Topic: Flat Towing help

[jrock]

I want to get some pointers on building a flat tow bar. I could be flat towing my Yota 600 miles. There are hills for the first 100 miles then the rest is flat. I am wondering if I can drill some 3/4" holes (pictures show location) in my 1/4" plate bumper for mounts. I would put a 3/4" grade 8 bolt through these holes to bolt up 1/4" plate that will attached to the flat tow bar. Or I could drill 1" holes and sleeve the holes with a tube about 1.5" long, and still run 3/4" bolts.

Any tips? Ideas? Concerns?

[jrock [OP]]

[RABIDYOTA]

just build 2 brackets that mount where the factory tow hooks would go    and 3/4 would be plenty  you'r hitch pin is only 5/8in   and there is only 1

[Snowtoy]

Looking at the pic above, where the bumper tab is supposed to be bolted to the boxed end of the frame, is the perfect place to locate the tow bar "U"bracket.  If you take a look at a store bought tow bar, there isn't a lot to them, so you don't need to over engineer one.  If this is a one time deal w/the tow bar, it might be cheaper to just rent one.

If that is a 2" drop hitch style receiver under the bumper in the second pic, and is reliable as a recovery point, you might consider using it.  All you would need to do is get a piece of .250 tube, bolt a trailer hitch to it, and figure two points to attach the safety chains to the truck and your done.

[jrock [OP]]

How would you make a single tow bar? How would it be jointed? I always thought the towed vehicle had to have two mounting points so it wouldn't swing around.

[Snowtoy]

How would you make a single tow bar? I always thought the towed vehicle had to have two mounting points so it wouldn't swing around.

There are two types of trailer tongues, the"Y" and "T".  The "Y" style tongue is more common because of its ability to carry more weight, and is a overall stronger design than the "T" style.  Store bought tow bars are designed in the "Y" style because most vehicles don't have a receiver on the front like your bumper does(if that is an actual receiver), adding a straight tongue like this

to the receiver under the bumper would in theory turn your trucks frame into a "T" style tongue.  Going this route all depends on how strong that section under the bumper is, which is something that is impossible to tell from pics.  Also w/o testing it out, it would be hard to say how much side-to-side forces the set-up could withstand, or the wall thickness of the tube that would need to be used to with stand any forces applied during a sway or an emergency stop.  

After thinking about it some more there is quite a bit of weight involved with the truck, so the "T" style tongue may not work on its own, however w/some angle bracing back to the frame(triangulating the tongue) it should be strong enough and would look similar to this,

I always thought the towed vehicle had to have two mounting points so it wouldn't swing around.

Two mounting points wont keep a towed vehicle from wandering around, since it is attached at a single point to the tow rig, and the front tires are free to move on their own(which is needed to make turns).  I would get the measurements of a store bought tow bar length set up for the width of your frame rails and use that length for the length of the tongue, then take it for tow and see how it behaves.

How would it be jointed?

You would need to put only one up/down pivot point behind the hitch and in front of the bracing so you could drop the hitch onto the tow vehicle.

Have you checked craigslist for humbolt county?
http://humboldt.craigslist.org/search/?areaID=189&subAreaID=&query=tow+bar&catAbb=sss  
This one is listed fr $60
http://humboldt.craigslist.org/pts/2149951021.html, if it has the light kit, it will be hard to make your own for less.

[toe]

A flat tow truck won't tow like a trailer where the trailers wheels are a pivot point.

So the tow bar HAS to have a up-down pivot for suspension travel and CAN'T be solidly mounted via receiver tube.

[Snowtoy]

After posting I realized that a fixed tongue would make it rather difficult to hook the hitch to the tow vehicle, so a pivot point behind the hitch needs to be there.  

There is about 45* of up/down pivot with a hitch on a ball(about 15* movement down and about 30* of movement up, would this be enough to cycle the suspension of a towed vehicle just as with a tandem axle trailer, if the tow bar was designed to pivot to attach to the toe rig but then pinned to make the tow bar solid?

Rather than make another post I will correct myself here.
I understand now that it wont, that the relatively short length of the tow bar in relation to the location of the front axle of the towed rig would have the solid bar constantly lifting/puling down the front of the towed vehicle as both vehicle cycled their suspensions during movement.  It is clear that the tow bar couldn't handle this amount of movement, nor the mounts, and it is necessary for it to be able to constantly pivot.

[79coyotefrg]

  snowtoy please don't offer any more "advice"

I want to get some pointers on building a flat tow bar. I could be flat towing my Yota 600 miles. There are hills for the first 100 miles then the rest is flat. I am wondering if I can drill some 3/4" holes (pictures show location) in my 1/4" plate bumper for mounts. I would put a 3/4" grade 8 bolt through these holes to bolt up 1/4" plate that will attached to the flat tow bar. Or I could drill 1" holes and sleeve the holes with a tube about 1.5" long, and still run 3/4" bolts.

