Here's the text from the diagram, I can't post the image from the work computer.

ROW 4
29 5/16” Long Box,
6’ Box, & 5.5’ Box
Side Bracket
Axle Center
Front
of
Vehicle
Rear Edge of
Truck Bed
Drivers side of F150 shown
Measure from Rear Edge
of truck bed to rear edge
of base rail.
King Pin Center approx. 1 1/2”
forward of axle center.
Bed Sill

 

I've noticed when reading the installation instructions that the distance in front of the axle varies by brand of truck. In other words, it might be 2" forward on a Ford, and 4" forward on a Dodge (just random examples). This leads me to believe that the exact position is not critical, and that they have positioned the rails so that holes in the frame can be used wherever possible and spring perches are cleared, etc. When we say 2" to 4" forward of the axle centerline, it means just that. Put them anywhere in that range where the mount kit will work.

Very little weight is transferred to the front axle. If you weigh your axles with and without a fiver/gooseneck, you will see. Sometimes the front axle weight doesn't change more than 100-200 pounds. Moving that pin forward or back an inch makes very little difference in weight transfer.

 

Hi folks...
I have been using the B&W Gooseneck plus 5th wheel option for 3years. I installed the system on a 2008 Dodge 3500 over 3 yrs ago. Easy install & very well built under the bed system. When I am not towing, there is nothing in the way, a clear flat bed. August 2011 I traded the Dodge in on a 2011 F-350. I have installed another B&W under bed hitch system. Great hitch! The instructions are clear and informative. Once installed, it still has thr ability to be fine tuned. The height above the bed, and the fore & aft position. Mine is adjusted to place the King Pin a couple of inches forward of the rear axle center line. The truck tows my 33ft 5th wheel Wildcat just great!! (12500 lbs)

 

Approximately 1 1/2" to 2" inches forwards of the center of rear axle, as mentioned about acceleration and weight being forwards with steering as a concern but also when breaking and the forward motion exhilarated at times will push down on the bed due to the trailer pushing some, if it pushed down behind the axle there would be a lifting motion to the front of the towing vehicle,,, with the down ward force forward of the rear axle, there is pressure slightly more toward the front axle with out a great amount of exertion causing any front axle or steering damage,, however just enough that it will help to cause a better steering effect,,, this is why only a short amount of distance is forward of the axle.
Not knowing certain measurements, I would not assume any thing about the wheel wells and be sure to mount those angles down to the frame as well and the upper rails through the bed to the angle, no matter if it is a light load or heavy, if it is all treated the same, the fact of explaining why it wasn't latter could be left to family members after some ones funeral .
I tend to get a bit serious about towing, my apologies, I love towing though. I wish to keep towing and for my family to feel safe and by informing just one person on the East coast about a simple little detail helps them from causing a death due to the old way of thinking of " IT WONT HAPPEN TO ME" well first of all, its not about him,,its about those he will be driving around and it is about them and their safety,,,,,, The life saved could be the one person whom will be my son in-law or daughter in-law some day or the person that could have saved my wifes life by simply have read a special article in a magazine and was standing next to her when she collapsed ,,,,,, Life is special ,, why play with it by saying It wont happen to me , My son, daughter, wife as well as my self will be forever grateful for taking the time and installing your hitches while thinking of us. I think of YOU !

 

+1 That would be my thought as well.

 

I have a related question. If I'm towing a 24', ~5500# 5th wheel (4100 dry as per Fleetwood), does it really matter if the hitch is 2" in front of the axle, or on top of it, or 6" behind even?

My reasoning is this, I would tow that size and weight in a tag along configuration with the proper WD hitch setup. By having this size trailer, just having the tongue weight 30" farther forward should be a huge benefit, even without the leverage of the WD bars.

I only ask because I don't really want to spend the $900 on a Sidewinder, but some crew cab trucks have the axle in the front 1/3 of the bed.

 

Having too far to the rear may make it a little sqeamish but yes you can do it.

Don't want your front end to get too lite.

 

I'm looking at the PullRight "Better than industry standard" rails that use existing frame holes, but I'm not sure if I'll be able to remove the rails for a "clean" bed like I want.

Just wondering if anyone else has the same thought on mounting the rails using existing holes vs putting "new" holes in it.

 

Another reason you DON'T want the pin behind the rear wheel is because that trailer pushes you in a turn more than you know, and if the pin is behind your rear axle, one day on a rainslick road, your trailer is gonna do a PIT manuever on you......

 

From the installs I've done, the placement really depended on the vehicle and where the rivets are in the truck frame. The brackets that attach to the frame need to sit flat and the rivets can get in the way so the bed mounted part moves to accommodate.

If the hitch is vehicle specific it's already taken into consideration where the frame brackets are going to attach.

 

If you want a clean bed you should look at the B&W Turnover Ball and Companion hitch setup.

 

I don't disagree with this as I've seen it happen. But shouldn't any fifth wheel mount, even if farther behind the axle than recommended, be better in this situation than a conventional ball mount?