New trailer--does this sound right--also a tire size question

sailor55330

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Aug 16, 2013
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i am pulling a Cobaltl r3 on a custom Eagle tandem trailer with my 08 Sequoia. I have verified on a cat scale that I am at 5880 lbs with boat trailer and gear. My tongue weight is 9.1% or 540 lbs. all of these numbers are within the limits of the tow vehicle, include hitch, axle, and payload ratings--again using cat scale #s and checked against the trucks manuals. Here's my question--

I had a loaner trailer when I first got the boat as it came with an Eagle custom trailer built for the boat that took 4 weeks to deliver. The loaner trailer was a Yachtclub trailer and pulled with no issues. I got the Eagle today and the tongue is about 2.5-3ft longer. It pulls like crap. It pushed the truck around and porpoises quite a bit, even with airbags. I'm a little confused at this. The one thing about the trailer set up is that the tongue needs to be raised about 1-1.5" to be level which I will correct with a different draw bar. The loaner trailer was the same, but I chose to wait until I had the new trailer as it was towing ok. The truck itself has barely 1 inch of rear sag. Can the extra tongue length be the culprit?

The other factor is after I got the rig home, I was going through the trailer and the tires are wrong. The sticker on the frame calls for 215/75/14. 3 of the tires are 205/75/14. I didn't catch that at the dealer and I will have them correct. I know they got 3 trailers in on the same day and my guess is someone didn't pay enough attention prepping it--interestingly the spare is the right size. I will get them to correct that asap. Could the 1 tire be causing the issues? I know the 215 tire has about 60lbs more carrying capacity per tire. They are load range c. Rainier radials which are hard to find much info on. I'm sure they are not the greatest


Right now I'm pretty disappointed that a custom trailer tows this poorly when an adjustable trailer pulled much better.

Thank you in advance
 

MH Hawker

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the tongue length will change the hitch weight and hat is most likely the problem and yes different tire sise will also do that
 

Groo

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How did you calculate your weight? If you went by just the change in truck rear axle weight, your number is higher than reality, and 9% it a touch low. I always heard go for 10%

I wouldn't want mismatched tires, but it most likely isn't you issue.
 
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ahicks

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Is the winch stand welded in place, or adjustable? What's supporting the transom of the boat? Is it a roller, or do the bunks support it? I'm wondering, because VERY often, moving the winch stand forward or backward 4" can have a pretty dramatic effect on pulling but you want that transom well supported. Proper air pressure in the tires? If you're running the max air pressure as indicated on the sidewalls, and pulling a load that's half of the tires rated capacity, that's going to make the trailer "pull like crap" as well.
 

Thalasso

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Tandem and triple axle trailers only need 5-7% tongue weight. You can reduce your tongue weight by a 100 lbs and still be good
 

sailor55330

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Thanks to all so far. My tongue weight was calculated by getting a scale weight with the trailer hooked to the truck only the truck on the scale, then just the truck. When I subtract, that gets me to 540. Additionally, I weighed just the trailer and then both. All of the math suggests my tongue weight is 540 @ 9.1%. I'm open to other methods but that seems to be the most recommended on many forums

The winch stand is bolted and set so the boat have about 1/2" inch of bunk sticking out from under the transom, so the hull is well supported. My tires are rated at 44lbs max and I was running at 35. With the old trailer that was a good psi, so I started there. My airbags have 29psi and as mentioned that keeps the rear end from sagging more than 1". They are airlift bags with a max pressure of 35psi

As I recall the tow home, I noticed some trailer tire "bounce" even though they are set at 50psi cold, which is the max. I am wondering if these tires have a softer sidewall leading to more up/down oscillation and coupled with the longer tongue is causing issues. I know I am under the magic 10% rule but there seems to be a lot of discrepancy on that for tandem boat trailers, with anywhere from 5-15% being right based on what you read. The difference between 9 and 10% in this case is 40 lbs. I am not saying that this couldn't make a difference, but in 5800lb rig, 40lbs is minimal. I will call Eagle on Monday and see what they recommend for tongue weight. It's not on their web site
 

NYBo

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Reassess after getting proper matching tires and running them at the correct pressure. I wouldn't mess with anything else yet.
 

ahicks

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I'm confused. Are you running your trailer tires at 50psi, or 35psi? If 50psi, there's NO good reason to do that - just as you generally would not run your truck tires at max inflation - unless you were running max load.

