I am trying to determine where to put the ball in the bed of my Dodge in relation to the rear axle. Information I researched shows anywhere from 6 to 2 inches in front of the center of the rear differential. I looked at two SRW Dodge Quad Cab 3500 long bed CTD powered trucks with 5th wheels in the bed while parked in parking lots without their trailer connected when I was holidaying in Phoenix and Tucson. The 5th wheel appature center was directly in line with the center stake pockets and center of the rear rims indicating it was over the axle center. The owner was not around and I could not talk with them, but I noticed the 5th was not a slider type.

When I had a 1969 and a 1976 Ford 3/4 ton pickup with a long bed the fifth wheel pin appature center was position directly over the rear axle. I had as much as 12 ton of hay on the tri-axle 24 ft flat deck trailer and never experience any instability problems.

Where do you Dodge owners with fivers or goosenecks position your tongue weight to bear in the bed? Thanks for the advise and information.

 

I installed a drop ball and cut the hole exactly where the manufacturer told me to. I should have took another look. My truck is 2wd dually and the ball is almost 6" ahead of rear axle centerline. I pull 15,000# and when I weight the truck the front axle weight is just a few hundred pounds from being overweight while rear has plenty more capacity. My 96 model club cab dually with V10 had the ball about 2" over center and it done great. I plan to move my hitch back about 2.25' inches to keep from having to completely murder my bed. The safety chain brackets will get basically shifted one hole leaving one old hole and the ball hole will be enlongated probably try to patch this and get Linex to repair liner. This stinks I should have double checked before drilling hole. I think you could run the ball further forward like 4-6' on 4wd truck with no problem but 2wd defenately should be 2-4" over center.

 

My 5er king pin is 1.5" to the rear of the rear axle....tow,s just fine.
The only reason I put it there is because of other holes drilled in the frame from airbag brackets that used to be on the truck. If I recall, the directions that came with the hitch (Reese) said from 1" behind to 2" forward....probably not what it said, but that's what comes to mind.
Anyway, I never really understood what difference a couple inches fore/aft of the rear axle center would make. What if you were towing a 10k bumper pull with 1,500k on the hitch ball? How would that be worse than a 14k goose/5er with a 2,500k pin weight 2 inches behind the axle?
I don't know.....for me it's one of those things I can't let myself think about too much. My truck works the way I set it up, and that's fine w/me

 

With a 1,500 pounds tongue weight on an under bumper hitch the SRW tires are not overloaded, nor is the leverage component over the rear axle fulcrum raising the front tires enough to cause a significant problem during certain road surface conditions that reduce traction under the steering axle. I think a class IV under bumper hitch is rated to safely handle 1200 to 1800 pounds tongue weight on my Dodge. A gooseneck tongue weight of 2,500 pounds slightly behind the rear axle would not cause problems either for the SRW tires or present leverage problems for steering. I do know my truck's curb weight, but I do not know the front curb weight or the rear curb weight. The two SRW load range E tires can safely handle 3,195 pounds of weight when the tire air pressure is 80 psi. That maximum tire load minus the rear curb weight is the maximum allowable tongue weight if the ball is directly over the rear axle. As the ball is placed behind the axle a certain amount of front curb weight is lifted off the front tires and transfered to the rear tires due to the leverage effect over the rear axle fulcum. The ball location is critical for achieving maximum tongue weights, when part of the tongue weight can be transfered to the front axle. My flat deck fifth wheel had a sliding tri-axle carriage to enable me to place more trailer load weight on the trailer tires and relieve some of the tongue weight off the truck by moving the trailer axles forward. That feature was great when pulling heavy loads with a SRW pickup. Unfortunately, not all trailers have moveable axles and heavy trailer loads place excessive tongue weight on the truck's rear tires. On a farm excesive overload weights can be encounter now and then. On farm fields the excessive weight is not a problem because speeds are slow, but at highway speeds with excessive weight on tires a tire failure is possible. Also the DOT does not look kindly on axles being overloaded.

A ball position directly over the rear axle would cause no leverage problems whatsoever to the steering axle, but the rear tires could be overloaded if no portion of the load weight was shared by the front tires. On the other hand, the heavy diesel engine, front differential and Quad Cab are so heavy on the front tires that too much weight transfer forward is not desireable either.

 

Leon441 what type of hitch do you have? I bought the B&W Turnover Ball and it's way too far forward on my Dually. I believe it's made for SRW trucks pulling campers.

 

in installed my hitch in the new drw. of course followin g the manufacturers directions my pin sits about 1 inch to front of center of the rear axle

if you wind up in back of the axle you will lose some of the weight transfer to the front axle. an inch or two one way or the other won't hurt but too far in back of the axle will eventual cause an unstable ride.

unless you are trying to fab your own hitch the manufacturers brackets will put your hitch in the proper position for your truck

typically the turn over ***** sit further forward than a fiver king pin set up

i had both in my for 3/4 ton the turn over sat in front of the fiver rails

 

The reason the gooseneck's weight bearing ball is more forward as compared with a 5th wheel's locking king pin location in relation to the rear axle center line is due to it being expedient rather than practical. A heavy duty 5th wheel is bolted down to two supporting cross members sitting up against the underside of the box floor while the members are in turn supported on the frame rails by spacers that are all secured to the frame rails. The two 5th wheel cross members can straddle the tail pipe bend, that passes over the axle, to position the 5th wheel and thus the trailer king pin nearer to the axle center line. On the other hand, the gooseneck hitch cross member sits lower down away further under the box floor underside. It is rather bulkier and supports the ball sitting on top of it through a hole in the box floor. If the gn cross member is positioned near to the center line of the axle it can interfer with the 4" tail pipe bend, especially if the gn hitch is a ball turn over type. Thus, the bulky gn cross member has to be further forward away from the axle to clear the tail pipe, and consequently the ball must be supported on that cross member. The trailer's tongue weight should bear nearer the axle to prevent overloading the front axle. The tail pipe may need modification to accomodate a gn cross member in the correct location.