The Contraption - a M101A3 Build

[KellyM]

Inspired by all of the great builds here, I recently picked up a M101A3 from another ExPo member and have started the process of making it mine. As you can see the POs already started to change it into an Expo trailer, which saved me a bunch of work. They were great people to deal with as well.

When my daughter saw the pictures, her comment was "Well, that's quite the contraption!" The name stuck.

Here are a few pictures of it when we got it.



We were literally "mall crawling.



The first step was to cut off the heavy plate steel cover. While it was very stout and secure, and in some ways I hated to see it go, it was difficult to use without strut assist, was very heavy (close to 500lbs) and did not fit with my intended combo camping/utility uses.



I also ordered wheels and tires to match my JKUR.





With the two wheels and tires mounted up, and the expert assistance and guidance from a fellow ExPo'er and M101A1 trailer builder, we pulled the existing axle to get exact measurements for a new axle. The existing axle was wider than I wanted and because it is a 5200 lb axle comes with 6 lugs that would not work with my JK wheels. It also is a 4" drop axle, which either left the axle too low for my purposes, or made the trailer too high with the 35" tires.





The new axle and wheel spacers should be here in a couple of weeks. I'm looking forward to getting the axle installed and the trailer on the road for a shakedown.

Here are a few more pics:



It is a big RTT.



And the bed cleaned out. It had a water tank that I took out. I intend to mount a new tank under the axle.

 

[Martyinco]

Great starting point

 

[SoDakSooner]

Looks good. I have the same harbor freight jack for a nose jack. Not welded on yet.

My CVT was originally on top of my jeep. Couldn't make the jump to the Denali, too big for that, so have a Rainier extended. Looks like yours will fit the trailer perfectly.

Are you throwing the AEV wheels on it, or is that pic just for reference?

I'll be following for sure.

 

[VicMackey]

Looks like you are off and running as they say.

I have an M101A3 and the exact same tent and awning combo that you have. I got lucky as my trailer came with an ARE truck cap on it that has locking doors.

I am looking forward to seeing what else you do to yours.

 

[KellyM]

Looks good. I have the same harbor freight jack for a nose jack. Not welded on yet.

My CVT was originally on top of my jeep. Couldn't make the jump to the Denali, too big for that, so have a Rainier extended. Looks like yours will fit the trailer perfectly.

Are you throwing the AEV wheels on it, or is that pic just for reference?

I'll be following for sure.

Yes, those AEV wheels and the 315/7017 BFG AT KO2 tires will be on the trailer after I install the new axle. They are the same wheels I am running on my Jeep. AEV discontinued the Silver Savegre wheels recently, but I lucked out as Northridge had exactly two left.

I'm not sure about the Denali extended. It is so big. It will typically only be my wife, me and our two relatively small Aussie dogs. The Rainer may be a better size, but we now have this one so we will give it a try. When we are not looking to set up a base camp or have the dogs with us, this is our usual setup:

 

[KellyM]

Looks like you are off and running as they say.

I have an M101A3 and the exact same tent and awning combo that you have. I got lucky as my trailer came with an ARE truck cap on it that has locking doors.

I am looking forward to seeing what else you do to yours.

I like truck caps on these trailers.

Our plans at this point include the axle swap, and figuring out a way to connect the parking brake to the two OE handles. Then once the trailer is at the height I want it, I'll look to shorten the tongue while still allowing a full swing of the tailgate since our kitchen is in the back of the Jeep. At that point, we will do a couple of shakedown trips to see what we think of the RTT. If we keep it, a telescoping rack with actuators will be at the top of the list along with a power system, most likely in a tongue box. We also intend to add a receiver off the back to utilize a bike rack, a water tank (plumbed with the electric pump that came with the trailer), a water heater (undecided about permanently mounted versus one of the freestanding units), paint to match the Jeep and some sort of cover. I will probably start with a fitted tarp, and after that perhaps some sort of tonneau cover that I can easily remove when I need to haul tall things.

Thanks for the interest all. I have pulled ideas from your threads and posts, and will look to share what I learn in this process.

This trailer stuff is addicting!

 

[dstock]

Sub'd!! Love the name, it's perfect!

What's the ETA on the axle?

 

[Ovrlnd Rd]

Glad to be following your thread. I started on my M116A2 generator trailer yesterday and was on the way to the sandblaster when I tripped and broke my kneecap. Going to be 8-12 weeks before I can get any work done on it.

 

[KellyM]

What's the ETA on the axle?

It should be here around the middle of the month. It took a couple of extra days after we measured to finalize an order. The distance between the spring perches and the hub faces was calling into question the weight rating of the axle. Apparently anything over a 23" difference can lower the rating on the standard Dexter axle, even with the 3" tubing. I found a place that could order 1/4" thick 3" diameter tubing which results in a greater than 3500 lb rating (but they still label it as 3500). I'll let you know when it shows up.

I got the 7 pin connector and P3 brake controller installed and took the trailer for a spin today. It tows well with the Jeep, and even without the brakes the stopping wan't too bad. I am currently hunting down a short in the electric brake wiring.

 

[KellyM]

Glad to be following your thread. I started on my M116A2 generator trailer yesterday and was on the way to the sandblaster when I tripped and broke my kneecap. Going to be 8-12 weeks before I can get any work done on it.

Yikes! I hope you heal quickly. I guess you'll just have to do more research and accumulate parts while you recuperate!

 

[Ovrlnd Rd]

Yikes! I hope you heal quickly. I guess you'll just have to do more research and accumulate parts while you recuperate!

Thanks! I have spent the last 2 days doing nothing but net surfing. I found this post which is what I want to do: https://www.4xoverlandadventures.com/anatomy-of-a-diy-trailer-part-3/

He has a thread on here (listed in the write up) but working off my iPhone it was easier to link to his site.

 

[Happykamper]

Ok that thread was motivating !!! Get well soon !

 

[KellyM]

I sorted out the "output short" reading I was getting on the P3 controller after I rewired the trailer brakes (I had cut the trailer brake wires when we took the axle off last week). It was caused by the plug not being completed locked in place. All fixed now. Here is a shot of it hooked up to the Jeep with the existing axle and FJ wheels and tires. The trailer should be about 5" higher after I put on the new axle and wheels and tires to match my Jeep. BTW, the rig is parked slightly up hill in the shot. The rear of he Jeep sits more level than it appears in this picture.



I also took care of the rust on the extended tongue with a wire wheel, and primed it to avoid further oxidation. Do most of you paint or Line-x the tongue and exposed frame?

Then it was time to start figuring out how to bring more toys with us now that we have a trailer.



We are hoping to have room to bring kayaks and SUPs with us on some of our trips, so I test fitted our double Ocean Kayak, which is the biggest one we have. With it on the bed rails, I could still lower the rack at least 10". Without the kayak, I can lower the rack 16". Has anyone created two supported stopping points in their telescoping rack? I am thinking holes that are 10" and 16" down from full extension with hitch pins to hold the rack in place during transit at either of those heights. Thoughts?

 

[KellyM]

Thanks! I have spent the last 2 days doing nothing but net surfing. I found this post which is what I want to do: https://www.4xoverlandadventures.com/anatomy-of-a-diy-trailer-part-3/

He has a thread on here (listed in the write up) but working off my iPhone it was easier to link to his site.

Thanks for the link, M1078. I had not seen that one. What a great build. Since my power system is on the front burner now, I liked seeing his simple and clean power system install.

 

[VicMackey]

Was the 7 pin wiring harness on the JK a plug and play type? If so, what did you go with?