M416 Trailer Project

Project started: April 5, 2002
Project finished: April 15, 2003

Acquiring a trailer

I have always been a Jeep nut and really enjoy off-roading and camping. In Oct. of 2001, I bought my third Jeep, a 2002 Wrangler X. I also currently own a 1950 CJ-3A. I was reading up on some Jeep sites and found that many people have used old military "Jeep" trailers to tow behind their 4x4. As I found there were a number of resources on-line for this kind of thing, I decided that I wanted one of my own.

I live in Las Vegas, so the first thing I did was to call all of the military Surplus places in town to see if they had any or knew of places I could try. Most places simply said they did not have any nor did they have any idea where I could find one. I then found one place that gave me the name of "Barstow Truck Parts". Barstow isn't too far away from Vegas and I thought it might be fun to head down there. I found their website and called them. They said they had a couple and that the price was $500. They are only open on Saturday by appointment. I mulled it over for about a week and decided I wanted to at least go take a look at them. I decided I would head down on April 5th of 2002. I called to make my appointment and found that I needed to talk to someone else as he was the "Saturday guy". When we talked, we had a conversation that sort of went like this:

	me:	I want to come down Saturday and look at the M416 trailers you have.
	him:	OK, Now you know what kind of shape they are in, right?
	me:	Well, I was told that they were in good shape and that the only missing piece was the lunette.
	him:	No, they're in worse shape than that.
	me:	Well, I think I'd still like to come look at them. How much do you want for them?
	him:	I'll sell you two for $400.

At this point, I was pretty excited. I was willing to pay $500 for a fixer upper and now I could have two for $400. I found info on the web that these trailers could go anywhere from $450 to $950 depending on condition. So I borrowed a flatbed tandem axle trailer from a friend and hooked it up to my Suburban and headed out to Barstow with my brother Dave and my brother in-law Brian.

We left Vegas at 3:30 am and got to Barstow at about 6:30. After a quick breakfast at McDonald's, we got to Barstow Truck Parts at 7:00 am. He showed us one trailer at the main yard. It was not an M416. It was some kind of ammo trailer and not really what I was looking for. He then led us out to another yard they had a few miles away. This was where the really cool stuff was. A ton of old Military trucks, tanks, trailers, and tires. It was basically a junk yard full of military stuff. Many of the trucks were in various stages of disassembly, some missing motors, etc.

He showed us the first M416 trailer which was sitting almost sideways inside of another trailer. It was beat up pretty bad, but was mostly complete. It had two wheels and tires, complete brake handle and assemblies, lights with broken lens, but was missing the lunette. Next, he showed us two other trailers that were sitting on the ground with no wheels or tires. So the axles were right on the ground. Again, the beds were both pretty beat up. One was missing the landing leg, but had the lunette. The other was missing the lunette, had the landing leg, but was missing the drum/hub assemblies.

I decided to go ahead and get two. I got the first one he showed us that was sitting sideways inside the other trailer as well as the trailer on the ground that seemed more complete (lunette and hubs). I also bought two tires mounted on rims as I knew once I got these home, I'd need some way of moving them both. He charged me $35 per tire and wheel. So he got out the forklift and loaded up the two trailers and my tires and we were headed back to Vegas.

Assessment

The first thing I did after unloading the trailers was to pull the beds off. The nice thing about the M416 is that the bed is removable. Both the earlier M100 and civilian Bantam Trailer had beds that were welded to the frame, making it more difficult to restore. So I removed the beds and set them aside to worry about later.

Both trailers had good and bad parts. As was mentioned earlier, one would have parts the other didn't have and vice versa. I took the first trailer completely apart. I removed the wheels and put the frame up on saw horses. I removed the shocks and threw them away. Next I removed the brake cable assembly followed by the springs and the axle. I removed the lights and then removed and threw away the wiring harness. It probably could have been salvaged, but I knew that I could get a NOS harness to replace it if I wanted to keep the military wiring, etc.

The Frame

I took a wire brush to the entire frame. I could have sand blasted it, but chose not to for a couple of reasons. One, I did not have a sand blaster and wasn't patient enough into looking into renting one, etc. Two, these trailers had been siting in the Mojave Desert in Barstow for years. Any rust on them was mere surface rust and simply scrubbed off. Three, I live in Vegas and rust is not a huge concern here. At this point, I could have used a rust converter product like POR-15, etc, but decided to simply use Rust-Oleum's Rusty Metal Primer. I have had really good success with this primer when used with about 45% paint thinner. I just slosh it all over with a brush and the thinned solution runs into all of the little nooks and crannies and gives you a really good coat to paint on. Then two coats of Rust-Oleum Flat Black to finish it off.

