Is the Eagle Cap 1165 Too Big and Heavy for a One-Ton Dually?

Is the Eagle Cap 1165 truck camper too big and heavy for a one-ton dually? After surveying several Eagle Cap 1165 owners at last month’s Truck Camper Adventure Quartzsite Rally, the answer might surprise you. What prompted the survey, of course, is the recent incident involving Michael Pavel’s 2020 Ram 3500 dually in Baja, Mexico. Not only did he overload his truck, but he had also placed an inordinate amount of weight behind the rear axle. After two years and 25,000 miles of use, this dangerous combination eventually led to a catastrophic split in the one-ton truck’s frame. In previous articles, we focused on Pavel’s Ram 3500 DRW truck and how the entire incident could have been avoided by simply doing a little research on the payload rating of his truck. In this article, we turn our attention to the weight and design of the Eagle Cap 1165, a four-season, triple-slide truck camper built by Adventurer Manufacturing.

First, it’s important to say that the Eagle Cap 1165 is a fine camper, a veritable hotel-on-wheels with a smorgasbord of amenities that would make any truck camper owner drool. These amenities include three-slide outs, a dry bath, gargantuan holding tanks, a comfortable sofa, 2-inch thick, laminated aluminum-framed walls and flooring, a side step, R13 insulation, and a massive heated storage bay in the basement. While all of these features makes for a spacious, four-season truck camper, it all comes at a cost, making the Eagle Cap 1165 a VERY heavy truck camper. According to the Adventurer Manufacturing website, the official dry weight of the Eagle Cap 1165 is 4,917 pounds, which is nearly 1,000 pounds heavier than the best-selling Host Mammoth 11.6, Eagle Cap’s closest competitor.

Robert Hallock is one Eagle Cap 1165 owner with whom we spoke. He bought a used 2015 Eagle Cap 1165 and mounted it on his 2018 Chevy Silverado 3500HD rated with a 6,219-pound payload. With a reported dry weight of 4,917 pounds, he thought he would be okay hauling an Eagle Cap 1165 on his one-ton dually, that is until he put the camper on his truck.

“I couldn’t believe how much the truck sagged,” Hallock said. “The camper had no bed mattress and no propane tanks when we bought it. The grey, black, and fresh water tanks were all empty, so I took it to the CAT scale to get it weighed. According to my calculations, the camper dry weight was 5,675 pounds. Granted, we were still under the weight limit of the truck, but that was before we added fresh water at 8.34 pounds per gallon in a 66 gallon tank, which adds 548 pounds to the weight of the truck camper and filled two 30-pound propane tanks that weigh 55 pounds each when full, which adds another 110 pounds, bringing the total of the truck camper’s weight to 6,335 pounds. Now, add clothes, food, and tools to that number and we were way overweight. The last time I had the camper weighed it was 7,223 pounds fully loaded. ”

The dry weight of a camper is supposed to reflect how much a camper weighs after it’s constructed. The dry weight does not include things like batteries, water, and propane. Instead, these are reflected in the camper’s wet weight calculation, which also includes options. This is where the manufacturer’s liability ends. Anything you add afterwards is on you—the consumer. Incidentals like clothing, tools, gear, and food will add anywhere between 500 and 800 pounds for a camper of this size. Aftermarket modifications add even more weight. Of course, passengers and anything loaded into the cab of the truck will add even more weight. It goes without saying that staying at or below the GVWR/payload rating of your truck is important for safety and liability reasons.

Unfortunately, the Adventurer Manufacturing’s Eagle Cap website no longer offers a “build a camper” feature. This excellent feature used to allow those ordering a camper to choose options that provided a more accurate weight of the camper as built. To the company’s credit, however, Adventurer Manufacturing still affixes a GVW sticker inside all of its campers that provides both a dry weight as well as an “actual weight” with all options (see sticker below).