Any tips? Ideas? Concerns?

a young friend of mine bought a REESE tow bar and installed it in the exact same place you marked.   on his 250 mile journey he went through a curve in some construction and the tow bar folded up.     The problem (I was concerned it would be but was assured I was Over critical) the attachment points like yours were too close together.   I told him to make them as far OUT as possible and still believe he should have made them near the body mounts.

[junya92toy]

Even if the mounts are ugly going that wide, you can always remove them later

[Snowtoy]

  snowtoy please don't offer any more "advice"

Simply telling me to shut-up doesn't bestow upon me or any other member on this board the wealth of knowledge regarding tow bar/trailer tongue design and function that you must have, and is a reply more suited for Pirate than this Marlin, or is Pirate something this forum is striving to become.  So Omnipotent one, since you claim to have all the answers, please explain what was wrong with the advice I have given? 

If you read my post I stated the best place to attach a tow bar would be where the the bumper tabs attached to the frame in the first picture.  There is nothing wrong with this point,  A buddy flat towed his rig from that same point through mountain passes and winding roads for several years, all w/o issue.  No bending of the bars, no issue with the flat towed vehicle drifting either, even on windy passes or winding mountains at highway speed. 

If you are referring to the single bar idea, JRock asked how it could be done using a single tow bar rather than a triangulated one.  My response was that it might be doable seeing how a "T" tongue is used on trailers that don't have a lot of tongue weight.  However I stated it would have to be something that would need to be looked into, since I was unsure of what type of lateral forces might be applied to a single bar, what size the bar would have to be to counter those lateral forces, and tht it all depended on if that section under the bumper was in fact designed to be a drop hitch receiver.  If it is strong enough to be used as a recovery point, it should be strong enough to flat tow the truck from.

As to the need of the tow bar to pivot up and down, is there any reason for it to do so other than being able to lower it onto the tow vehicle?  Does it need to move any more than the 45* of travel that a standard ball and hitch have in order for the flat tow to work, if the bar is at the same level as the ball on the tow vehicle?  Would it not be similar to a tandem axle trailer, or does a tandem axle trailer pivot enough at the wheels to not need a tongue with vertical pivots in order to cycle its suspension?  These were questions I was asking, something you didn't bother taking the time to answer, if you actually do know the answers.

If my advice is indeed worthless, yours isn't any better, you gave no practical reason as to why you feel moving the ends as far as possible out on a vehicle would be benefitial, other than that your friend's had his fold up.  You didn't even bother to explain how the bars folded up, or why moving them 2" out on each side would have prevented them from folding up under the same conditions?

[yotatough]

I think it needs to have the pivot at the towed truck and stay free pivoting during tow, if not, then everytime the tow vehicle goes up or down it will try to compress the suspension on the towed truck, and bind up a little.   

just my though, please correct me if wrong.

[79coyotefrg]

Simply telling me to shut-up doesn't bestow upon me or any other member on this board the wealth of knowledge regarding tow bar/trailer tongue design and function that you must have, and is a reply more suited for Pirate than this Marlin, or is Pirate something this forum is striving to become.  So Omnipotent one, since you claim to have all the answers, please explain what was wrong with the advice I have given? 

If you read my post I stated the best place to attach a tow bar would be where the the bumper tabs attached to the frame in the first picture.  There is nothing wrong with this point,  A buddy flat towed his rig from that same point through mountain passes and winding roads for several years, all w/o issue.  No bending of the bars, no issue with the flat towed vehicle drifting either, even on windy passes or winding mountains at highway speed. 

YEA for your friend.  was his tow bar "custom made" or rented?

If you are referring to the single bar idea, JRock asked how it could be done using a single tow bar rather than a triangulated one.  My response was that it might be doable seeing how a "T" tongue is used on trailers that don't have a lot of tongue weight.  However I stated it would have to be something that would need to be looked into, since I was unsure of what type of lateral forces might be applied to a single bar, what size the bar would have to be to counter those lateral forces, and tht it all depended on if that section under the bumper was in fact designed to be a drop hitch receiver.  If it is strong enough to be used as a recovery point, it should be strong enough to flat tow the truck from.

NO I went back and reread his post and yours and he did NOT ask if he could use a single bar. he asked "and how would I do that" after you shared your idea.

