Wide load

[hethead]

It‘s a long story, but I’m using the running gear (tandems) from a log trailer with a 35 ton load rating to build a trailer big enough to haul my steel hulled, 40 ft landing craft. Low boy style. Trailer with boat will be about 40k with 15k on the Pintle. Towing with my M820 (box removed) with a slightly tuned up, stock 855. I’m gonna be about 11’ 6” wide and have about 100 miles to cover. Anybody with experience doing heavyish tows on the Pintle, I appreciate your input.

 

[NDT]

Your plan is very confusing. My plan would be to buy a decent drop deck trailer with 40’ deck, and then sell it afterwards if I had no use for it. You want to be as non-sketchy as possible with this since you have to permit the load etc.

 

[hethead]

Your plan is very confusing. My plan would be to buy a decent drop deck trailer with 40’ deck, and then sell it afterwards if I had no use for it. You want to be as non-sketchy as possible with this since you have to permit the load etc.

It is a long story, but I have a use for the tandems, long term. I can’t sit the boat on a flat deck trailer because of the prop, rudders etc. Basically, nothing exists that I can buy to haul the boat and keep it under 14’ tall, so since I already have the tandems, I‘ll build one and the steel will be rolled into my next iteration of the trailer. I’ve built a lot bigger things that passed inspection so it’s something I’m comfortable with. I just haven’t towed more than 3 or 4 tons with this truck. (heavy towing on the pintle experience is what I’m asking for)

 

[HDN]

With the stock motor, the M820's maximum towing capacity is 15000 lbs according to the TM. I can't remember if that's doubled for paved roads like cargo capacity was. The M818 tractor could take a maximum of 37500 lbs on the 5th wheel (again, not sure if that's doubled for paved roads).

By 15k on the pintle, is that a vertical load? I'm sure the data plates assume that the 15000 lb capacity is only partly loaded vertically on the pintle hook with most of the weight being on the trailer's wheels. I haven't looked at a military trailer data plate lately but I'd think there's a tongue weight allowance for the trailers. For example, the tongue load on an empty M1061 trailer is 500 lbs, while the rest of the trailer's weight is on the wheels, which is about 7000 lbs. I know the truck pintle hooks and mounting points are pretty strong, but I'm not sure how strong in either vertical or horizontal loading.

That said, I'd be more concerned about stopping, especially with single-circuit air-hydraulic brakes. I'd consider a road tractor with full air brakes, unless there's a reason you need all wheel drive.

 

[hethead]

With the stock motor, the M820's maximum towing capacity is 15000 lbs according to the TM. I can't remember if that's doubled for paved roads like cargo capacity was. The M818 tractor could take a maximum of 37500 lbs on the 5th wheel (again, not sure if that's doubled for paved roads).

By 15k on the pintle, is that a vertical load? I'm sure the data plates assume that the 15000 lb capacity is only partly loaded vertically on the pintle hook with most of the weight being on the trailer's wheels. I haven't looked at a military trailer data plate lately but I'd think there's a tongue weight allowance for the trailers. For example, the tongue load on an empty M1061 trailer is 500 lbs, while the rest of the trailer's weight is on the wheels, which is about 7000 lbs. I know the truck pintle hooks and mounting points are pretty strong, but I'm not sure how strong in either vertical or horizontal loading.

That said, I'd be more concerned about stopping, especially with single-circuit air-hydraulic brakes. I'd consider a road tractor with full air brakes, unless there's a reason you need all wheel drive.

The pintle tow rating is doubled to 30K for road use. The M818 is 55K "on the 5th wheel", highway. Those aren't vertical hitch loads. I'm pretty confident the 30K rating is fairly conservative, since they spec'd a pintle hitch that's rated to 100,000 lbs. The tandem has 7" wide drum air brakes on both axles. Stopping won't be an issue.

Specifically, I'm hoping someone who has already towed this much on the pintle can share their experience.

 

[sue]

We offer encouragement and hope you press on,
Pintle should be good.

 

[hethead]

We offer encouragement and hope you press on,
Pintle should be good.

Good experience or bad, it's bound to be an adventure and I'll post results!

 

[hethead]

Trailer‘s about done. Wiring needs finished. Air brakes are done. I have a good test drive video but not sure if I can upload that. Maybe YouTube…

 

[Mullaney]

Trailer‘s about done. Wiring needs finished. Air brakes are done. I have a good test drive video but not sure if I can upload that. Maybe YouTube…

.
Yeah... Kinda crummy, but the site doesn't host videos. Gotta go to YouTube or somewhere similar and drop a link in a thread here. Just hope that one day that site doesn't disappear because twenty percent of the content here would go away too.

That is a neat looking trailer!
It sure would be neat to have a picture of the boat this thing is going to haul.

 

[G744]

I once towed a 40' mobilehome (house trailer) some 50 miles on I-10 with my M54A1.