The Suspension

There isn't much to the suspension, two leaf springs and a couple of shocks is all there is. I scrubbed the leaf springs with a wire brush and painted them as with the frame. Thinned Rusty Metal Primer followed by two coats of Flat Black paint. Most of the parts for the suspension can be replaced with parts from 1950's era CJ-3A/B Jeeps per this page. So I bought new shackles, new U-bolts, and new shocks from my local Jeep specialty shop Back Country Products. I am not restoring the trailer to be used in military shows or parades. I am going to use it for myself. So I bought Rancho RS5000 shocks for it. They just look cool.

The Axle and Hubs

The axle took more time. I wanted to make sure that I wouldn't need to worry about towing my trailer and having the bearings burn up on me. I pulled the hubs off the axle and inspected the bearings. They were in surprising shape. I probably could have cleaned out all of the old grease, repacked the bearings and been on my way. Instead, I went ahead and bought new bearings. I reused the old races as they looked great. I also reused the old grease seal as I would have had to special order them. I left most of the brake components alone. The M416 brakes are for parking only, so I was not too concerned about them. I took the drums to have them turned and found that very few places have the proper insert to mount the drum in their lathe. The drum has a huge center hole and most brake places simply don't have anything that will fit it. Back Country Products was able to turn mine, but he did say that they barely fit on his machine. Turning the drums removed the rust and improved the holding ability of the existing pads.Once the drums were turned, I re-assembled the hubs and drum assembly with new grease. I also bought new axle nuts and washers. They are common components for old Jeep axles, and mine were pretty worn. The last washer is not designed to be re-used as it must be bent against the nut to lock the nut in place, so that one had to be replaced and I decided just to replace them all. Once the hubs were re-assembled, I took the wire brush to the whole thing and painted as above.

The Front Assembly

I scrubbed, primer-ed and painted the V-casting, landing leg, safety chains, and front supports and assembled them. I did the same for the brake cable and brake handle assembly. Once assembled, the entire chassis was pretty much complete and I mounted the tires and rims back on which then allowed me to move it much easier.

The Lunette

A subject of much discussion on the various M416 trailer pages is whether to keep or ditch the lunette setup. I looked into this a lot and ultimately decided to ditch the lunette and go with a 2" ball setup. I have seen some where the V-casting is removed and then a hitch is mounted to something bolted in it's place. The solution I came up with was to retain as much of the lunette functionality as possible while still using a 2" ball. I achieved this by cutting off the circle portion of the lunette leaving as much of the shaft as possible. Two half inch square solid bars were cut to the length of the 2" ball assembly. They were then welded to each side of the shaft. The shaft and 2 pieces of half inch bar laid flat up into the 2" ball assembly and were welded into place there. This provided a very solid mount and retained the 360° swivel action that the lunette provided.

Wiring

I mulled over the wiring for quite some time. Should I get a replacement harness and retain the M-Series electrical connectors? Should I replace my worn out lights with the full red lens M-Series lights? In the end, I decided to repair as much as possible. This meant a lot of work just on the light assemblies themselves. Of the 4 tail light assemblies that I had, only three had lens covers and only one had a complete set of lenses. I ordered a replacement lens from Front Line Military. I then set to disassembling each light. The insides were filled with dirt and rust (except for the one with complete lenses). Each bulb holder is suspended by an hour glass looking rubber pieces that act as mini shock absorbers. They are hollow and the wires run from one side to the other through them. I was able to salvage 6 (3 in each light) from the 12 I had. I then decided to re-wire the light as the wires were old and the insulation cracking. To my knowledge, they do not make a rebuild/replace kit for the insides of these lights, although the M-Series connectors and wire are available from Owens Export if you want to retain the military look. I simply bought a 500 ft. spool of 14 Ga. stranded THHN wire from Home Depot for $14 and some bullet connectors. The trickiest part was where the wire contacts the back of the bulb. At that point, there is an insulation washer and a spring on the inside of the socket. The wire passes through the socket, the spring, and the washer and terminates in a large soldered ball shaped like a cup. The first problem I ran into is that my 14 Ga. THHN wire was more narrow than the original wiring so the insulation washer did not stay in place. I resolved this by stripping about a 1/4" of the old insulation off of the original wire and then inserting my wire into the stripped off piece. This gave me the correct thickness. I then stripped the end of my wire about 1/8" and then unwound the strands so that they laid down flat on top of the insulated washer without extending over the sides. I then got out the soldering iron and laid a bead of solder on top of this. The completed wire could then be slipped through the spring and then through the socket and out the back of the light.