Another thought. Is the boat's bow eye secured to the bow stop or is it possible for it to bounce as the trailer frame flexes? If the boat is bouncing, there's a good chance that's your porpoising issue. You may have to do whatever is necessary (depending on trailer design) to minimize/eliminate that issue. A call to Eagle at that point might be a smart move.

If your trailer is anything like the one I had, and running that much tongue weight, that trailer design is going to flex, maybe a bunch with the amount of tongue weight you're talking about. The only way to stop it to secure the hull to it at the bow eye.
 

sailor55330

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Ahicks---trailer tires at 50psi, truck at 35. All that I have read tells me to inflate trailer tires to 50psi cold. Even the dealer had them set to 47.5 which I attribute to a difference in gauges or temp when set originally

Now, I was looking at my trailer again this morning. It is a unique design in that the bow stop is not on the winch but rather lower on the hull. The hull almost rests on the stop instead of against it. The winch strap actually is horizontal to the bow eye and winch with about 20 inches of exposed strap. I had never seen a trailer like that before. I know new trailer winch straps can stretch or need to just be wrapped tighter the first few times. I noticed that I can flex the trailer frame by tightening the winch strap. It's pretty taught and I don't want to go any tighter. I'll see if I can figure out a pic

Update: I have confirmed that Eagle recommends running the trailer at 50psi cold....They also are very vague about tongue weight. The only guideline they offer is to not tow under 5%....other than that.. nothing really.

Anyone else with an Eagle trailer?
 
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ahicks

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Keep reading regarding trailer tire pressure, you'll kill an old wive's tail for your trouble. I generally don't go around spouting qualifications, but I did spend 20 years working on and around trailers for a living...

You adjust the pressure in the trailer tires the same as you would your truck, period! The ONLY reason for running at max, or telling somebody to run at max, would be logic regarding max load - or ignorance. If you know what the boat and trailer weighs, you should be able to lower the pressure to something that corresponds more closely to the actual weight the tires are carrying. You can easily verify the new lower pressure is safe by going on a test ride. Stop after a few miles and put your hand on the tire sidewalls. They should be uniform, and no warmer than your truck tire sidewalls...... You may notice the side running in the sun may be noticeably warmer - just as your truck tires are. If the tires are hot, like you are unable to leave your hand on them for more than a few seconds,THEN you know you don't have enough air in the tires.

From the sounds of it, something needs to change regarding your trailer setup. Would it be possible to run the winch strap under the stop and then up to the bow eye while trailering? Use as is for launching and loading, but rearrange for travel.

I agree we don't want to stress anything, shouldn't have to if it's set up correctly, but if it's allowed to bounce along unsecured - you're going to have that uncomfortable porpoising going on nearly full time. NOT something I'd be looking forward to! -Al
 

sailor55330

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AH--thank you for trying to help me figure this out. I am also open to learning at all times , so feel free to keep throwing ideas! I don't think I'm doing a good job of describing. I have towed trailers for may years and what I feel is not a porpoising motion. It's more of a push/pull almost--no up and down. The bow of the boat rests in a vee that is almost like a cradle and the winch is on an entirely separate post. It is tight and boat is not moving. The flex I was trying to describe is physically the trailer frame. flexing. I can see the frame flex almost 1/2" when I tight and loses the winch strap. I will get a pic tomorrow and try to figure out how to post.
 

