My M416 Build Thread

[CoastalDefender]

I found a 3500 lb axle at http://www.trailerpart.com/35ktraileraxle.htm that came in a variety of bolt patterns and was available in 1" increments. Complete axle and hubs for $105. I went with the 6 on 5.5 pattern and bought a set of wheel adapters from http://www.ezaccessory.com/Wheel_Adapters_s/25.htm to convert them to the 6 on 4.5 that I needed to match my truck. I went with a 60" axle and with the 1.5" adapeters that will give me a face to face length of 63". The wheels I ordered are 16x8 have a 5" backspace, and the axle required a minimum overhang of 11" so this will get me right on the money.

They're giving me the business of "only odd-number sized axles. 59", 61", 63", etc"

I have the same truck as you. I plan on using stock wheels, they have a 4.5" backspace. So I would think a 61" axle w/ 1.5" spacers (6x5.5->6x4.5) plus the stock wheels as 4.5" backspacing would give the same width as you have? Or at least damn close. Am I way off base here?

 

[bigdog]

They're giving me the business of "only odd-number sized axles. 59", 61", 63", etc"

I have the same truck as you. I plan on using stock wheels, they have a 4.5" backspace. So I would think a 61" axle w/ 1.5" spacers (6x5.5->6x4.5) plus the stock wheels as 4.5" backspacing would give the same width as you have? Or at least damn close. Am I way off base here?

so the only differance would be the .5" of backspacing on each wheel, so 1" differance total. But does that mean 59" or 61"? It's late, but I think 59" is what you want. The key for me was to have 11" from where the axle and spring mounted to the center of the mounted wheel. I don't think there is any harm in being a little longer as far as the load goes, but I did add a 4" section to my fenders and the wheels still stick out. So it's a balancing act between getting them tucked in and being safe.

BTW- I also have since dropped down from a 295 to a 265 on the trailer tires. After cruising a couple hours on the highway I felt that a smaller tire might track better, but they are close enough to all still look uniform.

 

[CoastalDefender]

so the only differance would be the .5" of backspacing on each wheel, so 1" differance total. But does that mean 59" or 61"? It's late, but I think 59" is what you want. The key for me was to have 11" from where the axle and spring mounted to the center of the mounted wheel. I don't think there is any harm in being a little longer as far as the load goes, but I did add a 4" section to my fenders and the wheels still stick out. So it's a balancing act between getting them tucked in and being safe.

BTW- I also have since dropped down from a 295 to a 265 on the trailer tires. After crusing a couple hours on the highway I felt that a smaller tire might track better, but they are close enough to all still look uniform.

Got it. Yes, I would rather have the new wheel/tire combo nice and tight inside and close to the frame. So I'll step in with a 59" axle, and since the tires I will run are 265/75r16's it should end up perfect, no?

Would 57" axle bring me too close to the frame, or would I be fine there too? I would like to get them as close as possible, without endangering them.

 

[bigdog]

Got it. Yes, I would rather have the new wheel/tire combo nice and tight inside and close to the frame. So I'll step in with a 59" axle, and since the tires I will run are 265/75r16's it should end up perfect, no?

Would 57" axle bring me too close to the frame, or would I be fine there too? I would like to get them as close as possible, without endangering them.

We are assuming that your stock axle and mine are the same to begin with (which they probably are). The stock M416 axle was 58.75 in, but the M416A1 was 61.62 in. Just to be safe measure your current axle with wheels off and drums on. The length from the drum face to drum face should be roughly the same as the length from spacer face to spacer face. So you can subract 3" from the current axle length (to backout spacers) that would maintain the stock length of the axle. I'm not sure what the backspace on the milspec wheels are, but with the wheels mounted you should be able to see how much clearence you have from the frame. If you adjust for the increased backspace and the wider tire then you can see how much clearance there would be. The stock tire is 7x16 and you are going to roughly 10.5" so you've got an exta 3.5" of width with (depending on backspacing shift) at least 1.75" pointing inward.

According to the M416 manual, the stock wheel is 16x4.5 and you are going to a 16x8. But the truth is these stock wheels are pretty flat in the front so there could be close to 4" of backspacing, but that will be something you need to measure.

