Drawbar / Ball Mount

[AlexJet]

I build a custom trailer. To connect it to my truck I'll be using a MaxCoupler from Adventure Trailers. I figured out that I need a new Ball Mount for my application, but having trouble finding one.

Data:
Trailer frame height - 27.5"
Vehicle height at hitch level - 21.5"
Height difference - 6" (all measurements were taken from the level ground to lower inner wall of 2" square receiver, so they are accurate)

This means that I need 6" rise Ball Mount. Both truck and trailer were empty at the monent of meausrement. Truck may sit up to 2" lower fully loaded (by itself) while trailer can probably go 3" down after the loading. I'm also thinking of adding airbags in rear coils sometime next year to support the truck level when trailer is fully loaded.

I found a big viriety of 6" drop / 4-3/4 rise Ball Mounts and a few (aluminum) with 6" drop / 5" rise. Note: I need Class III with 1" ball hole.

Which one would you recommend from the list or your option? Do I need forged one for the trailer of 3'000lbs?

HiddenHitch:
- 80240 --- 6" / 4-3/4" 6'000lbs --- $20
- 80383 (aluminum) --- 6" / 5" 8'000lbs --- $80
- 80422 (cushined) --- 6" / 4-3/4" 10'000lbs --- $72

Draw-Tite:
- 40346 --- 6" / 4-3/4" 6'000lbs --- $19
- 40383 (aluminum) --- 6" / 5" 8'000lbs --- $75
- 40422 (cushined) --- 6" / 4-3/4" 10'000lbs --- $72

I need to find one by weekend, so any help is appreciated...

 

[ntsqd]

Within it's elastic strength limit Aluminum has a finite fatigue life. Steel does not.

 

[R_Lefebvre]

Yeah, I wouldn't do aluminum. Just isn't the right application in my mind. You being an aircraft engineer (I think?) might be more comfortable with it.

Do you have a Princess Auto nearby?

http://www.princessauto.com/truck-trailer/towing/ball-mounts/8049364-ball-mount?keyword=ball+mount

http://www.princessauto.com/truck-trailer/towing/ball-mounts/8187452-ball-mount?keyword=ball+mount

Keep in mind, you may not need as much lift as you think, since the ball sticks up from the reciever tube... even if you have a ball on a straight piece of tube, you get about a 3" lift from it. But it depends on how you're measuring, you might have already taken that into account.

Also know, with that much of a drop/rise, and the slop of typical oversize reciever tubes, you're going to end up with a lot of clunking around due to that moment arm. There is a simple solution. Weld a bead on all 4 sides of the ball mount, at the front and back ends of where it fits into the reciever. Not welding it to the reciever, just build up the material, then file the beads down to get a perfect snug fit in your reciever.

 

[ntsqd]

Or do like I did for my bicycle rack as a test for doing the same to the M/C rack. Turn it into an old school bicycle stem with a draw-bolt and a wedge. I did the sliding wedge style, not the split tube wedge style.

 

[AlexJet]

Yeah, I wouldn't do aluminum. Just isn't the right application in my mind. You being an aircraft engineer (I think?) might be more comfortable with it.

Do you have a Princess Auto nearby?

http://www.princessauto.com/truck-trailer/towing/ball-mounts/8049364-ball-mount?keyword=ball+mount

http://www.princessauto.com/truck-trailer/towing/ball-mounts/8187452-ball-mount?keyword=ball+mount

Keep in mind, you may not need as much lift as you think, since the ball sticks up from the reciever tube... even if you have a ball on a straight piece of tube, you get about a 3" lift from it. But it depends on how you're measuring, you might have already taken that into account.

Also know, with that much of a drop/rise, and the slop of typical oversize reciever tubes, you're going to end up with a lot of clunking around due to that moment arm. There is a simple solution. Weld a bead on all 4 sides of the ball mount, at the front and back ends of where it fits into the reciever. Not welding it to the reciever, just build up the material, then file the beads down to get a perfect snug fit in your reciever.