89retta

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Does your new trailer have surge brakes ? Perhaps that is what you are feeling push/pull of the actuator sliding . Do you feel it more starting/stopping ?
 

sailor55330

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What I am feeling is definitely not surge brakes. My last trailer had them and I am confident of that. This is happening going down the road at highway speed. The dealer did put new tires on the trailer (Towking STR 2---not the fav, but still new and I will probably change out next spring as we only have about 50 days till storage).

I apologize for the delay in posting this, but here is an image of the bow stop/winch set up. The bowstop is adjustable, but as you can see, there is no bowstop on the winch post. I also looked at the trailer in more detail---the axles are welded, not bolted, so that makes that adjustment pretty difficult and permanent. I want to explore the other options first. I intend to take the trailer out tonight for a test run to see if this has helped. I also think that part of the problem was that the smaller tires had less load capacity, which may have not helped---in other words, they were too small for the trailer.

Anyway, thanks to all who continue to help me work through this... IMG_0865.JPG
 

sailor55330

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Sorry I am just getting back to everyone who is trying to help here. I have had trailers with surge brakes and my issue is absolutely not surge brakes. They are functioning as I would expect.

My dealer did put new matching tires on--Towmax STR 2--not the greatest, but they are all the same size now. I will likely change them early next spring. These tires do have a higher load rating, so that should help some as the previous tires were a little undersized/rated.

I finally have a picture of the bowstop configuration. As you can see, the bow of the boat is not anywhere near the winchpost--nor is there a place for it to rest. The bow rest/cradle is separate and adjustable. The axles are welded, so that is a large undertaking to adjust. I am going to take the trailer for a test run tonight to see if it helped any. The strap that is running down from the bow eye is the safety strap and connects to the trailer itself. I am pretty confident the boat is not moving on the trailer.

I'll update with the outcome of the test tow. Thanks again to everyone.

IMG_0865.JPG
 

jetboater

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Might want to call Eagle Trailers and talk with their technical folks. They make Yacht Club trailers also so they'd be familar with the "loaner" trailer you were using and had no issues with.

They may be able to shed some light on the differences and what things you should check out.
 

sailor55330

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Following up--

So I have towed the boat with the new tires. I also tried tweaking a few things on the set up and have found a set up that seems to be significantly better--

Getting the correct size tires (215 vs 205) has definitely helped. The increased tire load capacity seems to provide a more stable ride with less tire bounce.

Lowering the pressure by about 2 pounds in the tow vehicle airbags has "softened" the suspension just enough to where it does not cause the vehicle to be jarring. I am still at only 3/4" sag in back, so I'm good with that. What I have essentially done is allow the truck's suspension to do more of what it was designed to do.

I inverted the drawbar and now the trailer seems to be more level. This helps as well.

All of this has made the tow much more comfortable and I did not experience any sway at roadspeeds. Additionally, the rig felt solid when braking.

Thanks to all for helped with this.
 

On Holiday

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I have an Eagle trailer with 205 75 14 tires, these were the tires that were on the trailer when I purchased it new, I have since put 2 more sets of tires on the trailer. The sticker on the trailer that lists all the important info on it does say 215 75 14. Haven't had any issues with running 205's. I tow with a 3/4 ton crew cab short bed diesel pickup and keep my speeds between 65 and 70. My new trailer tires now say max speed is 80.
 

sailor55330

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Holiday---how do you like your Eagle trailer. I've only towed a couple of times with mine and I'm mixed on it overall. I don't think the frame is as rigid as the EZLoader I had under my last boat but I have to admit that this trailer loads 1000% easier than the EZloader. I launched & retrieved last weekend for the first time on one of the least favorite ramps I go to. The boat was literally centered with less than 1/4" difference between the chines---yes, I measured! I think I have a brake light with a short in it though which is frustrating on a new trailer. As I said, good with the bad.

Regarding the 205vs 215 tires, what is the weight of your boat?--wondering if that could make a difference-- plus, when the dealer switched the tires out, they put new ones of a different brand all the way around, so it's not an apples to apples comparison as the first time I towed it.
 
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