I decided not to retain the blackout light features that the trailer had when it was used for military purposes. I had no way to control these lights from a civilian vehicle, so I made two decisions. First, I was not going to restore or re-use the black out stop light which is mounted above the right rear tail light assembly. Second, since I thought the blackout tail lights were cool, I would wire them up to the regular tail lights and have them come on together. So before leaving the tail light assembly, I had tied the black out tail light to the regular tail light. This then left me with two wires, one for the brake light and one for the tail lights. The original setup was grounded through the chassis. Since I did not want to worry about getting the necessary contact throughout the chassis, I decided to run a dedicated ground wire. This gave my the third wire. I ran all three wires out the existing rubber triangle piece that seals the unit off. On the outside of the tail light assembly, I crimped on male bullet connectors

At this point, I decided to just continue with the 14 GA. THHN wire and just build my own wiring harness. I ran three wires from each tail light area all the way to the front of the chassis following the path the previous wiring harness had taken. I replaced the grommets with 3/4" rubber grommets from Home Depot. At the tail light area, I used female bullet connectors to connect to the tail light assemblies. I used 3/8" plastic black wire harness stuff you find at the auto parts store and then used black low profile zip ties to hold it together. Toward the front of the chassis, I combined the two ground wires and two brake light wires to leave me with just 4 wires. These four wires extended out to the front of the V-casting where a 4-wire trailer plug was attached. It's not very military looking, but it looks nice and is functional.

The Bed

Before	After Bending	After Sand Blasting	Finished Bed




		Sorry no image for this
		Sorry no image for this

As you can see from the above pictures, the bed was a mess. There were large bends at the front and rear corners on the right hand side. The right side was then bent inward toward the inside of the cargo area. The front panel was ballooned out like a sail. I took the bed to a couple of body shops and they told me that they would not touch it. One guy told me it would simply tie up his shop and would make his 'body guy' quit.

I have tried beating the bed panels both cold and heated. The big burn spot on the front was from me. My biggest problem was the metal bar/pipe that forms the top outside edge of the box. Since it was bent with the rest of the sheet metal, it held the sheet metal down in the bent position. I posted a message to the Bantam Trailer group asking for suggestions and got this reply from Jay Larson.

I had my father and brother come over to help. We had a 10 foot piece of 2"x2" square steel tube (1/8 inch wall) and a slew of pipe clamps. My dad was very skeptical that we would be able to bend it, so after about 30 minutes of debate, we broke out the tools and started in on it.

We tackled the right side first and clamped the 10' tube to the bed's gunwale tubing with 4x4 blocks of wood in between. We were able to bend it back slowly with the pipe clamps. The tube was bent in and down, so we reset the clamps a few times from the side and then from the top and bent it out and up until it was almost straight.

With renewed optimism, we decided to tackle the back corner which was crushed down. At first, we put a block of wood on the left rear corner and clamped the pipe to it and then cut some two by fours that supported the overhanging tube on the far right side. This did not work. All it did was raise the right side of the trailer as we used the clamp to draw the corner to our 2x2 steel tube. We then tried using a second block of wood in the center. This block acted as a fulcrum and gave us some leverage to pry the corner up. We made some progress there and found that banging on the sheet metal while it was under the pressure of the pipe clamps produced some great results.

To finish it off, we tried yet another approach where we again used the 10' tube across the back held up by one block of wood at the left corner and then at the right corner (the crushed one) we stacked two by fours and four by fours inside the bed until we reached the bottom of the 10' tube. When we used the pipe clamps again, the pressure on the 10' tube pressed down through the blocks to the bed floor. This produced the best results and with the clamps and the hammer were able to lift the corner up. It really worked quite well.

Next, I needed to find some way to clean it up and prep for painting. A friend of mine in town lent me a Craftsman sandblaster. I used my own compressor with it and it simply was not going to strip the entire bed for me any time this decade. My opinion is that this particular tool would be great for small pieces, but not for stripping the entire bed. I tried paint stripper and found that it was messy, but seemed to work OK. It did nothing for the rust. I called a couple of sand blasting places and described it on the phone as a little bit smaller than the bed on a mini-truck. I was given quotes in the range of $400 to $500 to blast the entire bed. I certainly was not going to do that.

My brother-in-law provided the ultimate answer. He had worked for a place that had an industrial strength sand blaster. To make a long story short, for $80, it took them about 15 minutes to strip the entire bed clean. Well worth it in my opinion. Due to the nature of the sand and the blaster that was used, the metal came back pretty rough and pitted. I definitely would not recommend it if you were restoring a Corvette, but for my needs, it was perfect.

