Reducing bounce with Reese dual cam.

[ncbrit]

I have a Sierra SLT, towing a 7600lb trailer with the Reese dual cam hitch. The truck and camper sit level, but I get what I feel is excessive bounce (porpoising). Is it a matter of adjusting the hitch to reduce bounce? The way the dealer set it up has me using the third chain link. If I move up to the next link, I assume that it will put more tension on the sprung bars. I can move one link without having to adjust the length of the cams. Is that the right thing to do?

[Ford Idaho]

Are you running LT or P=metric tires?

[ncbrit]

LT I believe. It's a brand new flagstaff. I'll check this evening.

[Ford Idaho]

Originally Posted by ncbrit

LT I believe. It's a brand new flagstaff. I'll check this evening.

Not the trailer, your Jimmy......

[ncbrit]

P275/55R20 Goodyear Wrangler's

[dsrace]

well what year is your gmc? 1500, 2500 3500? crew cab long box or standard short box? stock shocks or bags?

[asquared]

Are you sitting level or do you have rear squat on the tv. Is the tt level when hooked up. Tell us more about your TV. It sounds like you need better adjustment on your wdh.

[ncbrit]

It's a 14 Sierra slt with the all terrain package. It's a half ton. Crew cab with standard box. Shocks are the ones that come with the all terrain package.

TV and TT sit perfectly level when hooked up as the dealer showed me.

[Flagstaffer06]

Sorry to rehash, when the trailer is unhooked and the truck is sitting there, does your rear end sit higher than the front? If it does sit with the rear high when unhooked, does it sit the same way with the trailer hooked or does the truck squat and then actually appear level.

You want to try and get the same distance from the ground to the fender wells both hooked and unhooked. If it's showing lower when hooked, you might want to go up a link.

My truck sits rear end high when unhooked, when hooked I get about 1/4 of squat in the rear. I added a set of airbags and use about 20psi in them. It brings it to stock height, the trailer pulls right and it adds some support to the stock suspension stiffening it up a bit.

It sounds like you want to play with the hitch more and adjust it another link on the chain if needed. You want to go through the hitch manual again step by step. Alot of times, dealers setup the hitch and the consumer and the dealer think it's right but, it can be off still.

It still will probably take a little bit to get it dialed in but, you'll get there.

[ncbrit]

Ok gotcha. I'll have to hookup at the weekend and measure the height of the truck both ways. Thanks for the help.

[asquared]

When you say on 3rd link, is that 2 loose or 3 links under load? You do not want less than 4 links under load as the bars can bind. At 4 links under load, an adjustment in the tilt becomes required. We had the reese dual cam on our old tt, it is a pain to dial in but once correct it is a great hitch.

The absolute best way to check your setup is to go weigh it at a catscale. You will want to make 3 passes (usually $9-12 for first pass, $1-3 for each additional weigh in a 24 hr period). Do this with truck and trailer loaded, ready to camp with all passengers, pets, gear and a full tank of fuel. First weigh is just truck, no trailer. Front axle on scale pad 1, rear axle on scale pad 2. Second weigh is truck with tt no wdh. Truck as in first weigh, tt on scale pad 3. The difference in the truck Wright is your tongue weight. The difference in the total ticket weight is your trailer weight. Third weigh is truck with tt and wdh. Look at the truck weights, what happened to Your axle weights? The idea of a properly adjusted wdh is to bring the front axle as close to unloaded weight as possible without going heavier. You can adjust by wheel well measurements but I have found better results doing the weight method.


Also look at your scale weights to make sure you are within truck specs. The first weigh ticket will be used to do this. Subtract the total truck weight from the trucks gcwr to see your adjusted towing capacity. Subtract the total truck weight from the trucks gvwr to get your available payload. Your tongue weight has to be factored into your payload. Go back and look at your third weigh (with wdh). Is your truck under gvwr and are you under gcwr? Are you under max RAWR?



On edit- I see you are in hickory. There is a scale at the wilcohess in Conover (exit 133 of 40) and one at the country Mart in maiden (321 and startown rd)

[ncbrit]

Awesome. I get gas at that Wilco all the time. I'll take a look at the scale next time i'm in there.

[dsrace]

prob need to go with towing shocks like kyb mono max in the rear and i would do the front too. you prob don't have the 10 ply ( e range) tires either. both of those will reduce the bounce. then increase tension on load leveler.

[acadianbob]

We had a lot of bounce on a similar trailer/hitch setup. LT tires solved the problem.

[MickeyD]

Originally Posted by ncbrit

I have a Sierra SLT, towing a 7600lb trailer with the Reese dual cam hitch. The truck and camper sit level, but I get what I feel is excessive bounce (porpoising). Is it a matter of adjusting the hitch to reduce bounce? The way the dealer set it up has me using the third chain link. If I move up to the next link, I assume that it will put more tension on the sprung bars. I can move one link without having to adjust the length of the cams. Is that the right thing to do?

Load range E LT tires will help, but the shocks on the new GM trucks are fairly soft too(they really ride well though). Had the same problem with my equipment trailer and the shop truck, so I went to heavy duty coil over shocks and they helped a lot with bouncing, but the empty ride went to hell.

[Computer Nerd]

I had a Reese dual cam hitch. It's not the hitch but rather how much weight you are distributing. I had to play with it and found depending on how much weight I had in the front of the trailer determined how many chain links I left exposed on the distribution arms. Too many and I would get reciprocate bounce from the truck to the trailer.

[techntrek]

The WDH should be adjusted so you are on the 5th link, giving you the ability to go to the 4th link if your camper gets loaded up a big trip. I've done a lot of reading up on adjusting the Reese Dual Cam and the claim is it works best when adjusted like that. Plan on making the adjustment to mine in the spring.

[techntrek]

OldCoot, I got an email saying you replied on this thread, but I don't see it here... odd.

[prof_fate]

the all terrain suspension is different than the E85 (i think that's the code) for the towing suspenstion. I know the shocks differ, not sure what else.

Second, Reese says 4 or 5 links on the chain NEVER fewer. 3 is wrong. And the bar needs to be parallel the trailer frame when all hooked up and sitting level. You can tilt the ball mount to 'add links', but maybe you need a heavier bar.

We moved from an expedition to the silverado (4 door short bed 1500) and have no more porpoising...two things changed - the WB of the TV and how 'hard' I had to crank the bars to get things level - since the leverage changed as the WB got 24" longer.

So I"m thinking your bars/setup is wrong.

[OldCoot]

Originally Posted by techntrek

OldCoot, I got an email saying you replied on this thread, but I don't see it here... odd.

My comment was for a regular Reese Trunion WDH, really not pertinent to the dual cam. We always tilted the head until the bars were level when hooked up and had 3 links loose. We used dual friction sway bars.