Tow hitch receiver upgrade for a motorhome

[elbundi]

I was going to wait until I had gotten a little further ahead before starting a thread, but Keyair asked so here goes. It's probably a good idea anyway at this point to get input from the forum before doing anything that cannot be easily undone.

It all happened one dark rainy evening with a mail box about 3 yrs ago, and the bumper is only half the story! See my posting on rear window repair.


Guilty


Fixed with a heavy duty strap and ratchet

Then a year or three later decided to remove the bumper and see if I could make it look better. Of course with any can of worms!


Bumper off.




Need to straighten this out somehow.


The wheel cover and rear passenger side banana wrap needs attention too which I’ll save for another day. I removed the old insulation and will replace that later too.


A previous owner had pulled something more than the 2,000lb limit and did this.


I tried to coerce it back with a bottle jack. But that didn’t work out. So off it came.


Two welds on either side needed the angle grinder as well as the two well-rusted bolts holding it to the sub chassis.


With a cold chisel and angle grinder the cross member finally came off. I reckon with all that hammering I knocked off about 10lb’s of rust.


I tried hard to leave the remaining chassis straight and in tact, but life’s not perfect.
I’ll use the bottle jack again to see if I can straighten them out. May also get a couple of metal plates and try to sandwich them together with some clamps. Always open to ideas on this as well as how to straighten the bumper.





I bought a 4ft draw tie locally, one like this
Trailer Hitches - Draw-Tite - Custom Trailer Hitch Products and Hitch Accessories for $58.95.
3ft is plenty enough though so cut off the end.

Then went to our local Ameristeel warehouse and bought a ‘short’. This was an 8’10” left over from some job (20ft minimum on un-cut steel). The steel piece measures 4” wide, 2” tall, 3/16th thick and was cut to 3’3.5”, then 2’10” and then the remaining piece plasma cut in two down the center length. This came to $48.15

Also purchased some 3/8th grade 8 nuts bolts, and washers for about $4 from tractor-trailer, and a can of primer for another $4.





Fired up 3DS MAX and came up with these rudimentary drawings.


Existing hitch


New design


The underside

The new hitch will be bolted onto the frame using the grade 8, 3/8” bolts at either end of the 34” piece and using the same locations for the bolts on the 39.5” piece. Then will take it to the welders.

Still thinking through some other things though. The existing wiring is good for a four-pin connector. Can I daisy chain off the tag brakes wire and use this to power trailer brakes through a 7 pin connector?

The close proximity of the fuel tank worries me for welding. Thinking some sort of temporary spark barrier may help.

I’m also not 100% on the exact location of the welding spots yet, and where to put the support diagonals too.

Here are a couple of tow hitches I found on the forums that have been beefed up by other users. I’m sure there are more out there but they’re all over the place in many different threads.







I’m using this last one as a template for mine.

That’s the story so far. I’m kind of slow so apologies ahead of time if it’s a week or so before posting any more progress.

[AirRowan]

This is what i did and it seems to be working.

[Keyair]

Wow Elbundi!
You are the man!
AirRowen, that looks good too!
Great thread, and great info!
I got that plus lots else to do to mine as you can see.....



Now, I was thinking about a couple of things here...
I am concerned about the rear of my gas tank... AirRowen, like others has the tube bars to do that job, mine has nothing.
I was also looking at all that wasted space between the Gas tank and tow hitch.... maybe I can build a platform there to mount my water tank, instead of under the queen bed...

[Gypsy Jo]

Under the Argosy MH forum the thread http:www.airforums.com/forums/f310/receiver-hitch-frame-repair-73893 projector did a nice job on his hitch .
I know the mh are different but could give you guys some ideas.
That link didn't work for me but if you go to Argosy motorhomes its about half way down the page .
receiver hitch,frame repair is the name
Jo

[AirRowan]

I would not tee into the tag brakes. Thats what my friend the RV mec sead. The one for tag works on inertia u want one that u can adjust and self apply in those spots when u do not wont to waight for the 2 to 4 second ramp up!

[elbundi]

Originally Posted by AirRowan

This is what i did and it seems to be working.

