Custom trailer for a bobcat 743

[dmason]

I'm taking delivery of a 1990 743 and I'm revamping an equipment trailer with new tandem axles. It is 7" X 12" and I need to figure out where to put my spring hangers for the 743. I was told that most of the weight was toward the back so I figured that its CENTER OF GRAVITY with a bucket would probably put it right at about the inside of the back tire. I will be towing it facing forward so that would put the CENTER spring hanger a little more directly under the rear tire to allow for adequate tongue weight. I only have an extra 2 ft to play with so it needs to be very close. Any thoughts ?? thanks

 

[Tazza]

You will really need to experiment to see where it looks good on your truck's springs for tongue weight. Most of the weight is indeed in the rear of the machine.

 

[[email protected]]

You will really need to experiment to see where it looks good on your truck's springs for tongue weight. Most of the weight is indeed in the rear of the machine.

i use a 12' trailer for my machine. it's just too small. it fits maybe the machine with one bucket, but barely. be careful driving onto the trailer.....really should be backed on unless you have weight in the bucket.

 

[dmason]

i use a 12' trailer for my machine. it's just too small. it fits maybe the machine with one bucket, but barely. be careful driving onto the trailer.....really should be backed on unless you have weight in the bucket.

Tom Can I get a side picture of your set up? Much appreciated

 

[mmsllc]

Tom Can I get a side picture of your set up? Much appreciated

First off, I am very surprised to see that anyone would give axle placement much thought, but that is HUGE of you to consider it. (I am assuming that you have to remove / change an axle anyways.) Nevertheless, the most ideal tongue weight of any trailer is a mere 10% of the trailer weight. The other 90% should be fully supported by the running gear (tires, axles, springs, etc.). I understand that you don't want the majority of the weight odd this 743 to behind the rear of the axles or the center bracket. But, how far back will that require your axles to be set? If they are too far back, it will require you to swing much wider than with a normal trailer with an average placement. Another note worthy question is, how will this trailer handle other loads if you are not moving the 743? When I built my first 6x12 trailer, I was advised by a trailer builder to move the center bracket 12" past the center line of the trailer body; not including the tongue. I went an extra 3" past that just to be safe & increase tongue weight / down force on the rear axle of the towing vehicle. When I was done, it rode just perfect / not too tongue heavy as long as I placed the load at the trailer's center line of the body. I would only caution you not to place the axles too far rearward. What are you towing this trailer with? If you are using a heavier truck (3/4 or ton), then you may not notice too much extra tongue weight. I'm going to try to post a hell of a heavy trailer for a 3/4 truck. I will post it under this thread if it lets me. The reason I want to post it is because is because it was VERY tongue heavy, even with the load being placed over the center line of the trailer. Every single pot hole had the front end of my truck pulling off the road = it was kinda doing a see-saw thing with the rear axle being the fulcrum.

 

[dmason]

First off, I am very surprised to see that anyone would give axle placement much thought, but that is HUGE of you to consider it. (I am assuming that you have to remove / change an axle anyways.) Nevertheless, the most ideal tongue weight of any trailer is a mere 10% of the trailer weight. The other 90% should be fully supported by the running gear (tires, axles, springs, etc.). I understand that you don't want the majority of the weight odd this 743 to behind the rear of the axles or the center bracket. But, how far back will that require your axles to be set? If they are too far back, it will require you to swing much wider than with a normal trailer with an average placement. Another note worthy question is, how will this trailer handle other loads if you are not moving the 743? When I built my first 6x12 trailer, I was advised by a trailer builder to move the center bracket 12" past the center line of the trailer body; not including the tongue. I went an extra 3" past that just to be safe & increase tongue weight / down force on the rear axle of the towing vehicle. When I was done, it rode just perfect / not too tongue heavy as long as I placed the load at the trailer's center line of the body. I would only caution you not to place the axles too far rearward. What are you towing this trailer with? If you are using a heavier truck (3/4 or ton), then you may not notice too much extra tongue weight. I'm going to try to post a hell of a heavy trailer for a 3/4 truck. I will post it under this thread if it lets me. The reason I want to post it is because is because it was VERY tongue heavy, even with the load being placed over the center line of the trailer. Every single pot hole had the front end of my truck pulling off the road = it was kinda doing a see-saw thing with the rear axle being the fulcrum.