To paint the bed, I used the Rust-Oleum Rusty Metal Primer. I hesitated to use this as the instructions indicate that for lightly rusted metal, you should use the Clean Metal Primer, but I ignored it. I then used Rust-Oleum's Sunburst Yellow paint. It is really close to the Solar Yellow that Jeep painted my TJ. I started with a brush, but a neighbor suggested a roller. I used one of those small rollers about 4" wide that you use to paint the trim in your house. It was a lot quicker and worked pretty well. I finished off the bed with some Herculiner. I have used this before with good results. Before I started, I e-mailed them to ask if I could apply it straight to the sand-blasted metal. They replied that I could as long as I first wiped it down with Xylene. As stated above, the sand-blasting left the bed a little rough, so I think the Herculiner should really bond to it.

The Tires

The tires that I got from Barstow Truck were in fairly bad shape. They held air pretty well, but after I took the trailer on my first camping trip (towed it about 350 miles) one tire was about ready to split right down the middle of the tread. I knew I needed to get new tires. My choices were basically as follows:

New NDCC (non-directional cross country) tires and tubes on existing rims
New modern tires on existing rims.
New modern tires and new rims.

In the end, I decided on number one. I think the NDCC tires look really cool and they preserve some of the military feel of the trailer. I purchased tires and tubes from Wallace Wade Specialty Tires and had them mounted by my local Discount Tire Co.

The Data Plate

As you can see from the image above, my original plate is very faded. In fact, the part that was preserved the best is the upper right corner which had been covered in paint. I used paint stripper to remove the paint and that part of the data plate is the most readable. The Sun is no friend to these data plates. Here is the pertinent information from my original plate:

TRAILER, CARGO, 1/4 TON, 2W, M416 FEDERAL STOCK NO. 2330-706-5495
MANUFACTURED BY JOHNSON FURNACE CO., 421 MONROE STREET, BELLEVUE, OHIO
MFR. SER. NO.	6-7⁰⁵⁵	YR. MFD.	1966
MFG. PART NO.	8736302	MODEL	M416
CONTRACT NO.		DA-20-113-AMC-08753(T)

PUBLICATIONS
PARTS LIST		8736302
TECHNICAL MANUAL		9-2330-251-14P
LUBRICATION ORDER		L09-2330-251-12

DELIVERY DATE MAR 1966		INSPECTED MAR 1966

WEIGHTS	EMPTY	CROSSCOUNTRY	HIGHWAY	SHIPPING
Payload	------	500	750	Cubage
Wheels	482	960	1208	159
Ldg Leg	88	110	112	cu. ft.
Total	570	1070	1320

I am not sure if the serial number is supposed to be superscripted as I have it above (you can check the image and see that that's the way it appears on the plate), or if the person stamping it simply did not line it up properly.

Cost Breakdown

Date	Company	Item	Qty	Price	Total Price	Total
04/05/2002	Barstow Truck	M416 Trailers	2	$200.00	$400.00
		Wheel and Tire	2	$35.00	$70.00
		Tax	1	$38.78	$38.78	$508.78
05/15/2002	Back Country Products	Hub wrench Jeep Scout Hex	1	$9.94	$9.94
		RS 5000 Shock	2	$38.99	$77.98
		Spring Shackle Kit	1	$14.90	$14.90
		Spring Shackle Kit	1	$14.90	$14.90
		Axle U-bolt	4	$4.90	$19.60
		HI Nut 7/16 Fine	8	$0.90	$7.20
		Tax	1	$10.48	$10.48	$155.00
05/17/2002	Aztec Industrial Bearing and Supply	Timken LM501349	4	$9.86	$39.44
		Bearing Grease	1	$3.67	$3.67
		Tax	1	$3.13	$3.13	$46.24
05/17/2002	Autozone	Gumout Brake Spray	1	$2.99	$2.99
		Assorted Cotter Pins	3	$1.99	$5.97
		Tax	1	$0.65	$0.65	$9.61
06/06/2002	Back Country Products	Wheel Bearing Washer	2	$0.90	$1.80
		Wheel Bearing Nut	4	$1.90	$7.60
		Wheel Bearing Crimp Washer	2	$0.90	$1.80
		Tax	1	$0.81	$0.81	$12.01
06/07/2002	Back Country Products	Turn Drums	2	$9.00	$18.00	$18.00
06/27/2002	Mv Data Plates (Dan Parmley Jr.)	M416 - Open Mfg. (2) Plate Set - Screened Aluminum (NOS)	1	$25.00	$25.00
		Shipping	1	$2.00	$2.00	$27.00
07/02/2002	Waker Auto and Truck in Hesperia	M416 Fenders (1 Set)	1	$75.00	$75.00
		M416 Hub Dust Cap	2	$7.50	$15.00
		Shipping	1	$10.00	$10.00
		Tax	1	$8.25	$8.25	$108.25
09/30/2002	Front Line Military Vehicles	Taillight lens 00-752-6020	1	$15.00	$15.00
		Lug nuts 00-350-8707	5	$1.15	$5.75
		Shipping	1	$8.25	$8.25	$29.00
10/01/2002	The Home Depot	Grommets (pk of 3)	2	$1.25	$2.50
		Wire Terminal connectors (pk 100)	1	$6.49	$6.49
		Tax	1	$0.65	$0.65	$9.64
03/11/2003	Wallace W. Wade Specialty Tires	700-16LT-C16 STA NDCC	2	$76.95	$153.90
		G/K16 RR15CW H.D. TUBES	2	$12.95	$25.90
		UPS Shipping	1	$44.89	$44.89	$224.69
03/20/2003	Goodfellow Corporation	Industrial Strength Sand Blasting	1	$80.00	$80.00	$80.00
04/11/2003	K-Mart	Herculiner	1	$89.99	$89.99
		Tax	1	$6.52	$6.52	$96.51
04/11/2003	Home Depot	Xylene 1-Qt	1	$4.47	$4.47
		Gallon paint mixer (squirrel)	1	$6.97	$6.97
		Tax	1	$0.83	$0.83	$12.27
04/14/2003	Discount Tire Co	Changeover and Balance	2	$16.00	$32.00	$32.00
04/07/2003	Home Depot	1-qt Rust-Oleum Sunburst Yellow	3	$6.98	$20.94
		1-gal Paint Thinner	1	$2.29	$2.29
		Tax	1	$1.68	$1.68	$24.91

