Pulling M105 Trailer, Modified

[Unimog404]

Hi,
After searching the archives here and elsewhere,
I have a question:

I just bought an M105 trailer with a Unimog radio box mounted on the
back. What kind of tow vehicle do I need to safely pull this thing?

My intended tow vehicle is out for repairs, maybe for a couple
months. I do have a jeep Rubicon unlimitted with a 3500 pound
towing capacity, and since the weight of this thing may be right
around 3500 pounds, I figured I could at least tow it around
empty with the jeep for short distances while awaiting the repair of the other
vehicle.

Then I saw this thread:
http://www.steelsoldiers.com/trailers/46049-towing-m105-behind-jeep-wrangler-10.html

Clearly people thought that the jeep wrangler mentioned, with its
2000 pound towing capacity was inadequate for the task of hauling
a loaded m105.

This trailer had its bed removed (taking it down to about 1500 or 1600
pounds according to estimates I've seen in this forum) and then
a frame added to attach a nearly empty unimog 404 radio box,
which weighs about 1900 pounds according to estimates on
a unimog forum.

this would give the trailer a total weight of about 3500 pounds, which doesn't
sound like much margin. But then, I've never towed a trailer before,
so what do I need to safely tow this beast?
Thanks,
Joe,
Wyoming

 

[Recovry4x4]

If you are not experienced with towing trailers, I would hold off. You would be right at the ragged edge of what the Rubicon is rated to tow but it's certainly not designed to stop that weight without trailer brakes. It will make it go, won't make it woah! If you are going to move it around on your property, I say go for it, get some practice. I move my trailers around with a golf cart all the time. As far as on the street, its a risk. If you are asking not if you should but what you need, you need air and a metering valve of some sorts to operate the trailers brakes. This will get you close to legal. Also, do you have a plan to compensate for the 36" hitch height of the 105?

In closing the question in my mind is could you or should you!

 

[Unimog404]

Recovery,
Thanks, that pretty well covers it.
I was going to buy a pintle hitch that plugs into the Rubicon's receiver and sticks up
much higher. It sounds like with that, I could tow the trailer around the property,
learn how to handle a trailer, and discover what maintenance this newly purchased
trailer might need, all while putting together a better tow vehicle.

The better tow vehicle is a Unimog 404, former swiss troop carrier. I've seen posts
from someone here who has a similar setup. But this unimog has no air to run the trailer brakes, so it sounds like I should add a compressor to the mog, yes? Anything else I'll
need to do to the Unimog?
Thanks,
Joe

 

[AaronW]

I think recovery has it covered. I own civy jeeps and military trailers as well. Even as a jeep lover, I consider it a horrible tow vehicle. Sure, they are great for shuffling trailers around the yard. I would also consider towing a very light, small utility trailer. A 105 behind any stock Wrangler would be inviting disaster in my opinion.

 

[SETOYOTA]

I have to say you have the cart before the horse. There is no vehicle particularly suited to pulling a stock M105 other than heavy duty truck with a frame mounted pintel at the proper height equipped with air couplers.

Using one of those modified hithches is fine to move a empty trailer but thats about it.

 

[91W350]

I have to agree, after towing a M105 behind my M1008, I was surprised how heavy that little chunk of a trailer really is. The M1008 handled it pretty well, but I was still kind of surprised. I pulled trailers 1000s of miles, maybe it is the slop in the hitch design. Glen

 

[jesusgatos]

...I could tow the trailer around the property,
learn how to handle a trailer...

The second part of this is that makes me think you should stick to the first part.

 

[M813rc]

As a Unimog owner and experienced trailer puller, I would not tow that trailer behind the Mog without trailer brakes either. My

There are folks on here who will say "I pull my M105 at 100 mph behind my Mini Cooper....", but I don't want to be on the road when they try to stop!

Cheers

 

[SixSpeed]

The better tow vehicle is a Unimog 404, former swiss troop carrier. I've seen posts
from someone here who has a similar setup. But this unimog has no air to run the trailer brakes, so it sounds like I should add a compressor to the mog, yes? Anything else I'll
need to do to the Unimog?
Thanks,
Joe

Trailer air brakes were available on 404's. My two TLF8's had trailer air brakes, but from what I see the military versions don't USUALLY have it.

An M105 with a loaded Radio box is a heavy beast. A radio box full of "stuff" can weight almost 3000lbs. An M105 trailer weighs around 2600-2700lbs, I'd say with the bed removed, you'd be looking at a minimum of 1800-1900lbs. Add that to a radio box and the trailer probably weighs a minimum of 3700lbs or so, possibly up to 5000lbs loaded with gear.

I once towed a car (3500lbs) on my trailer (2000lbs) with my last Unimog (Stock 404 TLF8 with upgraded igniton) and it was PAINFULLY slow. Stopped it pretty well though, I keep my brakes in tip top shape. Painfully slow as in it took about a half mile to reach its 45mph top speed. A 404 just doesn't have the torque (or horsepower really) to tow anything heavy over the road.

The only thing I would be comfortable towing that trailer with no brakes would be a minimum of a 1-Ton truck.

I think I know the trailer you bought though, a Unimog Radio Box on an M105 is a SWEET setup, its just a bit heavy.

 

[tennmogger]

1900 to 2000 lbs is a good estimate of a Unimog radio box weight. I think you are slightly underestimating the '105 at 1500 lbs... it might be more.

That combination has a high center of gravity, another consideration against towing with a low hitch. Those raised hitches for a 2" receiver put tremendous torque on the total hitch and should be avoided, IMHO. Jeep as a tow vehicle? No way.

The 404 could pull that combination. At probably 6500 lbs for the truck, vs 3500 for the trailer, if speeds were kept slow I'd pull it with no trailer brakes. But, I'd put another 1000 lbs on the back of the 404 truck to control the rear end. My 404 radio truck pulls a loaded M-105 with no problem, but this truck weighs over 8000.

Definition of slow top speed for a Unimog: Don't go any faster going downhill than it will go up hill!

Bob