The other requirement was the overhang. And I wish that I could find where i saw that. I looked on their website but can't find it. You may have to check with them on what their minimum is.

 

[bigdog]

The 500# payload is to be able to float,, on road these were rated at 1250# or so,, off-road 750# and flotation 500#.. or about that..

I don't know where you found that info. What the M416 manual says is this:

Capabilities and Features.

1. Maximum payload (cross-country and highway): 500 lb (227 kg).
2. Angle of departure: 20°.
3. Towing vehicle: ¼- or ¾-ton utility truck.
4. Towing speeds (maximum):

(a) Highway: 55 mi/h (88 km/h)
(b) Improved roads: 50mi/h (80 km/h)
(c) Cross-country: 30mi/h (48 km/h)​

 

[CoastalDefender]

We are assuming that your stock axle and mine are the same to begin with (which they probably are). The stock M416 axle was 58.75 in, but the M416A1 was 61.62 in. Just to be safe measure your current axle with wheels off and drums on. The length from the drum face to drum face should be roughly the same as the length from spacer face to spacer face. So you can subract 3" from the current axle length (to backout spacers) that would maintain the stock length of the axle. I'm not sure what the backspace on the milspec wheels are, but with the wheels mounted you should be able to see how much clearence you have from the frame. If you adjust for the increased backspace and the wider tire then you can see how much clearance there would be. The stock tire is 7x16 and you are going to roughly 10.5" so you've got an exta 3.5" of width with (depending on backspacing shift) at least 1.75" pointing inward.

According to the M416 manual, the stock wheel is 16x4.5 and you are going to a 16x8. But the truth is these stock wheels are pretty flat in the front so there could be close to 4" of backspacing, but that will be something you need to measure.

The other requirement was the overhang. And I wish that I could find where i saw that. I looked on their website but can't find it. You may have to check with them on what their minimum is.

No, I've got a M101CDN, so most parts are the same size as the 416, but I'm certain there are differences (like the weird canadian bolt pattern). I'll have to measure the axle.

What's "overhang"?

 

[bigdog]

No, I've got a M101CDN, so most parts are the same size as the 416, but I'm certain there are differences (like the weird canadian bolt pattern). I'll have to measure the axle.

What's "overhang"?

it's when your belly hangs over your belt :xxrotflma

but seriously, Overhang for axles with single tires is the distance from the centerline of the spring to the centerline of the tire. If I remember correctly these axles were supposed to have a min of 11" and a max of 15" of overhang. Be sure to ask for verification, it used to be on their website.

 

[Cruiser]

I don't know where you found that info. What the M416 manual says is this:

Capabilities and Features.

1. Maximum payload (cross-country and highway): 500 lb (227 kg).
2. Angle of departure: 20°.
3. Towing vehicle: ¼- or ¾-ton utility truck.
4. Towing speeds (maximum):

(a) Highway: 55 mi/h (88 km/h)
(b) Improved roads: 50mi/h (80 km/h)
(c) Cross-country: 30mi/h (48 km/h)​

That info was on the data plate on my 67 stevens, m416 and same on my 66 m614(same just different#).. as the design there were contracted thru the gov to meet certain specs.. the main one was to carry 500# off-road and at"speed" or at an off-road speed the m38 and the m151 could go.. Also it was to float with 500# so when the m38 or m151 would be driving thru the river,lake, pond, what have you the trailer would float higher than the tow vehicle and keep the axles from snagging on the bottom and possibly causing the tow vehicle to get stuck.. also it would keep the supplies dry.. That is why no tailgate.. If you do some searching on the history of the m100, mtb, m416 there is a lot of info online about the trailers,, and how during WWII bantam in Butler Pa got to build them instead of the jeeps they designed due to the company being so small.. the US. Gov. gave the jeep contracts to bigger companies that they trusted could supply the amount of jeeps they needed,, and gave Bantam a trailer contract as a way of saying "I'm sorry your small"..
Check out g503.org for more vintage trailer details,, but dont talk about modding one over there..

