# Electric Trailer Brakes and Tires Condition Questions



## DIYguy2000 (Nov 4, 2009)

We bought a used 2001 tent trailer and the tires look like they're in need of replacement. The tread is nearly worn down in spots, and there is some cracking occurring between the treads running length-wise along the tire. Is this an obvious sign to replace them?

I also want to check the electric brakes on the trailer to make sure they're working properly. What is the best way to inspect them or get them ready before we head out on our first camping trip? I don't know if the previous owner used the brakes or not, so I don't want to run into any surprises of the brakes seizing up or something.

Also, the tires are currently rated at 1045lbs @80psi.

The trailer specs are:
GVWR (Gross Vehicle Weight Rating): 2240 lbs
GAWR (Gross Axle Weight Rating): 2090 lbs
CCC (Cargo Carrying Capacity): 439 lbs + 83 lbs water

Is it normal for the tires to be rated to equal the GAWR (1045 x 2 = 2090 lbs)? Or should I replace with tires rated for a greater weight as a safety factor?

Does this mean that the "dry" weight of the trailer is 2240 lbs - 439 lbs - 83 lbs = 1,718lbs?

We're towing with a 2008 Grand Caravan 3.3L that did not come with the factory tow package. I'm installing a Class III hitch with 7-pin wiring harness and brake controller. I'm also installing a transmission cooler.

Thanks for the help!


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## Billy_Bob (Sep 11, 2008)

My trailer brake controller has a switch on the side that I can press and it applies full braking to the trailer.

So I get on a dirt or gravel road, drive slowly, then press that switch. And go a few feet and stop. Then get out and see that both tires on the trailer locked up and I can see the skid marks on the gravel or dirt. Then I see that BOTH trailer brakes are working.

And then I do the same on a paved road. Just applying the trailer brakes will stop the vehicle. If one trailer brake is braking more than the other, then the trailer will swing to one side. If equal braking, then the trailer will stay in a straight line with the car/truck.

My trailer brakes need to be adjusted manually (for wear of the brake pads). There is a procedure for this. Here is a Dexter trailer brake service manual. Find your type of brakes in the manual if this is what you have...
http://dexteraxle.com/i/u/6149609/f/6-8K_Service_Manual_1-12/600-8K_Complete_Service_Manual_1-12.pdf

So far as adjusting the brakes electrically on the controller, read the brake controller manual.

As to tires, I would replace them. Tires can also go bad just sitting in the sun! Ask at a good tire store about weights and so forth. They are the experts!


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## joecaption (Nov 30, 2011)

I also would pull the wheels and repack the wheel bearings.
Not sure how your state works but we have to have any trailers with brakes inspected, just like your car.


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## Billy_Bob (Sep 11, 2008)

As for trailer wheel bearing grease, the manufacturer of my axle recommends a *specific* type/rating of grease. That is because those wheels can get to be quite hot - the grease needs to stand up to the heat.

I asked for that grease at an auto parts store. The idiot working there said they did not have it, but "any" bearing grease would do! I went elsewhere and found the right grease.

Anyway manufacturers specify these things for a reason.

Note: If I am going down a very long downhill road, like in the mountains, I will stop every so often and feel the wheels of my truck and the wheels of the trailer. Sometimes one or the other will be too hot, then I adjust the trailer brakes to take more or less of the braking load.


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## Mort (Nov 26, 2008)

As for the tires: It sounds like your tread is separating, which means you'd better replace them before you drive it anywhere. They will blow out sooner rather than later. You're probably fine with replacing them with the same load rating, you just don't want to go under your GAWR.


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## DIYguy2000 (Nov 4, 2009)

So, everything installed perfectly, well, except for the transmission cooler, that's next weekend's project.

I have priced out the tires and most places only carry them with the rim included, so I'll have to keep looking.

I towed it around our small town just to get a feel for it. I won't take it any further until I get the tires changed. It's getting harder and harder to find a dirt road around here. Couldn't find one, so I tried applying the trailer brakes to full on asphalt using the slider switch. It slowed the van down, but I was expecting the trailer tires to lock up or at least slow the van down much faster than it did. I will have to inspect the brakes to make sure both are functioning properly and go find a dirt road.

I got the brake controller adjusted fairly decently for normal driving conditions and made a few pointers on when to adjust the brake controller for certain situations.

I found it odd on a 'rolling stop' that the trailer jerked when trying to get going again, but realized quickly that as I let up on my van brake the van wanted to roll forward, but the trailer brakes were still on until I fully released my foot from the brake. Guess I'll have to make full stops if I don't want that to happen. Such is life with a time delayed brake controller.

All in all, good experience with the installation of all the towing components and towing the trailer for the first time.


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## Bondo (Dec 8, 2007)

> I found it odd on a 'rolling stop' that the trailer jerked when trying to get going again, but realized quickly that as I let up on my van brake the van wanted to roll forward,* but the trailer brakes were still on until I fully released my foot from the brake.* Guess I'll have to make full stops if I don't want that to happen. Such is life with a time delayed brake controller.


Ayuh,.... that's because the trailer brakes are controlled by the van's brake Light circuit...


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## DIYguy2000 (Nov 4, 2009)

Yeah, it will take some getting used to the time delayed brake controller (hooked up to brake light). Other option would be to use a proportional brake controller, but it's not worth it for towing this light of trailer.

Thank goodness for eTrailer.com's youtube videos for the installations. I spliced into the brake light wire going only by their colour description on their video. It worked fine. Probably should have tested the wire first, but I trust them.


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## DIYguy2000 (Nov 4, 2009)

Just ran into another question that maybe someone here can help out with. I installed a 20 amp auto reset circuit breaker between the battery and the brake controller as per the how-to videos supplied by e-trailer: http://www.etrailer.com/tv-brake-controller-install-2008-dodge-grand-caravan.aspx

I was just reading the manual for the brake controller (Draw-Tite Activator III) and it says to use a 30 amp auto reset circuit breaker: http://www.draw-tite.com/content/downloads/installation/N5520.pdf

I'm leaning to believe the brake controller manual and should switch the circuit breaker.

Anyone have any comments on what circuit breaker should be used for this brake controller?


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## joecaption (Nov 30, 2011)

Just do what the manufacturer suggested, not some generic video.


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## DIYguy2000 (Nov 4, 2009)

Just received an e-mail back from Draw-Tite, they said:

"When using a trailer with just 2 or 4 brakes, a 20 amp circuit breaker works  just fine. When 6 or 8 brakes are on the trailer we use the 30 amp circuit breaker. As the 5500 and 5520 units are rated for up to 8 brakes, we suggest the 30 amp circuit breaker in the instructions. As long as you have only up to 4 brakes (2 axles) the 20 amp is fine."

Thanks Draw-Tite! Helpful again.

As my trailer only has 2 brakes, I'll leave the 20 amp in place.


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