As to the need of the tow bar to pivot up and down, is there any reason for it to do so other than being able to lower it onto the tow vehicle?

um no, not if both vehicles have the exact same suspension and there are no curbs, dips potholes, or anything other than a PERFECTLY flat plain to be driven on.  since we KNOW that isnt going to happen then the tow hitch MUST pivot up and down at the towed vehicles front end and pivot on the towing vehicles ball hitch so that when pulling into a gas station or your favorite fast food place the solid bar hitch would either lift the drive tires off the ground or lift the front tires of the towed truck off the ground.
 

Does it need to move any more than the 45* of travel that a standard ball and hitch have in order for the flat tow to work, if the bar is at the same level as the ball on the tow vehicle? 

nope, thats all the movement it needs

Would it not be similar to a tandem axle trailer, or does a tandem axle trailer pivot enough at the wheels to not need a tongue with vertical pivots in order to cycle its suspension? 

no, the tandem trailer is very close to one another and the suspension allows the axles to almost float under the trailer.   try raising the tongue of a tandem trailer and see how far you have to lift it to get the front axle off the ground or how low it must go to raise the rear tires off the ground.

These were questions I was asking, something you didn't bother taking the time to answer, if you actually do know the answers.

If my advice is indeed worthless, yours isn't any better, you gave no practical reason as to why you feel moving the ends as far as possible out on a vehicle would be benefitial, other than that your friend's had his fold up.  You didn't even bother to explain how the bars folded up, or why moving them 2" out on each side would have prevented them from folding up under the same conditions?

leverage

[jrock [OP]]

No more bickering!  


From what I have gathered, you want the two mounts (towed vehicle) to be 24" apart. The body mounts are 26" ish apart. So, what if I sandwiched an piece of 90* metal under the body mount. Then bolt a tow bar to that.

[Snowtoy]

79coyotefrg
Thank you for answering my questions in a civil manner, that is all I expected.

The tow bar my buddy used was purchased at an RV dealer, similar to this one,

He welded the "U" brackets to the front of the frame rails w/o issues, even over washed out sections of road where the bars would have been put under twisting motions.

For what it is worth, this is what I had in mind with the two crude drawings above.  It is a purely theoretical design based on the pics of Jrock's truck.  It is only a mock-up, I would have no use for it, so I just used the scrap that I had laying around and tacked it into place. 


It is 52" long overall, the bar(2.5"x2.5") from the pivot to tip is 36"(same length as the tongue on my horse trailer), and the tabs that would bolt to the front of the frame rails are 27.5" apart O/O(same width as the frame on my '91 Toy) or 25.5" center-to-center.  It looks like it would be strong enough once it was made out of .120 and .250 material, it certainly looks like it would be stronger than the typical store bought ones, but it would have to be tested.

[Rocksurfer]

I would not be a good idea to have the hitch on a hard mount. You may think it would act just like a trailer but that is not true at all. A trailer's wheels are centered towards the middle unlike your rig which has wheels at both ends. You need the flexability or the tongue will break free and you'll have a runaway on your hands. The tongue has limited movement up and down.

[Snowtoy]

From what I have gathered, you want the two mounts (towed vehicle) to be 24" apart. The body mounts are 26" ish apart. So, what if I sandwiched an piece of 90* metal under the body mount. Then bolt a tow bar to that.

With more thought put into a design, along w/consideration of what happened to 79coyotefrg's friend, and given your situation of having to mount the bars near your body mounts, this is what I came up with(drawing not to scale),

This design is more like a traditional trailer tongue, and directs the push/pull forces experienced during towing straight at the mounts, rather than at an angle as with this style of tow bar,


Using a plate that is attached at both the body mount and the the front of the frame will distribute the push/pull forces of towing across the front X-member and onto the frame rails, rather than at the body mounts themselves, it would also save you from having to mount the brackets in between the body bushings and the body mounts.  Looking at the pic of your truck, I think 3" .250 flat stock should be about the right size to mount the tow bar brackets to.

The overall length of the tow bar is something that you would have to determine, I am not sure if they should be the same length/longer/shorter than trailer tongues for the flat towed vehicle to track correctly behind the tow rig.

[79coyotefrg]

thats the kind my buddy used that folded up.





it was a Reese brand but i think it was just cheaply made.

[toe]

thats the kind my buddy used that folded up.





it was a Reese brand but i think it was just cheaply made.

Was the steering locked up or unlocked so it could caster in turns?

Locked up steering would put a significant load on the tow bar that it wasn't designed to take.

[79coyotefrg]

nope,  key was in the ignition turned on and the batt cable off.

[HDcruiser]

If you don't mind me asking, where did it fold?? I have the same tow bar as shown in the picture. After reading what you posted, I'm a little concerned with the Reese tow bar.

[Rocksurfer]

I used to run one of those, never had a problem but it was on my lighter than a Toyota Willys and a Samurai.