I am "considering" trading my 2005 Dodge Ram 2500 4x4 Cummins for a new 2012 Ram 3500 4x4 Chassis Cab with a 143" wheelbase and 9' steel or aluminum flat bed. My questions have to do with pulling my 28 ft Dodge 5th Wheel camper with the 9 ft flat bed.
With the extra 1 ft (my current truck has a regular cab 8 ft bed) of bed length, would there be a clearance problem with the back of the flat bed hitting the 5th Wheel? I was thinking that I would tow the 5er with a gooseneck adapter instead of using a 5er hitch since all these flat beds seem to come equipped with a gooseneck hitch factory installed. Is there a problem with using a gooseneck adapter on a 5th Wheel? Would I have to instruct the bed builder to position the gooseneck ball a foot further toward the back of the bed in order to avoid clearance problems? I think most of the flat beds are 8 ft wide. Would I need to find one that is a bit narrower to avoid clearance problems with the 5er in turns?
The Chassis cabs come with the Aisin automatic transmission. With the standard wheels/tires (17 inch on the 3500 CC), what kind of rpms can I expect at 60 mph with the 4:10 gearing? How would that compare if I got a 4500 CC instead with it's 19. 5 inch wheels and 4:44 gearing?
Are you Andy Redmon of the Dallas area?
I am a huge fan of Ram's new cab and chassis platform and enthusiastically recommend them. I own an '08 3500 C&C with a CM flatbed.
SS Truck Beds
I tend to be conservative or cheap, depending on point of view, so I purchased the CM SS model flatbed rather than more expensive tow bed. I had the CM dealer add four large underbed boxes, two long ones in front of the wheels and two shorter ones behind the wheels. My bed is the standard 8' 6" length and it works great pulling my HitchHiker fifthwheel. I have plenty of clearance for swinging 90* or more from the trailer centerline.
CM's longer bed is 9' 4". I'm not sure it would allow sufficient clearance for a fifthwheel unless you move the gooseneck pocket rearward. You'll have to visit a bed dealer and take some measurements. Normally the gooseneck pocket is centered on the axle centerlne so an additional 6" (if bed is exactly 9') of bed might all be behind the axle and reducing clearance to trailer. CM beds have the back corners cut off at a diagonal allowing for trailer clearance so that might be okay. An experienced dealer could tell you.
I would also have a concern about moving the gooseneck pocket back very far. Moving the kingpin weight back behind the centerline of the rear axle will shift a good bit of weight rearward. The C&C has a 52 gallon fuel tank that is already at the rear of the frame. You might, (I emphasize might) shift enough weight back to cause enough lift on the front tires to create light steering and possible loss of steer or braking traction. Could you settle for a more common 8' 6" bed length?
I would recommend a phone call or visit to your bed dealer or manufacturer. The bed maker builds those beds on a form of assembly line with all parts cut and welded to a standard pattern. The gooseneck is recessed in a pocket under the bed deck and structurally reinforced. Moving the bed pocket to the rear would require custom work for the bed builder and would probably add significantly to the cost.
Like Rusty above, I also recommend
against towing a large and heavy fifthwheel on a gooseneck hitch. Lots of people do it but lots of people fracture the steel frame of their fifthwheel before they realize damage is being done. I called and discussed the issue with an engineer at NuWa, builder of HitchHiker fifthwheels, before I ordered my truck and bed. The engineer told me it was OK with NuWa, they felt their frame was strong enough (on my model, not all frames are the same) but the Demco hitch would probably not stand the additional stresses.
You probably already know, the deck of a C&C with flatbed is going to be several inches taller than your current pickup bed if it's 2wd. I don't remember the dimensions now but see the Ram Body Builder's section in the Ram truck website. You'll find all the details. If memory serves, the top of the frame rail height of an unloaded 3500 C&C was about 31 1/2" tall. Add the thickness of the bed of your choice and you'll know the deck height. It is TOO tall for a standard fifthwheel hitch. I had my CM bed dealer "surgically" shorten my old well-used Reese 20K fifthwheel hitch. I think they cut a 3 1/2" section out of the base to shorten it. It tows my fifthwheel level.
3500 cab and chassis platforms have much better springs than pickups and don't sag half as much as a pickup when you lower a heavy fifthwheel on it.
For a year and a half I've been driving my Ram truck very little and riding a motorcycle so my memory of engine rpm at road speed is fuzzy. I travel for fun now, am rarely in a hurry, so when pulling my own 14k lb. fifthwheel I've developed a comfort zone of setting the cruise at 62 mph and selecting tow haul mode on my Aisin which locks out 6th gear/2nd OD. Engine rpm is about 1800 - 1900 rpm if memory serves. (If you really need to know pm me and I'll get the truck out and drive it to refresh memory) I don't allow it to shift up into 6th unless I want to run 70 mph which is rare.
The choice between a 3500 and 4500 depends, in my opinion, of how you will use the truck most of the time. An empty 3500 C&C rides stiffer than a 3500 pickup but is not uncomfortable. An unloaded 4500 is, in my opinion, pretty stiff and would not be very comfortable as a daily driver on rough streets or for long highway trips. A heavy tow bed, fifthwheel hitch, auxilliary fuel tank, tools, chains, spare wheel and tire would help and might make it acceptable. I have not had the opportunity to ride in one fully set up. With a fifthwheel on the ball or hitch a 4500 would probably be nearly perfect. I wanted a 4500 and would consider one again if I were going to buy a new one. A 3500 C&C with Aisin/4. 10 gears is probably geared very close to a 4500 Aisin/4. 44.
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