Andersen Ultimate center of weight vs rear axle

texasgiddyup wrote:
By the way, the highly rated B&W Companion 5th wheel hitch also places all weight and any movement directly on the truck bed steel, and not on any under lying support structure. It attaches to the truck gooseneck opening with its own shank in the hole, and is torqued pulling up on the gooseneck platform to seat the frame tightly to the truck bed. Same basic logic as the Andersen. The B&W is what I used on my 2011 chevy long bed dually and I never noticed any chucking or bed deformation.

The 18K did sit on the bed and it was designed when the beds actually were strong. My 18K DID deflect my 11 Dually bed. B&W replaced the base as it has bent a bit and supplied hard plastic strips to transfer load directly to the bed cross members that sit directly on the frame. The result is B&W re designed the Companion to be a 20K unit with adjustable strips that DO transfer the load to the bed cross rails then to the frame.

The Andersen Ultimate transfers the weight to the bed NOT the cross rails. They DO deflect the newer beds when towing in the upper weight ranges.

By the way, the highly rated B&W Companion 5th wheel hitch also places all weight and any movement directly on the truck bed steel, and not on any under lying support structure. It attaches to the truck gooseneck opening with its own shank in the hole, and is torqued pulling up on the gooseneck platform to seat the frame tightly to the truck bed. Same basic logic as the Andersen. The B&W is what I used on my 2011 chevy long bed dually and I never noticed any chucking or bed deformation.

I also called Andersen and got the exact opposite description than DAVISENVY. The Head of Sales said the weight is distributed over the entire andersen frame, and not directly on the truck gooseball. The attachment to the truck gooseball is with bolts going under the ball circumference and tightened to pull UP on the ball securing the Andersen frame tightly to the truck bed, serving the purpose of puck attachments that do the same job. No weight is placed directly ON the truck gooseball, in fact it is negative weight.

So the question remains where does this hitch platform place the center of that weight distribution in relation to the truck axle. To determine this I located the schematics for their steel and aluminum versions of the Ultimate hitch, attached below. Considering the aluminum one as my desired hitch, it shows a 31.5" platform length from front to rear. Half of that for the center would be 15.75", which would be 1.75" rear of the gooseneck ball center line looking at the aluminum version measurements.

Now the question is where is the truck's gooseball in relation to the rear axle. On my existing 2011 Chevy long bed dually, it appears to be about about 6" in front of the axle.

So the center weight would be 1.75" back of that, or about 4.25" in front of the axle - looking good!

To confirm a bit further, I looked up the installation instructions for B&W Companion hitch that was installed on this current Chevy, and it shows a 49.5" distance from rear of long bed to center line for gooseneck ball hole (44.75" for short bed). I measured 49.5" from rear of my bed and it aligns perfectly with the ball.

Now my next questions are 1) does the 2017 Chevy short bed factory gooseneck do a similar "set forward" for the ball over the axle; and 2) if the aluminum version distributes weight over the pads on the truck bed and not on a support structure, but the steel rail version does attach to pucks directly on a support structure, it would seem the steel rail version would be much firmer, right?

Steel Ultimate (not rail): Andersen Steel Ultimate measurements

Aluminum Ultimate: Andersen aluminum ultimate measurements

How does this hitch platform keep the weight distribution at least slightly in front of the rear axle for best handling?

Along with on topic opinions/ideas expressed here by some I would recommend giving Andersen a 1-800 for their input also.

Allworth wrote:
You gotta love it when everybody is smarter than the professional engineers who did the design!

The claim about the weight being carried would not have been made by an engineer of any sort, or even a mechanic. Just an employee making stuff up as he goes along. My own personal experience with their customer support produced similar less than impressive results.

This issue isn't an answer to the OP's handling question, just clarification of miss information that was possibly put out by an Andersen Rep.

A professional engineer that never took a physics 101 class?

You gotta love it when everybody is smarter than the professional engineers who did the design!

davisenvy wrote:
I called Andersen and asked them this same question. They said since their hitch hooked onto the gooseneck ball, that is where the weight is placed not 4in behind the ball as it appears. The "foot" of the Andersen hitch is just for added support, but does not support the weight of the FW, the GN ball does. Hope this answers your question.

That is insane. The GN ball on the truck is under tension and supports no weight. The hitch frame transfers the weight to the truck. And yes if the hitch and adapter moves to the rear then the center of pressure on the truck moves. This is basic physics.

davisenvy wrote:
I called Andersen and asked them this same question. They said since their hitch hooked onto the gooseneck ball, that is where the weight is placed not 4in behind the ball as it appears. The "foot" of the Andersen hitch is just for added support, but does not support the weight of the FW, the GN ball does. Hope this answers your question.

They need to hire a new mechanical engineer. You can NOT torque a hitch down to the bed floor with the GN and at the same time have the GN hold anything up. An't going to happen! The B&W, Andersen and similar hitches carry the weight on the bed floor, tophats and then the frame that the tophats rest on.

Mount a GoPro on the side of the bed to watch the hitch while towing and you will see the hitch ball moving back and forth as the bed flexes.

Andersen has not been very forth coming on this and for a number of years hedged on safety chains until finally offering them as an option. I ball hitch is a ball hitch, bumper pull, GN or Anderson. States that require safety chains(most do) would carry that over to Andersen when challenged.

Chris

davisenvy wrote:
I called Andersen and asked them this same question. They said since their hitch hooked onto the gooseneck ball, that is where the weight is placed not 4in behind the ball as it appears. The "foot" of the Andersen hitch is just for added support, but does not support the weight of the FW, the GN ball does. Hope this answers your question.

If an Andersen Employee actually said the weight is carried on the Gooseneck ball he is totally clueless. The ball in the bed of the truck not only doesn't carry any weight whatsoever, it is actually only used to pull on in order to anchor the base of the Andersen hitch to the bed of the truck. All of the weight is carried by the tripod structure and transferred to the bed of the truck. It he wanted to discuss angles of the tripod supports and the layout of the base of the frame it would be one thing, to state in any way the GN ball is carrying any weight just makes the person you talked to totally clueless.

For those who don't know how the gooseneck ball attaches, there is a square hollow tube with a smaller inner tube that slides over the GN ball, and has a whole drilled into the lower portion allowing a pin to be inserted under the head of the ball. The top of the inner tube is closed with a threaded top plate and the top of the outer tube has a hole for a bolt to protrude down through. A bolt goes through a hole in the top of the outer tube and is threaded into the top of the inner tube so that when tightened it pulls on the anchored inner tube. This action pulls the base assembly downward since the inner tube is anchored to the GN ball and can't move upward. There are also two smaller bolts in the front of the tube assembly that take up the slack between the inner and outer tubes once the hitch is anchored firmly to the bed of the truck. The GN ball is only used to pull the base of the hitch to the bed of the truck, and prevent lateral movement. All of the pin weight is carried by the base of the hitch resting on the truck bed. The position of the GN ball has no affect on the center of gravity other than by positioning the base of the hitch in the same location every time.