Total					$1,393.91	$1,393.91

I did spend probably another $30 on miscellaneous nuts, bolts, and washers at Home Depot, but since I bought them all at different times, I cannot account for all of them. So if you get anything from this table, it is that the whole thing can be done for under $1500 pretty easily. I could have saved some money in a few places, but opted for buying new components. I re-used the springs, but bought new shackles and U-bolts. The Rancho shocks are overkill, but then again, I think they look cool. I may have been able to salvage the old fenders, but they were pretty hashed and I'm not much of a welder, so I opted to buy NOS fenders. As with most things, there is more than one way to do them. This just illustrates how I approached it.

Conclusion

I have spent a year putting this trailer together. As with most projects, it's not so much the finished product, but the journey getting there. I got to walk through a junkyard full of old military equipment. I leaned how to rebuild hubs (something that I have never done before). I honed my pitiful painting skills. I learned that 14 Ga sheet steel is REALLY HEAVY. Even at $1400, the trailer is still cheap compared to some of the other off-road trailers being built new. Check some of the links below. It was a ton of fun and if you're about to begin a similar project, I wish you the best of luck. Hopefully this page will help in some way.

One More Addition - Spare Tire Mount

On May 29, 2003, I added an under bed spare tire mount. Like many others, my tow rig does not have the same bolt pattern as the trailer. Since I will tow the trailer with both my TJ and my Suburban, converting the bolt pattern of the trailer is also not an option. The only option is to either carry a spare or go spare-less.

This trailer modification is fairly painless and straight forward. I purchased a spare tire mount mechanism from my local junk yard for $5. The donor vehicle was a 1983 Nissan pickup. The trailer has the solid crane loop bars that go across the bottom. These interfere slightly, but not too much. The mechanism is a crank type and on the Nissan, bolted into a frame cross member from the top. My solution was to make a mounting bracket out of 2" x 2" square tubing (which spaces the bracket out from the frame's cross member) and 2" x 2" angle. The angle was cut to roughly 5" across and two holes drilled into the top to receive the mechanism. This was welded to the 10" piece of square tube. Holes were drilled through the trailer frame cross member and into the back of the square tube. I then bolted the bracket to the frame and then the mechanism to the bracket.

To get the tire to sit flat, I had to cut a piece of wood (1" x 2" and as long as the trailer is wide) for the tire to butt up against when tightening. If you look carefully at the last picture, you can see it poking out toward the back of the tire. This is most likely temporary until I figure out a more permanent solution.

M416 Trailer Project

Acquiring a trailer

Assessment

The Frame

The Suspension

The Axle and Hubs

The Front Assembly

The Lunette

Wiring

The Bed

The Tires

The Data Plate

Cost Breakdown

Conclusion

One More Addition - Spare Tire Mount

Links

Reference

FAQ's

Others' Projects

New Trailers

Part Resources

Groups