Tow Strap size ???

If all your going to do is pull start a bobtail or occasionally pull one off a slick spot then a simple tow strap will do, without hooks so you can get it though your pull point, then a couple of clevis hooks and your good to go. You might consider pulling from the front of your truck as there is not always a place to attach something to the rear, and unless you have a very stout cross member it will get bent up.

 

the reason is for having the right tools for the job, the wrong equipment can easily kill someone.

btw i have broken a 3" 20k lb rated strap pulling a pickup with another pickup. the reason i push the proper equipment so much is because i have seen things happen that only by sheer luck no one was killed.

 

If you are pulling on a bobtail that weighs 20K what is the drag efficient when the other driver lets out the clutch and tries to start the truck? A lot more than 30K I am betting.

 

For pulling a bobtail a 30k strap would be fine in my opinion.

I carry a huge chain....i know it is dangerous but i pull started an 80k rig off the fuel island with it in Georgia the other day.

 

He wants the strap for pull-starting other trucks. Not for towing them around.

 

Pull starts are a lot more complicated than just hook something to the truck and pull.

I have a bit of experience in them...

First of all, most of the drivers today have no idea how to do one.
Second you can not pull start a truck with an automatic.
Third, I find that most of the time, there is not enough air to release the brakes of the truck.

And not to forget that if you are pull starting a bobtail truck, that is great, but it generally is under a trailer and you have to get the fifth wheel released and that sometimes takes pushing back a bit to get pressure off the lock.

Yes the tractor may weigh in about 19000 pounds, but rolling resistance to get it moving is a bit more, and the shock load of them dumping the clutch has to be figured in.

The straps are good ideas when rated about 40 to 50 k in strength.

Now as to hooking to the trucks, yeah you have issues there. Where on your truck are you going to hook to??
And the front mounted or put in tow hooks on trucks are all different... You have 2 different ones for Internationals, 3 for Kenworths, and some Petes. Freightliner has 2 different styles, and then you have Volvos...

Now as to pulling someone who is "lightly struck"...

You have to figure in "rolling resistance" and "gradient resistance" to get it moving or out of the hole. If it has a bit of damage, then you have to also include "damage resistance"

Some of these issues can take that 20,000 bobtail and make it to where you need 40,000 or more pounds of force to get it to start moving. And I will not go into the fact that a lot of times for lightly stuck in sand, snow or mud you need a bit of lift to overcome the suction which is holding it in place.


Have I answered the questions for just basic kind of strap that you would need, if you want to be generous and help others out?

Sorry to be a spoil sport, but I did not mention the potential liability of helping others and the chances of doing damage.

For example if you were to hook a chain around one of the "hendrickson air ride axles" (big box tube front axle) you have the great potential of "kinking" the tube and reducing its strength.

http://www.hendrickson-intl.com/CMSPages/GetFile.aspx?guid=cfdcc825-d92e-45d2-b1e6-c4377f434174

Hope this link is ok to post as it is a service bulletin from Hendrickson in regards to winching, pulling and towing for their axles, which are found not just on Volvos anymore but on Freightliners and Western Stars.


I really hate to say it, but driving a tow truck (yes I have 3 years OTR also) for over 33 years, just shows me that there are a lot of people who think that towing is so simple and easy. Its not and we have a huge amount of information to keep track of so that we know the proper way to do our jobs.

 

i beleive he was talking about pulling stuck trucks. not pulling them around or jump starting them.

and i HAVE done damage pulling a stuck truck. i was in an end dump that has a pintle hook for a dump trailer. the dump truck i pulled had hooks through the front bumper. my truck had to be towed back to yard becuase i shattered the rear end.

for those that think damage can't be done.

pullig a truck stuck on ice might be easy. but a truck stuck in the mud. is gonna take some serious force. depending on how soft the mud and how far he sank.

both dump trucks were loaded and weighed about 50,ooo pounds each.