So is the Eagle Cap 1165’s factory dry weight of 4,917 pounds accurate? Probably, but who orders a bare-bones 1165 with zero options? Customers buy the Eagle Cap 1165 because of its luxurious accommodations not because they want to rough it. This usually means adding amenities like an air conditioner, which is a must-have for anyone who likes to camp in the summer. But if you like to camp off-grid—and most of us do—this means you’ll also need to order the optional Onan 2500i generator or opt for a large bank of lithium batteries and a 3,000 watt inverter to run that air conditioner. Then, of course, there are the awnings. Many owners opt for those too. All of these options add even more weight to that 4,917-pound figure, meaning you could be staring at an official Eagle Cap 1165 wet weight of 5,400 pounds or more. We confirmed this number with several Eagle Cap 1165 owners who attended the last month’s Truck Camper Adventure Quartzsite Rally.

Which segues nicely into another bone of contention we have with some builders. Weighing each truck camper at the factory should be mandatory because it let’s prospective owners know how much each camper actually weighs. It should NOT be based on engineering estimates, but on a certified scale like those used by Ford, GM, and Ram. Some truck camper manufacturers do this, yet some don’t. Our query to Adventure Manufacturing went unanswered, so we don’t know if the company weighs each Eagle Cap camper or not, but this is something that every truck camper manufacturer should be doing. It goes without saying that providing the consumer with accurate factory weights is vital. Without an accurate weight, buying the right truck is difficult.

So how heavy is the Eagle Cap 1165 in real life? Fully loaded, all of the owners we surveyed at last month’s rally stated that the Eagle Cap 1165 weighs anywhere between 6,820 and 7,860 pounds. Again these numbers include everything, including passengers, food, clothing, gear, bicycles, aftermarket mods, and trailers. If you like to tow—and most of us do—you have to factor in the tongue weight of your trailer too. When building a rig, a visit to a local CAT scale is vital. We recommend visiting the scale first with just your truck. This let’s you know how much weight you can actually carry without going over the GVWR and payload rating of your truck.

Then there’s the issue with the Eagle Cap 1165’s center of gravity (COG) of 61.5 inches. A majority of super duty/heavy duty trucks on today’s road have a 60-inch cab-to-axle (CA) distance. For these, this places the Eagle Cap 1165’s COG behind the rear axle. Ideally, you want to see the center of gravity in front of the rear axle not behind it. However, the center of gravity in all of the Eagle Cap 1165s that we surveyed were well beyond the 61.5-inch mark and were instead a good 6 to 8 inches behind the rear axle. This places undue stress on the truck’s frame that can result in a catastrophic failure like the one experienced by Michael Pavel. The solution, of course, is to buy an appropriately rated truck with an 84-inch CA distance rather than one with a 60-inch CA distance.

Compounding the COG issue, is the Eagle Cap 1165’s massive rear storage bay. This heated compartment is practically begging to be loaded with gear, but care must be taken when loading it. Most end up storing heavier items in the rear simply due to the fact that this makes getting to the gear easier. One 1165 owner mitigated this issue by pushing the storage bulkhead forward about a foot and by pushing the rolling drawer assembly forward about 18 inches to make better use of the storage space and to move the weight further forward.

Mark Cymbaluk, owner and CEO of Overland Explorer Vehicles (OEV), is an expert on COG and loading, having built one hundred rigs over the years. He has read quite a few articles and posts on social media lately all showing the same thing—compromised truck frames from loading the chassis incorrectly.

“In all reality, you can be a bit heavy on most chassis and get away with it—for a while,” he said. “You should always adhere to GVWR and GAWR weights, but what will catch you in more ways than one is loading the chassis aft of the rear axle. There is not a truck manufactured today—commercially or privately—that is designed with a chassis that is meant to be in tension. When you load a chassis heavy behind the rear wheels, (and a degree of this applies to load COG directly above the axle centerline as far as vibration and harmonics are concerned), you unload the front axle. In this case the load point designed in the center of the chassis goes into a tension moment, you basically have a heavy weight using the rear axle as a fulcrum to lift the front axle, along with it a heavy engine.”