I'd seen your set-up before but couldn't find the link again. Looks very sturdy. Did you have a separate brake controller installed? What all do you tow with your MH?

Here's the Argosy hitch repair thread

Thanks Keyair. Hope to see your efforts soon. Those wheels under yours look kinda abused. Do you think they were factory installed?

[Keyair]

Yeah, thos wheels are TOAST!
Factory?
No Idea!
Based on the damage, I want to have a skid plate or castor back there!

Questions for you...
The odd shaped plates(the one that my mangled wheel frame is bolted to) that the rearmost original hitch and crossmember was bolted/welded to... that are attached to the Chassis... do they unbolt?
In other words, If I unbolt that plate from each side would the tow hitch Assembly come off?

Found another thread here with Pics...
http://www.airforums.com/forums/f160...elp-40494.html

[elbundi]

Originally Posted by Keyair

Yeah, thos wheels are TOAST!

Questions for you...
The odd shaped plates(the one that my mangled wheel frame is bolted to) that the rearmost original hitch and crossmember was bolted/welded to... that are attached to the Chassis... do they unbolt?
In other words, If I unbolt that plate from each side would the tow hitch Assembly come off?

If you could persuade the bolts to come off then I don't see why not. Would make working on the wheel thingies a lot easier.

[elbundi]

Finally had a couple of hours the other evening.
Decided not to beat the crap out of the end piece of metal and moved the location of the first cross member forward 4" to keep it level.







Still some more grinding on the second cross member so that the draw tie will be level.

[AirRowan]

Originally Posted by elbundi

I'd seen your set-up before but couldn't find the link again. Looks very sturdy. Did you have a separate brake controller installed? What all do you tow with your MH?

Here's the Argosy hitch repair thread

Thanks Keyair. Hope to see your efforts soon. Those wheels under yours look kinda abused. Do you think they were factory installed?

I tow a 25foot lobster boat that has surge brakes but i plan on putting electric on the other axel. I have 2 brake controlers i will post a pic of them when i get home.

[Tks18]

/tmp/System.pdf Not sure if this pdf will load, but the question in in the pic

[Tks18]

Towing a honda Element 3500 lbs

[AirRowan]

Can you post some pics of it and what the welds look like?

[Tks18]

Thanks so much for the interest. Here are the pics of what we have. We will be drilling and pinning or bolting today. Seems similar to what you have done only without the angles.
Tom and Warren

[elbundi]

Took a day off work last week and went to a local welder to get the this stage of the new hitch complete. It's not rocket science or as complex as a PSD transplant but the process is certainly a personal lesson

While the three pieces were still bolted in place a couple of spot welds were done to keep things true when we removed it from the main chassis.














The welder at his press







Looks a bit blobby but I'm sure it's a good weld











Painted with rubberize underside paint. May buy some more and do the whole rear underside. You never know when someone will look

I reckon it'll hold for a 5-6000 lb tow with 500-600 lb of tongue weight. Good for a car on a trailer, a small to medium size boat or a couple of horses in a trailer.

I intend to add heavy duty hooks to hang trailer chains and add a 7 pin plug holder too.
Then on to wiring a new brake controller. Looks like electric is the way to go.

[Smartstream]

Well I tore into the back of my moho today to take a look at the hitch. You guys got it easy compared to my 280.

The hitch cross member hangs from the ends of the frame rails held by three 1/2" bolts on each side. It was a real joy getting to those six bolts. The hangers and end fittings are formed from 1/4" mild steel. The rest of the cross member is formed from 3/16" mild steel with lots of 2" lightening holes. The receiver itself looks fine, it's just hanging from a lot of nothing.

The real fun part is the tanks hang below and around the frame rails. If I pull the tanks I can beef up the frame rails but I can't really tie the hitch to anything forward because of the tanks. In the pictures you can see the bottom end of the rails where the tank hangers are attached. You can also see the connector they put in for the trailer light plug which is mounted under the spare tire mount. Unfortunately the connector won't fit through the hole in the rear panel so you have to cut the wires anyway.

For now I've got some 1/4" flat stock so I'll weld in doubler plates on the horizontal and vertical part of the cross member and then weld in a plate across the front side to form a triangular box. Should be a lot stronger than the existing but still limited by the tanks in the middle of everything.