I'm using MaxCoupler which is completely different setup then ball one.

MaxCoupler Video

 

[ntsqd]

Commonly coupler heights are measured and quoted to the top of the ball. Any measurements quoted in literature and anyone that you talk to will be speaking in those terms.

 

[AlexJet]

Commonly coupler heights are measured and quoted to the top of the ball. Any measurements quoted in literature and anyone that you talk to will be speaking in those terms.

 

[REasley]

You can also buy balls with different rises.

Have you looked at adjustable ball mounts? Buyers, Reese, Curt, Rapid Hitch, B&W, DrawTite and Convert-A-Ball and many others make them. Usually in 1" increments.

As for the clunking or hitch rattle. There are anti-rattle or silent hitch pins that will take up the slop.

 

[ntsqd]

sigh. I don't know why I bother.

 

[R_Lefebvre]

I'm using MaxCoupler which is completely different setup then ball one.

MaxCoupler Video

Ok... but you're just looking for a regular drop hitch of some unknown dimension right? Princess Auto has a wide selection with cheap prices and good availability.

Or what else are you asking?

 

[AlexJet]

Ok... but you're just looking for a regular drop hitch of some unknown dimension right? Princess Auto has a wide selection with cheap prices and good availability.

Or what else are you asking?

My calculations gave 6" rise. I can't find any 6" rise. So one of the questions was if anyone knows it. Another was about choosing between Steel, Aluminum or Forged. I also was wondering if shape does make any difference as you can see drop bars with 90 degrees drops and 60 degrees drops.

Anyway, I've ordered Draw-Tite 40346. Will see, may be I'll add some spacers to make it taller or will leave as is. This one was even cheaper then Princess Auto. I've ordered it from CT Motorsports.

 

[R_Lefebvre]

Forged would obviously be the best. Steel would be good, and I myself just wouldn't bother with aluminum. It's just not somewhere I'm concerned about losing weight.

The angle, I don't see any mechanical difference other than if you actually wanted to move the load out a little more, and I don't know why you would. Strength wise, I can't see any difference.

 

['05TJLWBRUBY]

You guys have me curious on this aluminum stinger thing. Years ago, I needed a 6" drop and couldn't get a solid steel one in the weight I needed so I bought an aluminum one. I forget the rating on it, but it was more than enough for my 14K tandem that I regularly pull on it. Been running it for years. Didn't do it for weight savings at all, got it out of necessity as it was the only one rated at the time as they were out of steel that day. Never had an issue with it under the loads of the that rig which is far more than these Jeeps or Rovers or what have you will ever dream of pulling off-road. Is there something I'm missing or should be concerned with???

Unless there's something really bad I'm missing, my experience has been good with them-pulling bigger loads than what these rigs will ever see. Not saying to rush out and buy an aluminum one, but if it's your only option and you need it, I wouldn't NOT buy it either and miss a trip just because you want to hold out for a steel version. Mine's been working fine for a good number of years now.

Best of Luck,

Mike

 

[ntsqd]

Within it's elastic strength limit Aluminum has a finite fatigue life. Steel does not.

What I'm saying here is that within the limits of bending something short of the point where it will no longer spring back into shape, mild steel has no fatigue life limit. OTOH even within that spring-back limit aluminum does have a fatigue life limit. Normal design for aluminum calls for 1/2 million cycles before failure. I've no idea what those aluminum draw-bars are designed to, and I really have no intention of finding out.


One thing that the angled version does offer is a small increase in the weld bead length. Near any limit that might be important.

 

[R_Lefebvre]

Yeah, I don't *know* that there is anything wrong with it, and it's *probably* fine. I just wouldn't really want to take a chance with it. If it was the only one I could find, and from a reputable manufacturer, yeah, I'd probably go with it and try to keep an eye on it. But I bet that even though it may be rated to tow the load, as always they have big disclaimers on that rating about inspecting your equipment, etc.