5th wheel hitch location

[s.kelly]

]Decided to go directly above axle, and will advise as soon as I pull the 5er. I am not too worried about added weight over the axle because of the air bags and sway bar I'm installing. Plus, I run motorhome tires on the rear.

Appreciate all the input. This is a great forum.



S. Kelly

-- email address removed --

 

[Schlickenmeyer]

No expert, but the research I did before getting mine said directly over the axle. The shop I had install it has a great reputation, and this is where they put it, without my input. To prove they nailed it, the weight on the front axle changes by only 20lbs when weighing with/without the trailer attached. (aprox 3000lb pin weight). and that may have been the kitty litter I had when I stopped by without the trailer!



My proof is in the fact it tows great, I have had several panic stops due to &$^*@$@# people, and once hydroplaned across an entire lane in a very heavy storm, and the trailer stays planted firmly behind the truck. No 'porpising', bucking, etc. .



Just my $. 02 worth

 

[BimmerAgent]

The shop that installed mine put it right over the axle. Tows great. Bruce

 

[Grizzly]

Welcome to TDR. It's a great site for information from a lot of friendly people and a few not so friendly. Do include your signature as it helps when answering questions. What is the pin weight of the 5th wheel?

 

[RustyJC]

Follow the instructions supplied with your hitch of choice. Since you have the long bed, you have the luxury of choice in pin placement. Most hitches will position the kingpin bore from 2" to 6" ahead of the rear axle.



Rusty

 

[klenger]

Just make sure it's at least 4' from the back of the cab. 4' 2" would be even better.



What kind of hitch is it? Some installation kits can only be mounted in 1 location.

 

[RustyJC]

Just make sure it's at least 4' from the back of the cab. 4' 2" would be even better.

Or, if you have a 102" wide RV (ours is 101. 5" ), at least 4'3" with 4'5" preferred.



Rusty

 

[SHobbs]

I have mine about 1" back from top dead center of the axle with no problems. Seems that under my bed there are some channels running across the width of the bed that prevented it from being right in center. Could have moved it forward but I figured that 1" would not be a problem. I kinda like it where is it I can tow the 5er and leave the tailgate down with no problems hitting it.



Rusty,

Those mobile suites are nice units, heavy but very posh. Looked into them before getting my current 5er and they were just a little more than what I wanted to spend.

 

[RustyJC]

Rusty,

Those mobile suites are nice units, heavy but very posh. Looked into them before getting my current 5er and they were just a little more than what I wanted to spend.

They were more than I wanted to spend, too but my wife said, "This is a gottahaveit!!!" :{ :{



Rusty

 

[SHobbs]

Rusty,



I see, the boss had the last word huh. :-laf

 

[RustyJC]

After 36 years of marriage, I don't begrudge her the RV she wanted. :-laf



Rusty

 

[SHobbs]

Rusty,



Hey congrats on the 36 years, not too many make it that far these days. I know I am one of them, been down that marriage road twice.

 

[LEPage]

Opitmum placement is at least 1" ahead of the C/L of the rear axle. The whole idea is that the weight not all sit on the rear axle, but balance out the load on the truck. Why over load the rear axle, with room to spare on the front? The futher back you go the more weight it is going to actually remove from the front axle. And keep in mind, the front brakes on the tow rig are the ones doing most of the work when you've got to stop hard. This is more important than being able to turn your truck 90* to the trailer. After all, look at how tight can you turn a TT, & it's been working for many years. If you have a 4X4, the top of bed to trailer is going to be an issue many more times than the trailer clearing the cab. Also, if the pin box is at least even with the front of the trailer, it will allow tighter turns than one that comes straight down out of the trailer. Most fivers under 18k have extended pin boxes to some extent. Even my 21K Supreme has a somewhat extended pin box. No "pro" here, just years & miles of experiance pulling heavy fivers.

 

[dcoffman]

Mine is about 2" in front of axle. The fifth wheel part. It adds about 100lbs on the front axle . It really pulls great. My brand F had it right over the axle and did not tow as good -same trailer.

 

[klenger]

Just a note about distributing the weight to the front axle by locating the hitch forward: The percentage of weight put on the front axle is directly proportional to the ratio of the distance from the rear axle to the pin / wheelbase. Lets assume at 160" wheelbase and 2000# pin weight. Moving the pin forward 1" will move (1/160) * 2000 lbs = 12. 5 lbs of weight to the front axle. To move 100 lbs forward would require the pin to located 8" forward of the rear axle. The impact of the changing fuel load would have far more impact on weight distribution than hitch location.



Disclaimer: These calculations are based on static loads only, and do not take into account dynamic loads caused by the weight being forced against the truck from braking, etc. That's way beyond my knowledge.

 

[REndres]

I think there is plenty of weight on the front axle without adding trailer weight if not needed.