I'm open to suggestions if anybody has any ideas.

Cheers, Dan

[dadstoy]

Hi Dan. I'm very interested in what you do. I would like to do same to my 280. I would like to pull an ATV trailer.

[Keyair]

Interesting to see the differences Dan.
I see no reason why that bar can't be plated with the 1/4", as you planned and then add additional gussets to cross stiffen the receiver to the bar.
Its tricky to imagine how the gas tank/tanks are compared to the longer tailed 345's etc, but could you lengthen the side plates all the way forward, to double the chassis rails and bolt thru. Then maybe put a crossmember in fwd of the tanks, so creating a boxed stiffening?

[Smartstream]

Originally Posted by Keyair

Interesting to see the differences Dan.
I see no reason why that bar can't be plated with the 1/4", as you planned and then add additional gussets to cross stiffen the receiver to the bar.
Its tricky to imagine how the gas tank/tanks are compared to the longer tailed 345's etc, but could you lengthen the side plates all the way forward, to double the chassis rails and bolt thru. Then maybe put a crossmember in fwd of the tanks, so creating a boxed stiffening?

Keyair I took another picture today to try to show the problems.

First the cross member is hung on the end of the frame rails. There is only 3" of rail extending past the black tank. The three bolts on each side form a triangle about 2" on a side. The crossmember hangs from a formed 3"x1"x1/4" thick angle. From the center of these bolts, the center of the receiver is down about 10". The lever arm formed by a ball mount that far from the three bolts on the end of the frame rails is tremendous.

Beefing up the frame rails might aid in carrying more tongue weight vertically but won't relieve any of the twisting on the crossmember. It really needs to be boxed in with some bracing from the bottom of the receiver forward on the chassis. But then you come back to the tanks. The bottom of the tanks is nearly at the center of the receiver. Any brace would have to extend about 34" forward to clear the tanks and would hang low enough to drag everywhere.

If you look closely in the other pictures you will see two tabs under the receiver that held a 3" drag roller. There was also two large casters mounted on the bottom of the crossmember. Over the years dragging these wheels has twisted the crossmember enough to crease the rear panel with the top of the spare tire mount. I'm removing all of these wheels to gain about 3 1/2". Maybe I can eliminate most of the dragging and if not a steel plate on the bottom of the receiver will last a long time. I even thought about cutting off the receiver and moving it up a couple of inches closer to the bumper but that would really put the tanks in harms way.

I don't expect to tow a 10,000lb trailer but the way it is now it worries me to even pull my 1600lb smart.

Dadstoy I hope this answeres some of your questions.

I'll post some more pictures when I finish beefing up the crossmember.

Cheers, Dan

[elbundi]

Dan

Take a look at these two pictures and see if using braces on the two end pieces to the main chassis could be fabricated and then replace your swiss cheese cross member with something sturdier that will hold the receiver tube higher up

Originally Posted by Smartstream

Well I tore into the back of my moho today to take a look at the hitch. You guys got it easy compared to my 280.

The hitch cross member hangs from the ends of the frame rails held by three 1/2" bolts on each side. It was a real joy getting to those six bolts. The hangers and end fittings are formed from 1/4" mild steel. The rest of the cross member is formed from 3/16" mild steel with lots of 2" lightening holes. The receiver itself looks fine, it's just hanging from a lot of nothing.

The real fun part is the tanks hang below and around the frame rails. If I pull the tanks I can beef up the frame rails but I can't really tie the hitch to anything forward because of the tanks. In the pictures you can see the bottom end of the rails where the tank hangers are attached. You can also see the connector they put in for the trailer light plug which is mounted under the spare tire mount. Unfortunately the connector won't fit through the hole in the rear panel so you have to cut the wires anyway.

For now I've got some 1/4" flat stock so I'll weld in doubler plates on the horizontal and vertical part of the cross member and then weld in a plate across the front side to form a triangular box. Should be a lot stronger than the existing but still limited by the tanks in the middle of everything.

I'm open to suggestions if anybody has any ideas.

Cheers, Dan