 

[RAZORBACK]

M416 axle

Do you know if the company you bought your axle from, offers one that will let you use the factory parking brake?

it's when your belly hangs over your belt :xxrotflma

but seriously, Overhang for axles with single tires is the distance from the centerline of the spring to the centerline of the tire. If I remember correctly these axles were supposed to have a min of 11" and a max of 15" of overhang. Be sure to ask for verification, it used to be on their website.

 

[Martyn]

Do you know if the company you bought your axle from, offers one that will let you use the factory parking brake?

You can get electric brake backing plates and hubs equipped for a parking brake for 3500 lb axles with #84 spindles. They are a special order part, I have the part numbers if you want them e mail me martyn at adventuretrailers dot com.

If you already have the parking brake hardware it's just a matter of doing a little fabrication on the end of the cable. If you don't have the handle and cables then it's a lot of work and $$

 

[CoastalDefender]

Where did you get that Pioneer Rack at? I was holding off on getting it for my setup, but... Well frankly its looking like that's the best route. :sombrero:

 

[bigdog]

Do you know if the company you bought your axle from, offers one that will let you use the factory parking brake?

that is what I was originally looking for, but once I could not find my lug pattern i need to replace brake drums with wheel adapters. The other challenge with the stock drums is the spindle size, so you will probably need to replace the drums and that gets you into electric brakes.

Where did you get that Pioneer Rack at? I was holding off on getting it for my setup, but... Well frankly its looking like that's the best route. :sombrero:

ebay. There was a guy selling a bunch of them. I am real happy with it, did have to do a little cutting to get it to fit where I wanted it, but it's really the perfect size for that back wall. Here's one now:

http://cgi.ebay.com/ebaymotors/Mili...rts?hash=item35a33705a1&_trksid=p4506.c0.m245

The bigger challenge was finding the tools. Everything has gone plastic, so finding a little wooden d handle shovel was a lot harder then i expected. In the end I had to trim the shovel handle and the pick axe handle to fit.

 

[bmonday]

I went the Pioneer rack direction as well:

I had to cut down the shovel, as others have also had to do, but I also had a heckuva time finding a pulaski with an easily removable head. Come to think of it, a properly sized axe was a PITA to find too!

My build thread is here: http://www.expeditionportal.com/forum/showthread.php?t=17866

Oh, when shopping for a Pioneer Tool Rack, make sure you get one with all the straps. Those are somewhat unique and can be hard to source. I got mine from eBay also, but from this guy in Texas: http://stores.shop.ebay.com/Austin-Aviation-HMMWV-Surplus__W0QQ_armrsZ1 There was a piece missing on the first one he sent, and he sent me a second right away when I emailed him, free of charge, ad told me to keep the first one too. Stand-up guy.

 

[telwyn]

license plate?

The Pioneer Racks look like a great use of space on the back of the trailer, but where do you guys mount the license plate?

EDIT: I see one of you hung it (precariously?) from the bottom of the bumper.

 

[bigdog]

I went the Pioneer rack direction as well:

I had to cut down the shovel, as others have also had to do, but I also had a heckuva time finding a pulaski with an easily removable head. Come to think of it, a properly sized axe was a PITA to find too!

My build thread is here: http://www.expeditionportal.com/forum/showthread.php?t=17866

Oh, when shopping for a Pioneer Tool Rack, make sure you get one with all the straps. Those are somewhat unique and can be hard to source. I got mine from eBay also, but from this guy in Texas: http://stores.shop.ebay.com/Austin-Aviation-HMMWV-Surplus__W0QQ_armrsZ1 There was a piece missing on the first one he sent, and he sent me a second right away when I emailed him, free of charge, ad told me to keep the first one too. Stand-up guy.

Well you know that your trailer was the inspiration, I stole several ideas from your build Mine rack only came with two of the straps, but I found some decent velcro ones at Northern Tool that worked for my needs.

The Pioneer Racks look like a great use of space on the back of the trailer, but where do you guys mount the license plate?

EDIT: I see one of you hung it (precariously?) from the bottom of the bumper.

Actually I hung mine on the frame and the bumper protects it real nice (as well as the tail lights).