M51a2 dump truck towing capacity

[2deuce]

I know it is slow, and that doesn't bother me. I'm wondering if it will tow a 20ton tag trailer with a 15 ton load. Considering everything including brakes on it and the trailer are in good shape, will it do that? what is it rated for? I know the M35 is only rated to tow 10K and it can pull more, because I have, but the dash tag says only 10k highway for the Deuce.

Thanks

 

[snowtrac nome]

your trucks load rating is based on its ability to stop a load on an incline and also acceleration speed and of course cooling system capacity with enough gears you can move the world but you will find your impleading traffic or will be un able to stop the load on a long decent. I have herd horror stories of old 5 ton wreckers loosing brakes on long decants. if you do it use caution

 

[doghead]

It does NOT have enough air to use that trailer.

You might get by but be warned.

It also does not have enough power to travel at any kind of road-speed.

If you're just trying to go a few miles once in a while, well maybe...

 

[dmetalmiki]

NOT safely. It has Data plates. Use those to correctly load and tow.
(of course (around your OWN yard or field quite possible))'possible'

 

[armytruck63]

From our own technical manuals section:
http://www.steelsoldiers.com/upload/5Ton/TM9-2320-211-10.pdf

The maximum allowable towed load on the highway is 30,000 lbs for the M51A2 and 15,000 lbs cross country. This assumes working and adequate brakes on the trailer.

Like snowtrac nome says, you will be slow on level ground and REALLY slow going up hills. Make sure you go down a hill in the same gear you used to climbed the hill, if not one lower. That means if you went up the hill at 25 MPH, you should not go down the hill any faster than 25 MPH.

I have pulled 18,000 lbs with my M923, 10,000 lb trailer with a 8,000 lb FWD WWI truck on the trailer plus an M38A1 in the bed of the M923. The trailer had full working air brakes and the M923 provided enough air supply. I was actually able to get up to 53 MPH on level ground, eventually. I only went about 10 miles this way with no big grades. You have to stay on your toes!

 

[doghead]

The air compressor on the multifuels are noted in the -10 to not be used with big trailer due to not enough air.

It's not a problem with the cummins 250 motor'd trucks.

 

[Jbulach]

Just curious, what defines a "big trailer", multiple axles?

 

[armytruck63]

I think what Doghead is referring to is the fact that the M54 series trucks are designed to pull trailers that also have air over hydraulic brakes, just like the truck itself. The air system on these trucks does not supply enough air to safely supply a trailer with full air brakes.

Now you probably could pull a trailer with an air over electric brakes also.

 

[2deuce]

I hadn't thought about the air capability or the air requirements of the trailer. Do all air brakes require the the same amount of air? Three axles would require more air than 2, but do lighter axles use less air? Nothing I would haul weighs more than 30k. Would the M51 handle a 15 ton trailer?I know it would be slow, but I'm now concerned much more with stopping.

 

[armytruck63]

A trailer with air brakes has an actuator or "can" for each wheel or set of wheels. These are basically the same size no matter the capacity of the axle. Two axles would have four cans while a three axle trailer would have six.

Honestly, you'd be better off getting a newer truck to use as your tow vehicle. Either an 800 or 900 series truck would produce enough air for safe towing. Even better would be an M915/M916/M920 with 400 horsepower.

 

[M543A2]

We pull an 18 ton Ferree tandem axle trailer with air brakes behind our deuce and M51A2 dump with no air problems ever noted. We really like the feeling of having the load under control the air brakes on the trailer provide. With the warnings posted here we will watch for it though. I think some of the air supply problem some note with the multifuel compressor could be the result of poorly adjusted trailer brakes. The more air the pancakes require on out of adjustment brakes to travel the distance to apply the brakes bleeds off more of the air supply air unnecessarily.