I am pulling it with a 1500 suburban with tow package and weight distribution hitch. This trailer was an old mobile home frame. 6" I beam. I'm installing (2) 5200 pd dexter axles under slung and going with 15" r 225 tires. On top of the frame I'm welding a dump bed together from scratch. the tongue to bed is 4' and the bed is 12'. I was thinking the 743 with bucket being 10 ft long would put the center of gravity at 7' 5" toward the back of the dump bed as it faces forward with a foot or so to spare front and back for tweeking . After reading more about trailering everyone suggests to back the machine on so now I'm second guessing my measurements because if I do that then its going to be way too tongue heavy ???

 

[mmsllc]

I am pulling it with a 1500 suburban with tow package and weight distribution hitch. This trailer was an old mobile home frame. 6" I beam. I'm installing (2) 5200 pd dexter axles under slung and going with 15" r 225 tires. On top of the frame I'm welding a dump bed together from scratch. the tongue to bed is 4' and the bed is 12'. I was thinking the 743 with bucket being 10 ft long would put the center of gravity at 7' 5" toward the back of the dump bed as it faces forward with a foot or so to spare front and back for tweeking . After reading more about trailering everyone suggests to back the machine on so now I'm second guessing my measurements because if I do that then its going to be way too tongue heavy ???

Two things come to mind! They are: ** 1.) Well, towing with a 1500 suburban is a good way to kill the "10-bolt" rear axle in it. They really are not that heavy duty for the towing arena; despite all of the commercials that state other wise. Your rear leaf springs are tuned to providing a comfortable ride versus having more of a heavy hauling ride in mind. You can also step up to a stronger 3/4 ton axle & leaf springs. ** 2.) The other thing is to possibly rent a dump trailer that is close to what you are thinking of building. That way you can try it out before you commit to it. Then you can also try pulling it on forwards & backwards before welding anything together. If you find that you like the combination, then you can measure where they set their axles at.........

 

[dmason]

Two things come to mind! They are: ** 1.) Well, towing with a 1500 suburban is a good way to kill the "10-bolt" rear axle in it. They really are not that heavy duty for the towing arena; despite all of the commercials that state other wise. Your rear leaf springs are tuned to providing a comfortable ride versus having more of a heavy hauling ride in mind. You can also step up to a stronger 3/4 ton axle & leaf springs. ** 2.) The other thing is to possibly rent a dump trailer that is close to what you are thinking of building. That way you can try it out before you commit to it. Then you can also try pulling it on forwards & backwards before welding anything together. If you find that you like the combination, then you can measure where they set their axles at.........

Now why didn't I think of that! that's why I love forums like these other users experience and common sense. Instead of trying to over think it I just need to try a few other trailers and take that into consideration when building mine. Thanks Again

 

[mmsllc]

Now why didn't I think of that! that's why I love forums like these other users experience and common sense. Instead of trying to over think it I just need to try a few other trailers and take that into consideration when building mine. Thanks Again

It helps to have one (a trailer that is already built) to look at. In this case, it should not be too hard to try one out before having to buy it. I would imagine Craigslist might even have a listing for a trailer like what you are thinking of. Or a rental equipment place should for sure. These forums are great for a ton of reasons. I should have also mentioned that 1/2 ton trucks also have a much lighter duty transmission. They are really overrated by the manufacturers. A good 3/4 ton / heavier / "8-lug" truck would be a far better towing vehicle. Then there is the brake system to consider. EVERYTHING is better for towing in the "8-lug" world.