We had an oversize permit and lightbar for the job. Turns out I couldn't get past 30 MPH without the truck 'hopping', due to the heavy load on the pintle.

With the trailer on the truck, it set down more than hauling a bed full of gravel, even.

What appeared to be was the rear rears tires were compressed more than the front rears, even with extra air in them, causing a ratio problem as both axles are locked together via driveshaft.

Got the job done, no other problems or damage to anything. My guts were hurting from all the jostling, tho.

If I ever have to do something like this again, I'll pull the intermediate driveshaft.

DG

 

[SCSG-G4]

Trailer‘s about done. Wiring needs finished. Air brakes are done. I have a good test drive video but not sure if I can upload that. Maybe YouTube…

If you want to talk to someone about a heavy load on a pintle (horizontal, not vertical as in your case) ask Adam (ferroequinologist) about the time he used Bella to pull rail cars off a barge. Not anywhere the distance you are talking about, but the weight pulled is astounding.

 

[hethead]

If you want to talk to someone about a heavy load on a pintle (horizontal, not vertical as in your case) ask Adam (ferroequinologist) about the time he used Bella to pull rail cars off a barge. Not anywhere the distance you are talking about, but the weight pulled is astounding.

That sounds like a great story!

 

[hethead]

I once towed a 40' mobilehome (house trailer) some 50 miles on I-10 with my M54A1.

We had an oversize permit and lightbar for the job. Turns out I couldn't get past 30 MPH without the truck 'hopping', due to the heavy load on the pintle.

With the trailer on the truck, it set down more than hauling a bed full of gravel, even.

What appeared to be was the rear rears tires were compressed more than the front rears, even with extra air in them, causing a ratio problem as both axles are locked together via driveshaft.

Got the job done, no other problems or damage to anything. My guts were hurting from all the jostling, tho.

If I ever have to do something like this again, I'll pull the intermediate driveshaft.

DG

That is not something I had even thought of….

 

[hethead]

.
Yeah... Kinda crummy, but the site doesn't host videos. Gotta go to YouTube or somewhere similar and drop a link in a thread here. Just hope that one day that site doesn't disappear because twenty percent of the content here would go away too.

That is a neat looking trailer!
It sure would be neat to have a picture of the boat this thing is going to haul.

I’ll post one up!

 

[hethead]

This is Thor about 12 years ago. A lot rougher looking now. I’m removing the wheelhouse and lowering the main structure about 2 1/2 ft. It’ll be 12 ft tall at that point. Wooden superstructure, steel hull, Detroit 6-71, Twindisk transmission. 40 ft long x 13 ft wide. I’m cutting the side decks off to make it less than 12 ft wide for the trip.

 

[hethead]

Started loading my landing craft onto that trailer I built. First step is to drag that boat/trailer combo as far as I can up the ramp to keep my "in water" work to a minimum during the final stages of loading and securing. Boat ramp is not designed for 65' trailers so my tandem was 20 ft underwater, hanging out over a drop off / half on top of a sunken wooden boat is was crushing. and the trailer frame rails were sitting on the ramp.

The trailer weighs 5 tons, the boat weighs 20 tons and that 809 dragged it 40 ft on it's keel, digging through concrete.... uphill (while accidentally ripping through a dock beam). The harbor police know my boat and are loving this whole process. I told them about my log splitter incident with the dock beam and all they wanna know about is the truck.

These things can display absolutely brutal strength.

 

[G744]

Yep, 5-tons have the "come with me" deal in the bag.

 

[hethead]

Yep, 5-tons have the "come with me" deal in the bag.

They sure do. I tried to be gentle once the boat was attached to the trailer but if I was heavy handed it would just rear up and snatch that 25 tons up the ramp like it almost wasn't there.

 

[swbradley1]

Nothing a little 14liter Cummins won't do.

 

[hethead]

Nothing a little 14liter Cummins won't do.

Nothing against an 8.3, but this kind of work (and that heavy a crankshaft/flywheel) is exactly why I wanted a full size, long haul "big rig" 855. This is the first time I actually worked it in the neighborhood of it's designed load. It seemed to love it. Puffed just a touch of black smoke when I leaned on it and never ran/idled smoother. I'm running 200 psi on the rail, 10 lbs of boost and set the governor to defuel at 2400. Not that I was anywhere near those numbers pulling this up the ramp. I haven't hit the road yet. Just spent 5 or 6 hours pulling it up in 1-2 ft increments as we laid down ramps to raise the trailer enough to minimize high centering at the crown of the ramp. Still dug a couple channels in the black top with my cargo chains (that wrap the frame rails) but mostly cleared it. It would drag it through the concrete and black top but I was afraid I'd crack a weld on the trailer or something stupid so I tried to be as easy as I could. But I was on this ramp for 8 days and ready to gtfoffit. It was like a mini drydock really, trying to raise a damaged hull without collapsing it.