Placement of Fifth Wheel Hitch In Truck Bed Relative to Rear Truck Axle

Updated 10/13/2025 | Published 11/13/2011

Question:

where should the hitch be installed in respect to the axlein front of or behind the axle and by how many inches? thank you.

asked by: Dean D

Expert Reply:

The correct placement of the fifth wheel hitch will vary from vehicle to vehicle. It can also vary according to the type of install kit being used. Typically, the hitch will be installed so that the trailer king pin will be directly over or slightly forward of the center line of the rear truck axle. You never want the king pin rearward of the truck axle, because the pin weight of the trailer can actually make the front end of the truck too light. This can negatively affect braking and steering performance.

If you would care to respond with the year, make and model of your truck, as well as which hitch and install kit you were interested in, I would be happy to provide more specific install guidelines.

expert reply by: Mike L

Mark L.

3/19/2020

How about on a c4500 GMC 4 door can I put the fifthwheel hitch behind the axle and if so how fare behind the axle can i go

Chris R.

3/20/2020

There isn't a set max length that you could put the hitch behind the rear axle on your C4500. This is typically dictated by the particular base rail kit that you use (along with the attachment points on the truck's frame rails). Ideally you'll be a bit in front or right on top of it. I really don't recommend having the hitch behind the axle if you can help it. If you can tell me what model year your truck is, or what rail kit you plan on using, I will be happy to try and dig up some more details.

Mark L.

3/20/2020

Well I am trying to gain as much room as possible between the fifth wheel and the back of my cab like they do the semi RV haulers they put their fifth wheel hitch in the back of the frame not just slightly behind the axle

Chris R.

3/20/2020

I definitely understand trying to gain cab clearance for those sharper turns. The safest route I can recommend for this would be to either use a sliding 5th wheel hitch or replacing the pin box on the trailer with a pivoting model like the Reese Sidewinder, which actually shifts the pivot point 22" back from the hitch. I added links for our selection of both below.

Helpful Links

dept-pg-5th_Wheel_Pin_Box-pt-Provides_Turning_Clearance.aspx

dept-pg-Fifth_Wheel_Hitch-sf-Sliding_Fifth_Wheel.aspx

Jim B.

3/2/2024

@MarkL Thanks for the comment. I'm trying to figure out what I want to install in my vehicle and where to install at this point. Your site has been helpful. Thanks again.

Jim B.

3/2/2024

2019 Ford F-150 6.5 bed pickup

Mike L.

3/3/2024

@JimB Which bracket/rail kit are you planning on using? The Curt # C38ZV would place center of the king pin 2.006 inches forward of the axle centerline. Here's the install instructions: https://www.etrailer.com/instructions.aspx?pn=C38ZV The Reese # RP56034-53 places the kingpin center 1 inch forward of the rear axle centerline. https://www.etrailer.com/instructions.aspx?pn=RP56034-53

Gw J.

5/2/2024

2024 NISSAN FROINTIER 4X4 SV LONGBED (6FT) TOWING AN ESCAPE 5.0TA. I JUST PURCHASED AN A16/SLIDER HITCH WITH UNIVERSAL RAIL KIT. THE AXLE IS APPROX 32" (CENTERLINE) FROM CAB.

Mike L.

5/2/2024

@GwJ Typically, a mid-sized truck like the Frontier isn't designed to tow a 5th wheel trailer, Unfortunately we don't have any info on rail placement nor do any of the manufacturers we get our 5th wheel rail kits from. You could use a universal kit like # RP30035, and place the rails so that the 5th wheel king pin sits directly over or just forward of the rear truck axle centerline, but we don't offer any specific instructions or advice for that application.

6/20/2024

2017 GMC Sierra 2500HD, 6.5’ Bed, Using a B&W Companion “non-sliding” hitch.

Mike L.

6/23/2024

@Vb I'm going to assume your Companion will mount in a # BWGNRK1016 B&W Turnover ball gooseneck hitch. If that's the case, the king pin will be centered at a point 44-3/4 inches forward of the rear of the truck bed (not the rear of the tailgate). Hope that helps!

Chris

9/8/2025

@MikeL test

John H.

6/9/2025

My 2003 Dodge Ram 3500 4 Dr dually has a virgin bed having never been drilled. I’m looking at the B&W Patriot on rails. Looking for mount placement. Thank for your time.

Mike L.

6/19/2025

@JohnH The rear-most bed mounting rail will sit so that it's rear edge sits 23-3/8 inches forward of the rear edge of the bed for a long bed or 26-3/8 inches forward of the rear edge of the bed for a short bed. Be sure to measure from the rear bed edge, not the rear edge of the tailgate. With the rear rail in position, place the front rail in the bed, forward of the rear rail. Mount the hitch base in the rear rails, and use the the tabs at the front of the base to mark where the front rail goes. The linked product page has a link to the full install instructions for you to check out.... I hope that helps!

Mark R.

7/10/2025

Hello I recently purchased a B&W 25 K rated hitch from you folks. I am installing on a brand new F250 King Ranch with 5th wheel hitch package installed. It has an 8’ bed. I have started the installation and wanted to ask whether the Pivot arms should be 1” in front of axle or 3”. I also have installed the pivot arms at the highest setting on the base. The bed is 21/1/2 from floor to top rail. Thanks Mark

Mike L.

7/16/2025

@MarkR I'd install the pivot arms so that they're 1 inch forward of the rear axle. Let us know how you like the hitch once you get everything up and running!

Joe N.

8/23/2025

Installing a B&W 5th wheel hitch (Companion OEM for RAM Towing Prep Package- Dual Jaw-25,000 lbs. BWRVK3600) on a 2025 RAM 3500 Laramie Crew Cab 4x4, dual wheel drive, turbo diesel. VIN:3c6-3rrjl4sg-521888. Will be pulling a Grand Design 2019 Momentum 351M, Weight 13,600 pounds, 38' 9" in length. Please advise best position to arrange, adjust the pivot arms into the "Companion", for best results.

Mike L.

8/29/2025

@JoeN It will depend on your bed length, mainly. You'll want to set the height so that your 5th wheel tows as level as possible. You'll want the fore/aft adjustment set so you have the maximum distance between the front of the 5th wheel and the back of your cab. This is described in detail on page 5 of the owner's manual, which I'll link for you. Hope that helps!

Helpful Links

instructions.aspx?pn=bwrvk3600&alt=true