailer (Scorpion S 1 ) has 4, 12" drums that if needed can lock all four tires going 55 mph downhill out of denver loaded with three 400 pound quads. Plenty of stopping power if adjusted correctly and managed by a top of the line controller.

oldschool327 · March 5, 2012

2005 Fleetwood Scorpion S 1. (28 ft Hybrid)

3500 dry

6500 loaded

WD hitch

Airride air bags with 60 psi

When the quads are loaded it levels out nicely and only requires about 40 psi to ride smooth.

My previous was a 2006 funfinder xt200 toyhauler and I will take the scorpion over it all day long. Best of both worlds and keeps the toys outside so mama is happy.

TRCM · April 8, 2012

The reason for mentioning the stopping power of the truck, is yes, your trailer has brakes, but what is going to stop you if they dont work ? (blown fuse, connector came apart, grounded wiring etc)

things do happen...........................

music · April 8, 2012

The reason for mentioning the stopping power of the truck, is yes, your trailer has brakes, but what is going to stop you if they dont work ? (blown fuse, connector came apart, grounded wiring etc)

That's true, but it's also true for a 3500HD pulling 12,000+ lbs like folks do all the time. I'd guess that a 1500 w/ 7000 lbs in tow will stop quicker without trailer brakes than a 3500 w/ 12,000 lbs (?). Neither would do very well under those conditions, and neither could handle a steep/long grade for very long. When towing, and especially before going over steep grades, I always check my trailer brakes... and keep an eye on them all the way. It's important to be able to stop w/o the trailer brakes, should they go out. That means driving the right speed/gear for the conditions, and watching the brake system.

Black2011 · April 15, 2012

The reason for mentioning the stopping power of the truck, is yes, your trailer has brakes, but what is going to stop you if they dont work ? (blown fuse, connector came apart, grounded wiring etc)

That's true, but it's also true for a 3500HD pulling 12,000+ lbs like folks do all the time. I'd guess that a 1500 w/ 7000 lbs in tow will stop quicker without trailer brakes than a 3500 w/ 12,000 lbs (?). Neither would do very well under those conditions, and neither could handle a steep/long grade for very long. When towing, and especially before going over steep grades, I always check my trailer brakes... and keep an eye on them all the way. It's important to be able to stop w/o the trailer brakes, should they go out. That means driving the right speed/gear for the conditions, and watching the brake system.

Thats what a pre-trip is for! cheack all lights etc, set trailer brake.

TRCM · April 16, 2012

The reason for mentioning the stopping power of the truck, is yes, your trailer has brakes, but what is going to stop you if they dont work ? (blown fuse, connector came apart, grounded wiring etc)

That's true, but it's also true for a 3500HD pulling 12,000+ lbs like folks do all the time. I'd guess that a 1500 w/ 7000 lbs in tow will stop quicker without trailer brakes than a 3500 w/ 12,000 lbs (?). Neither would do very well under those conditions, and neither could handle a steep/long grade for very long. When towing, and especially before going over steep grades, I always check my trailer brakes... and keep an eye on them all the way. It's important to be able to stop w/o the trailer brakes, should they go out. That means driving the right speed/gear for the conditions, and watching the brake system.

But, a 3500 @ 12k is only 1/2-2/3 the towing limit, a 1500 @ 7k, is 95% the towing limit. Big difference.

And the braking systems on the 2 trucks ia vastly different and a good bit larger on the 3500 (at least they were on my 3500 dodge vs a 1500 dodge).

music · April 16, 2012

But, a 3500 @ 12k is only 1/2-2/3 the towing limit, a 1500 @ 7k, is 95% the towing limit. Big difference.

And the braking systems on the 2 trucks ia vastly different and a good bit larger on the 3500 (at least they were on my 3500 dodge vs a 1500 dodge).

My real point was that the truck brakes are not designed for the tow rating on either, and both require supplemental trailer brakes. The heavier brakes on the HD trucks are designed to stop a good deal more load, but I don't think they're going to stop their full tow rating any better than the 1500 will stop it's rated weight--not by my experience.

The 1500 5.3/3.42/6-spd tow rating is ~ 9000 lbs, so 7/9 = 78%. A 3500HD w/ the 6.0/4.10 is ~13,000 lbs. So... 12/13=92%. We're not really comparing pulling power, though... just stopping. The gas truck has the same brakes as the Dmax, which has a higher tow rating.

TRCM · April 16, 2012

Wow, just checked the ratings in my owners manual...ratings are not what I expected (maybe should have checked first eh ?)

08 1500 5.3/3.73/4 spd/CC 4wd max towing is 7,500

08 3500 6.0/3.73/4 spd/CC 4wd max towing is 9,300 (4.10 = 11,800)

I was basing my previous post on my current truck being rated @ 7500, and my previous truck being rated @ 17500, but my previous truck was a diesel dually 4.10 w/man trans too.

I know the brakes on the 3500 I use to have were more than 50% larger then the same brakes on the 1/2 ton version, and you also have to consider the rest of the braking system as in master cylinder and how it is actuated (vac vs hydroboost).

Me personally, I won't tow anything over 2500 lbs without functioning trailer brakes.

rusty01 · April 16, 2012

Well I got about another month before our TT arives! I guess what I will need to do is just hook up to it and drag it around to see what it does before heading out on the open road. There are some decent hills in our neighborhood with very little traffic so I should be able to get a good feel of how the truck will handle the coach. All I know is I can't wait to go camping!!

John Boelte · June 15, 2012

I've got a 1990 Suburban 1500 that I use to tow my motor boat and sailboat. THe motor boat weighs 2K empty + trailer; probably works out to around 3K all together. I barely notice the boat - no trailer brakes, Burb doesn't care. The sailboat weighs 4300... I've got a dual axle trailer with electric brakes on one axle; I want to add brakes to the second axle. THe Burb definetly notices the sail boat. What I really notice is how much the boat pushes the truck around over big bumps - the front suspension gets a good work out! That's the heaviest trailer combo I've towed. I think over 5K you need a weight distribution hitch; I'm probably over 5K with my set up. Fortunately, I don't too far/often.

I'm trying to get a 2500 Suburban, that should be better.

rusty01 · June 18, 2012

Forgot to update this post! lol The truck does surprisingly well for being a 1/2 ton with over 100k miles. Even on windy days it doesn't seem to wander much, even with passing trucks. I got the brake controller that applies the brakes to the TT while going down steep grades (awsome feature!). The only down fall is going up grade. If I mash the throttle and kick er into 2nd gear it will at least maintain and even slightly increase speed but I try not to beat up on er too bad. If I just ease on the throttle I lose about 15 mph on a decent grade (9%). All in all it pulls OK. I can see where a bigger truck would be nice (and a crew cab no doubt!).

yukon_denali_05 · July 17, 2012

I'm going to be towing a 25 ft airstream trailer which has a dry weight of 6500 lbs and prob with gear and fam we will be at or close to 7500. The trailer has a hemsley weight distribution hitch. I'm towing with my '05 Yukon Denali xl. I've got 14" drilled and slotted rotors on front and rear with hawk pads. And of course I've got a proportional e brake controller. Ive got oem chrime 20" gm rims and cooper zeon LTZs. I'm towing it about 500 miles round trip.

What do you all think?