5th wheel location?

[4x4e350]

I have a few questions about 5th wheels for you experts.
I have decided to try and keep the 5th wheel on my M818, but do to the fact I added a extended cab, I would move it back about 16", and remove the original ramps. My plan is to still build a flat bed around the 5th wheel, with a removable plate above and behind it.
MY question is, besides the obvious weight distribution, being placed completely over the rear axle, would you see any other issues? I don't plan on utilizing the entire 30,000# hauling capability, maybe 20,000# max.
Also, I removed the 1" spacers under the 5th wheel, which bolt to the angle iron on the side of the frame, I did this to lower the 5th wheel, and I couldn't use the angle iron along the sides anyway, because of the new location. I plan on drilling new holes on the top of the frame, then bolting the 5th wheel with backing plates. There is already holes drilled in the top of the frame for the ramps, and the 5th wheel line up with these pretty close. I'm just wondering if this could cause issues with the frame strength?
See the attached pic, it will explain the 5th wheel placement.

 

[mendo]

It's not really over the rear axle, even though it is over the rear axle. all the weight on the rear axle is supported in the center between the axles on the pivot. so by placing the 5th wheel where you have it in the picture, you put all the weight that you place on the 5th wheel behind the axles, the front wheels will be super light!! I would work on a solution to put it where it was, maybe only tow trailers that have very little hanging over the front of the pin.

 

[73m819]

the 818, being as short as it is, with the 5th wheel that far back, any large amount of weight will take the weight off the steer tires, just like the problems that the 543 and 816 have

MENDO types faster than I do, truth be told, EVERY BODY DOES

 

[4x4e350]

Thanks for the info.
I didn't think of that, the pivot point is between the axles, and it will remain there.

 

[Hammer]

You could put a civy slider 5th wheel, so you can have each different trailer as FAR forward as possible.
Still, with it that far back, I wouldn't haul much of anything that was either heavy, or would bounce much.
If you have a longer trailer, you can help it out by loading all the weight over the trailer tires.
Still a band aid approach though.

 

[Derrickl112]

Should have converted an 813 to a tractor....

 

[Derrickl112]

A gooseneck trailer would be perfect for it

 

[73m819]

A gooseneck trailer would be perfect for it

Not any different from a fifth wheel trailer still have the same weight transfer problem being behind the trunnion pivot point

 

[Derrickl112]

Not any different from a fifth wheel trailer still have the same weight transfer problem being behind the trunnion pivot point

I meant that he could move the 5th wheel back to where its supposed to be and wouldn't have any problems pulling a gooseneck.

 

[4x4e350]

I really like the short wheel base of the 818.
I will probably just stick with my original plan of only using the pintle hitch, I don't even have a 5th wheel trailer. But I thought it may be nice to have the option.
Actually, this will just make it easier (and cheaper) for me to make a bed now.

 

[73m819]

I meant that he could move the 5th wheel back to where its supposed to be and wouldn't have any problems pulling a gooseneck.

In that case, yes I see your point and I see it working

 

[Derrickl112]

In that case, yes I see your point and I see it working