“When this happens you take the frame from an level unladen stance, and “bow” the center up. Now you drive down the road, you have a higher COG due to the load, this amplifies the moment on the chassis under tension, it basically flexes up and down much further than a properly loaded chassis as it starts out with upward deflection the moment the camper is put on. This moment is enhanced by the natural direction of travel, braking, accelerating, terrain, torque reaction, etc. Now add rough roads, vibration, harmonics, maybe a bolt hole with a sharp edge, the heat affected zone near a crossmember (inherent stress point), etc. and the beginning of the end has started, the chassis is experiencing far more motion than it was designed for, continuously. This is a 100 percent duty cycle, in the wrong direction of intended loading. It almost wouldn’t have mattered what the payload was on Pavel’s Ram, it was the way that the load was carried that killed it…. A 4500 would have been a better choice, but a 84-inch cab to axle chassis would be the ultimate solution,” Cymbaluk said.

After surveying the dozen Eagle Cap 1165 rigs present at last month’s rally, it’s apparent that most of the owners had done their homework when it comes to buying the right truck. Most had their camper mounted either on a class 4 (Ford F450, Ram/Chevy 4500) or on a class 5 (Ford F550, Ram/Chevy 5500) truck. The payload ratings of these trucks are approximately 7,850 pounds and 10,700 pounds, respectively. Unfortunately, one particular owner, who had his 1165 mounted on a regular cab Ram 3500 dually with 2WD, and a Cummins 6.7L diesel, told us he was overweight. He thought he would be okay having a GVWR of 14,000 pounds and a payload rating of 6,217 pounds. Fully loaded, his setup weighs 6,820, putting him 600 pounds over his payload rating. Making matters worse, the COG for the camper is a good 8 inches behind the rear axle. Plans to sell his truck and camper are already in the works.

But as one Ford F450 owner discovered, a class 4 truck is no panacea when it comes to hauling a heavy camper. Immediately after the rally, this particular owner took his rig, consisting of a 2013 Ford F450 and a 2015 Eagle Cap 1165, to a local CAT Scale to get weighed. He was horrified to learn that his truck was overweight by whopping 2,400 pounds. With a GVWR of only 14,000 pounds and a payload rating of only 5,443 pounds, his truck was woefully overmatched by the 1165. The CAT Scale printout showed 5,160 pounds on the steer axle and 11,280 pounds on the drive axle for a total of 16,440 pounds. Before buying the truck, he was told his F450 could carry “anything” that he wanted and “not to worry.” Obviously, this wasn’t the case with the 1165. When it comes to payload, this illustrates how far today’s trucks have come from trucks that are 10 to 20 year older. Always research before you buy.

Which leads us to probably the most important question of all: Is the Eagle Cap 1165 too big and heavy for today’s one-ton dually? For the most part, the answer is yes. It’s true that the 2023 Ford F350 dually offers a maximum payload of 8,000 pounds, yet in order to hit that lofty number you need to order a regular cab truck with 2WD, a gasoline engine, and an 8-foot bed. Ditto for Ram, which offers a 7,680-pound maximum payload, and GMC/Chevy, which offers a 7,442-pound maximum payload for the same configuration. However, most truck camper owners opt for a truck with a 4WD, a crew cab, and a diesel. Depending on other options, this configuration nets a payload anywhere between 5,000 and 6,000 pounds. In Michael Pavel’s case, his payload was only 5,178 pounds. Obviously, this rating wasn’t and isn’t high enough to haul what is probably the heaviest slide-in camper being built today. If he had consulted with us beforehand, we would’ve advised him to go with a class 4 or class 5 truck with a custom truck bed.

Robert Hallock, of course, was overweight by 1,000 pounds after mounting his Eagle Cap 1165—to say nothing about the camper’s COG—before upgrading from a Chevy Silverado 3500HD DRW to a Chevy Silverado 5500. This move probably saved him from a fate similar as Pavel’s.

“We were way overweight. This forced us to upgrade our truck to a Chevy 5500 with a much higher payload. This added expense was not in our budget when we purchased our truck camper. I’m not sure if the wrong sticker was on the camper or not, but I would really think hard before putting a camper of this size on anything less than a 5500 or a F550 truck,” Hallock said.

Not surprising, Adventurer Manufacturing made the decision in 2022 to halt construction on the Eagle Cap brand of truck campers indefinitely. The company instead will focus on putting out the smaller and wildly successful Scout and Adventurer brand of truck campers.