acdii

I have 20 pounds payload left when hitched and loaded.

Too many variances on how much fender drop one should have. One OM said return to stock, one hitch said return to stock, while another said split the difference. The difference between sprung and unsprung is so minor at the front, that I am leaving it as is. I already know what happens if I move too much forward, and what happens if not enough. Right now it is the closest it will get to being on the money. Can't lighten, can't tighten. It's identical to how it was setup on the 14 as far as distribution.

Once I decide on which hitch I am getting, then we shall see where it falls.

mountaintruck

Couple of question for you @Simnut (or anyone else that wants to chime in):

I have been following this thread and am considering a set of Sumos next spring as an upgrade to my towing set up. I tow a 6000lb (thats fully loaded, usually around 5700lb on most trips) travel trailer using a Blue Ox hitch. I also have real 5100's. (Truck details in signature).

Payload, GVW, GCW etc... are all below max.

My main objective for the Sumos is to stiffen up the rear end while towing. Currently the trailer tows well. I can easily return the front height of the truck with the Blue Ox. The rear end drop about 1.25 - 1.5 inches when all set up, but some sag is to be expected.

For the most part are trips are only 200 - 400 km within BC on single lane highways, with a max speed of 100km, but typically in the 90KM range. On these roads there is no drama.

We did a longer trip down to Oregon this year which involved some interstate travel. For anyone wanting to test how solid their set up is, the interstate is the place I got the push/pull from vehicles and semi trucks and certainly felt the really strong cross wind around Hood River.

Ok, now that you have the context, here are my questions for you:

1) If I place my foot on the hitch when it is all connected and give a good push to the side I am really surprised at how much sideways motion there is in the rear of the truck. I want to reduce this. Bottom line is feel the rear end its too soft. Do you think the Sumo springs will help?

2) My main concern with adding the Sumos is I may have to reduce the tension on the WD bars by one link. With the Blue Ox system the sway control is integrated into the sway bars. Less tension on the bars means less sway control. I have zero 'natural sway' but that doesn't mean outside forces wont induce sway. When you set up your WD hitch after the Sumo install did you have to reduce your WD bar tension?

Thanks in advance to those who respond.

Simnut

1) I've never checked the sideways motion of my truck when hitched. I will test that out (I'll try to do it this afternoon) and take a video of it. I have many guys come up to my truck when I talk about the Sumos , grab the box side and give it a vigorous shake. Many are surprised how hard it is to shake it. Stand by for that test.

2) I did have to reduce my WD bars by one link. Went from 4th link to 3rd link to make it all nice and level. But I did not notice any increase or inducement of sway of my rig. It is perfectly normal for a holiday rig to be pushed around by wind..the key is to have it move as a unit, not start to wiggle at the hitch. A lot of that can be "controlled" by proper loading of the trailer also. Do a Google search and look for the U-Haul trailer sway demo. It's a great demo on how sway can be induced or controlled by load. Actually, here is the link :


No little sway bars on that setup hehehe

Now, off to try out that sideways wiggle test!

mountaintruck

Thanks for the quick reply. Yes I have seen that video.

I think the entire rig is moving when being passed, but its hard to know for sure. My eyes are on the road in front, when being passed. I find the easiest way to hold my course when being passed is to look ahead to where I want to go, and as the push/pull is happening I gently counter with the wheel. I'm not really turning the wheel much at all, more resisting some increased force I feel on the wheel. It almost become second nature and I can anticipate it now.

I have had my wife watch in the mirror and the trailer is not swaying so much as moving a bit, which then wants to move the truck in the opposite direction.

acdii

Best way to tell if the setup is correct is to watch the left lane when a truck is approaching. As soon as the front gets past the rear of the trailer, you should feel everything move as one. If you feel the front move, then it isn't setup correctly.

If I'm thinking this out correctly, if not setup right, when the bow wave hits the rear, it will push the trailer rear away, moving the nose of the trailer in the opposite direction. So truck on the left, pushes trailer rear right, nose moves left, then trucks rear moves left and nose moves right. Then as the truck passes, the nose of the trailer moves right and trucks nose moves left.

Setup correctly the entire rig should be pushed right, then as the bow wave passes by and relieves the pressure it will be pulled left. Thats the Push/Pull being referred to.

As far as side to side play, while under load the Sumosprings pin the frame to the axle and should eliminate the side play greatly. Not so much when empty though since they are just resting on the axle at that point. I have the 1500 Pound ones, Simnut has the 1000 pound ones, so our results will be different, his truck will ride better under a light load, while mine will bounce, but with a heavy load of over 1000 pounds mine will be rock solid. I hit bumps and thats it, bump, no bump bounce, just bump.

Lets just say that even though they did not fix an issue I have, they did increase how well the truck rides with weight in the back and improved overall handling in turns and curves.