5th wheels and stability

[DickWells]

Having just read the thread in here about a 6.5 and GCWR, I've had a re-occurence of a question in my feeble old mind!
I've never towed a 5th wheel, but have towed a goose neck quite a bit. It always has seemed to me that the location of the pin in a 5th wheel, being up there above the wheel wells would put the center of gravity of all that tongue weight at a less stable attitude than with a goose neck. Am I wrong or right? What are the factors that I haven't mentioned that will come into play?
I determined a long time ago that I would never haul a goose neck or 5th wheel with a SRW pickup. Just my opinion, just my opionion! This is based on my son's 96 Cummins 2500 HD W/SRW. He's a whole heck of a lot happier now, with his DM Doolie.
I mentioned in here a while ago that I saw an F150 lose it while passing me with a very light little 5th wheel. I've never seen a pickup buck and sway like that thing did! He fought it down and slowed down and I went on by his white face, and never saw him again. That same year, I met a man in a rest area in GA who had a flat on an outside dual on his F350 W/5th wheel. He told me that if he hadnn't had those duals, he never would have been able to hold it, to get it stopped.
Just wondering what the guys in here hauling 5th wheels have to say. I've never wanted one. Don't like front bed rooms in any trailer, and I really like having my Whole pickup bed to use. Just me.
Dick Wells:)

[SmithvilleD]

Stability of the trailer & load itself relates to the trailer/load's center of gravity.

I think the towing stability benefits of goosenecks & 5 wheels come from a couple factors: Longer "tongue" length (tailer wheels to hitch point) & relative leverage on the truck.

In comparable bumper hitch trailers, the one with longer tongue usually tows better regarding tendency to sway or push the truck sideways.

Bumper hitch trailer's have the distance btwn rear truck axle center & hitch point - as a lever arm for (wind, etc.) sideloads to act on the truck. Goose-neck & 5 wheel hitch points are typically much closer to the truck's rear axle center. So the sideloads act with less leverage.

Certainly there are tradeoffs in ease of setup, price, ability to still use the truck's bed, etc. In trailers of similar load capacity, I've found goose-necks to be far more pleasant to pull. And also more maneuverable.

[MacDR50]

I like the goose neck set-up but my trailer warranty does not. According to the frame manufacturer (Lippert) they do not recommend the goose neck as it puts too much twisting stress on the frame. I guess the 5th wheel effectively reduces the length of the lever on the trailer to truck connection while the goose neck increases it. In both cases the trailer is at the same height over the truck bed/axles and this may be the most important factor but I am not sure.

As far as SRW vs DRW I agree the DRW has the better stability but a well balanced 5th trailer with a SRW truck that runs level under the PIN load and a proportional brake controller with a boost option so that the trailer drags on the truck during braking is a safe combination. The extra wheel of the DRW is obviously safer. Where I work we have some heavy (12-14K) conventional hitch trailers that we will only tow with a DRW 450/4500. Those beasts can push the rear end of a SRW truck sideways too easily. BTW our DRW trucks have a convertable GN and 5th hitch system.

[SmithvilleD]

Yeah, I meant lateral forces that cause trailer sway - regarding the leverage/tongue length statement. The 5 wheel's max ratings seem to go higher & they look to me like most designs probably have more safety margin in the design. Takes a good deal of steel & proper triangulation to make that last vertical on the gooseneck strong enough & it's got to be longer to reach bed/ball height - vs 5 wheel height.

Definitely agree regarding bumper hitch -vs - either goose or 5th wheel. The gooseneck's are easier (meaning more control for a given truck) to pull when the loading is less than ideal also.

I bought my project truck w/ a headgasket out & it was about 4 hrs away. Borrowed an HD 3/4T 5.7 gasser with typical conventional hitch. Rented a trailer rated to carry 8K and rolled out to central KS to get my newly purchased truck.

Got there & figured out the rental trailer's fenders where slightly narrower than my truck's front wheel's track. (Trailer probably better suited for hauling skid loaders, etc.) Anywho, debated climbing the project truck's front tires over the fenders & potentially bending them up, or backing the project truck on the trailer backwards since the rear track is just enough narrower to squeeze by.


I knew truck on the trailer backwards put the load's center of gravity behind the trailer axle's centerline - not good. Also the rental trailer had the common rental trailer hydraulic actuator brakes which aren't helpful if 'ya'd like to try dampen sway with some independent trailer braking. Being 4 hours out into KS made an additional 8 hr roundtrip with better suited trailer an unattractive option.


