Flat towing M923

[JingoJohn]

NEED OPINIONS AND RECOMMENDATIONS on similar topic (Not attempting to hijack thread) I pulled an XM1073 trailer (7.5 ton) from WVa with a 12,000 crawler on board with my first 923A2 to Denver, Colorado.
NOW, I want to hook my 925A2 to the front of my 923A2 (with a mill spec bar) so I can pull the XM1073 and crawler up a mountain road. The pull would be about 8 miles with a few short grades in the 15-25% (OOPS! EDIT:...% SHOULD BE degrees....BIG difference!) range. The 'road' is not a 'jeep trail' but it is not even up to county secondary standards. I don't want to 'walk' the dozer 8 miles.
IDEAS?
THINKING ON SUBJECT?
RISKS?
POTENTIAL DAMAGE TO either 6x6? (Most important factor)

 

[RustyM923]

NEED OPINIONS AND RECOMMENDATIONS on similar topic (Not attempting to hijack thread) I pulled an XM1073 trailer (7.5 ton) from WVa with a 12,000 crawler on board with my first 923A2 to Denver, Colorado.
NOW, I want to hook my 925A2 to the front of my 923A2 (with a mill spec bar) so I can pull the XM1073 and crawler up a mountain road. The pull would be about 8 miles with a few short grades in the 15-25% range. The 'road' is not a 'jeep trail' but it is not even up to county secondary standards. I don't want to 'walk' the dozer 8 miles.
IDEAS?
THINKING ON SUBJECT?
RISKS?
POTENTIAL DAMAGE TO either 6x6? (Most important factor)

I'd just do it. As long as both trucks are sharing the (properly secured) load, it shouldn't be a problem. watch the Trans and engine temps...

Take pictures.

 

[gerrykan]

I want to hook my 925A2 to the front of my 923A2 (with a mill spec bar) so I can pull the XM1073 and crawler up a mountain road.

Have someone video it for us, and put it on Youtube if possible.

 

[smittyjr355]

"...Being an engineer...and over building...." I doubt it! Have you ever hefted one of those mil-spec tow bars? I doubt you could buy the steel that goes into those WAY OVER-BUILT sufficient for 'combat emergencies' monster bars. Buy one or take up the previous offer for the loaner.

It seems your comment is not aimed to help out with this topic but more along the lines to pick my thread and me apart! Just a question for you. Who do you think designed these mil-spec tow bars for "combat emergencies"??? An engineer that's who! You dont know me or my fabrication abilities so keep your doubts to your self!!!! Thanks

 

[JingoJohn]

Huh? Some paranoid guy thinks he has a corner on opinions. AND wants the rest of us to shut up.

MOST of the engineers I know build things RIGHT; neither over-built, nor under-built with efficient use of materials and money in consideration of production runs. Laymen usually over-build "just to be safe" for the one or two items they build and disregard the excess cost which would make the product not economically viable in large production runs.

BTW, my comment was/is meant to help. Probably a team of REAL ENGINEERS developed the EXISTING mil-spec tow bars then did what REAL ENGINEERS do; tested, tested, tested, tested, tested until they perfected the existing bar.

To make my helpful comment understandable: 'Ya can't do better than the existing bars.

 

[JingoJohn]

Rusty & Gerry thank you for your encouragement. I thought I read somewhere in the TM's to NOT do exactly what I am contemplating. My foggy recollection is that it had something to with the inability to match engine RPM's for both (or several trucks hooked together) which would cause the transmissions to "fight".

Subsequently, I have returned to the TM's several times attempting to find the reference again, to no avail.

On the surface, it sounds like a good idea to climb otherwise un-climbable grades or to cross otherwise un-crossable water or mud obstacles. The idea sounds exactly like something a "Grunt" would come up with to stay dry or to keep a truck from getting stuck in the mud or to prevent un-loading then re-loading a truck to climb a grade. (NOTE: "Grunt" is capitalized and used with great RESPECT.)

 

[smittyjr355]

Thanks for the entertainment!

 

[Tow4]

As far as two trucks pulling a heavy load; heavy haul trucks regularly use a pusher to get a heavy load up a grade or to have enough power and traction to move the load.

As long as the transmissions are in a gear that gives similar rpms in each truck, the HP would be similar and there shouldn't be a problem. The drivers can communicate to keep the power pretty equal between trucks.

 

[dilligaf13]

http://www.youtube.com/watch?v=BbSzYd_dCg4

The one video show a 6 truck push/pull combo. Pretty impressive...

 

[JingoJohn]

Tow, thank you for the scoop on moving heavy loads. I am a bit upset with you though......NOW I want a BIGGER truck like the ore hauler hahhahaha

At first I thought these trucks were 'indestructible'; THEN I read the TM's which say 'don't back up in low range' and I discovered that they are "mortal" and have their frailties. Thank you again.JJ

 

[JingoJohn]

Ooops. "up set" with the wrong guy hhaha WOW! what a cool video! Thank you dilligaf
Thank you, JJ

 

[rhurey]

Well, there's what everyone calls "over building" and building to spec.

Problem in understanding is spec usually has some extra in it, unless you're building disposable crap for use in Harbor Fright.

Example: I'm standing in the boom of an tower ladder up ~120 feet flowing water out of the monitor with 3 other guys. One is from the factory telling us how the boom is rated for 500 lbs when flowing water and how great it is. Together the 4 of us with stuff on probably weigh ~900 lbs. I mention this. "It's designed for a 3x safety factor"

You can argue the tower is either "over built" as it's rate for 500 lbs in that scenario, but can likely hold 1500 lbs w/o failing. Or it's designed to spec, because the spec and published customer use numbers are different.

I suspect with a non-trivial amount of military gear the published "use it for this" rating, and the ultimate design load are not the same, nor all that close.

 

[JingoJohn]

rhurey, I figure ANYTHING "Military" is good for at least 2x stated rating. The rating is designed for the worst possible COMBAT EMERGENCY conditions. As an example: our beloved 5 tons; the TM's clearly state they will carry much more (Somebody probably knows EXACTLY how much more under varying conditions.) and that they are built to carry the stated load (5tons) over the roughest terrain the trucks can possibly traverse.

Another example: I bought seven SNATCH BLOCKS rated at 20,000 Lbs. (each) and they weigh approx. 60 Lbs each. I suspect the ultimate failure number is probably somewhere north of 90,000-100,000 pounds. I base this wild guess on the snatch blocks you can examine at any 4x4 shop. The best brands and highest loads stated are 12,000 to 16,000 Lbs and they weigh about 2-3 pounds.

I sure as H don't' want to sleep under a 100,000 load suspended on one of these blocks! But, it would not surprise me if the ultimate strength is in that range.

ANYBODY want to buy one of the SNATCH BLOCKS? ($180 + S&H)
NSN-3940001059933
P/N-11631726
SHEAVE OD: 8 inches nominal
Max rope diameter: .75 Inch (3/4)

 

[smittyjr355]

you might want to reread the rules because you can't post stuff for sale outside of the classifieds! Just friendly reminder!!!!

 

[Csm Davis]

Okay so you want to get on here and dig up a 2 year old thread and jump on somebody for something he didn't do and then hijacked his thread and try and sell stuff without using the classified adds? Who are you Newby ? This man was smart enough to get a military tow bar and listen politely when we asked him not to build one. Not sure how many military trucks you have moved, I personally have lost count but around 2000 is how many I have moved off Camp Shelby, so lay off the guy.