 

[sandcobra164]

I've towed MK 14 and MK 18 trailers with a Deuce and had no issues with the brakes. A little slow to get moving but honestly, I don't think my trucks brake shoes ever hit the drum when slowing or stopping. I had no issues with the air system staying up to operating pressure on the truck and I checked the effectiveness of the spring brakes by unhooking the "Emergency" gladhand and trying to move the trailer. My old Deuce put up with a lot of non-sense and is probably happy that I no longer own it. It had a later style single piston air compressor if that is of any concern as to cfm of air volume. The older trucks had a dual piston compressor which put out less cfm from what I have read. While it is un-adviseable to pull a trailer heavier than the truck, it can be done as long as the proper safety precautions are followed. Remember, every tractor trailer truck on the road is pulling a trailer heavier than the prime mover. They do inspections and make sure the truck and trailer are ready for transport just as we do or should do. Yes, pre-trip is very important and will be your first step to safe ownership and use of your truck.

 

[Nomadic]

It makes sense to limit the trailer weight to the weight of the truck. On the other hand, there are a gazillion big rig simi tractor truck and trailers out on the road towing much more than the weight of the big rig tractor truck.

 

[162tcat]

It makes sense to limit the trailer weight to the weight of the truck. On the other hand, there are a gazillion big rig simi tractor truck and trailers out on the road towing much more than the weight of the big rig tractor truck.

Pintle vs 5th wheel. That makes all the different in the world.

Sent from my SAMSUNG-SGH-I537 using Tapatalk

 

[Robo McDuff]

I know it is slow, and that doesn't bother me. I'm wondering if it will tow a 20ton tag trailer with a 15 ton load. Considering everything including brakes on it and the trailer are in good shape, will it do that? what is it rated for? I know the M35 is only rated to tow 10K and it can pull more, because I have, but the dash tag says only 10k highway for the Deuce.

Thanks

In short: legally and safely outside your own private land: NO

My M51A2 has been made street-legal for the European Union with both a modern "fish mouth" trailer coupling (pintles are not allowed in Europe) and a fifth wheel (I can switch the dump bed for a fifth wheel and back). I can legally tow a 31 ton trailer or a 31 ton semi BUT my max train weight is 41 ton. So I can tow the max only with a completely empty truck. Now these are theoretical limits exceeding the original M51A2 limits and no way I would try get to the max even on the flat Dutch roads.

Problem is, that neither the engine nor the brakes are suitable to do this. The engine is just your problem, it will be very slow but probably will get you there as long as there are no steep hills to go up or down.

That brings us to the second problem especially going downhill: your brakes. The M51A2 has a 60-year old system of single circuit air assisted hydraulics. Take a trailer and you double your risk of failure along the system, even with an "in good condition" system. Enough members here can testify that a good systems and even recently restored-redone systems can have a failure, either a slow leak or catastrophic hose or seal break.

Trying to handle a too-heavy trailer (for this truck) puts a lot of stress on your system.

Without air you still can brake but difficult. I would not want to try brake an M51 weighing 10 tons empty pulling a trailer of 35 tons with not enough air. In that case, hopefully the trailer is full-air so it will maybe stop the combination because you will not be doing it, at least not in time in an emergency situation.

With a brake oil problem, the situation and your truck will rapidly go downhill.

So yes, these trucks are somewhat underrated but not that much. Probably your truck could do it once or twice but with difficulties and risks. On a regular basis or any serious activity, forget it, get a more modern truck that is build for doing that.

 

[Robo McDuff]

I think what Doghead is referring to is the fact that the M54 series trucks are designed to pull trailers that also have air over hydraulic brakes, just like the truck itself. The air system on these trucks does not supply enough air to safely supply a trailer with full air brakes.

Now you probably could pull a trailer with an air over electric brakes also.

Thanks, this is very important information, I did not know you could not /should not tow full-air trailers with a multi-fuel. Does this go also for the M52A2 or does the tractor version has more air?

I checked the ...10 manual but could not find that reference.

 

[Lukes_deuce]

We pull an 18 ton Ferree tandem axle trailer with air brakes behind our deuce and M51A2 dump with no air problems ever noted. We really like the feeling of having the load under control the air brakes on the trailer provide. With the warnings posted here we will watch for it though. I think some of the air supply problem some note with the multifuel compressor could be the result of poorly adjusted trailer brakes. The more air the pancakes require on out of adjustment brakes to travel the distance to apply the brakes bleeds off more of the air supply air unnecessarily.

How does the M51 tow the loaded Ferree trailer? Do you know how much you gross? Im looking to rent a backhoe and bring it home, locally, for a weekend.