Took the trip home slow on backroads to keep sway/control issues under control. So got the job done; but a gooseneck trailer would have made that trip safer, less stressful, & a bit faster with the same tow vehicle - even if 'ya still had to load the project truck on backwards.

[DickWells]

Thanks fellas. About what I was thinking. A goose neck does have to be plenty stiff to hold rigid down to the ball, for sure.
I haven't towed a tag-along that was too much for the horse, since way back when I was still in my teens on the farm. Back then, it was almost routine. My Dad was always towing something too big and heavy on a tag-along trailer, such as a 4000 lb Ford tracter on a Model A single axled trailer behind a 51 Chevy half ton! Picked the front wheels of the Chevy off the road going down hill. Another lively ride!
The hitch set up is key to trailering joy with a tag-along. Until last year, I used a dual cam hitch and liked it very much. Certainly a whole bunch more stable than that F150 that I mentioned earlier! I changed to a Hensley Hitch last Summer. It works as advertised, but only after you've got it set up correctly. Being a full timer, I see (usually passing), all kinds of settups that I wouldn't be caught dead with. I try to take a glance at the hitch as I go by. Sometimes no chains. Sometimes with the tongue sagging down near the road, with no weight transfer. And almost always, especially in windy conditions, you'll see the sway and the hands fighting the wheel! Not a pleasant experience, I expect. If I couldn't have a tag-along that tracked straight and was stable, I'd change to a 5ther, that's for sure.
Dick Wells:)

[SmithvilleD]

Yep, many similar experiences from my farm upbringing. Lotsa thoughtful & also trail-n-error shadetree engineering. Trucks with today's capabilities weren't so common years back.

Read "Trailers - How to Design & Build" by M.M. Smith years back. When discussing tongue length, it suggests so many tailers wind up with tongues shorter than ideal because the most commonly available couplers are a 50 degree angle, (when 40 degrees would better allow for an ideal length tongue). Somewhere along the line, the industry standardized on the 50 degree angle & the cycle continues.

Sorta like the story on red paint being the most common color on barns. In early paints, iron oxide was the cheapest pigment, making red paint cheap. Barns take lots of paint, so farmers chose the most economical paint. Then they sold the most red paint.... and the circle continues :)

[DickWells]

Yes! You may have read in here a couple of weeks back, how I added 39" to my trailer tongue on my previous trailer. In doing so, I got room enough to put my 48" wide ATV across in front, plus kept my electric jack and 30LB tanks. Had a lot of dry mouth, anticipating handling problems, until I towed it. Better handling all around, and even more stable after changing from 600 LB to 1200 LB dual cam bars. Would I recommend it? Probably not, since I wouldn't have confidence that someone else was going to add the material neccessary to be more than sure of the strength of the finished trailer. But, hey, I wouldn't discount the enginuety of some other old farm boy, either. Point is, the longer tongue will usually net you a better handling trailer. I know, I could have said that in the first sentence!
But, then I would have had to stop talking.:o
DW:)

[Inspector]

Reading through these threads I found that no one has said anything about the loaction of the gooseneck ball or the 5th wheel hitch in the bed of the truck. Those two items should always be mounted just ahead of the rear axel in the bed. I believe 2 inchs is what comes to mind. It does the same thing as a load leveling set up for a bumper pull in that it will throw a portion of the pin weight onto the front axel and negating the lateral push in a panic stop or hard braking situation. I have towed a large 5ver in all kinds of places and situations and never had a need to worry about looking at the side of it in a problem. I am also a big fan of using nothing but a DRW truck with the heavier 5vers. The added stability can't be more important.
Denny

[chambie]

When i installed the hitches in my trucks... the hitch manufacturer specified the distance to measure from the rear of the bed to drill the hole for the gooseneck ball. They always end up just ahead of the rear axle. Not sure if it's 2" ahead of it, but it could be.... i'll have to measure it and see.

[DickWells]

That 2" is about what was in the 96 Dodge. Very stable, for the most part with either the heavy old home-made flat bed, or the horse trailer. Still, the DM Duallly handles both with a lot more confidence. The DM has more wheel base, being a CC, as opposed to the XC of the Dodge.
DW:)