Why NOT tow with a shackle flip?

[tRustyK5]

Rene, what brand/model of wd hitch do you have?

Thanks
Dave

It was a Reese, and rated for 10,000 lbs with the WD set-up. I no longer have the reciever hitch though, and can't recall the model number.

Rene

 

[jac6695]

I wonder how those Dodge SRW 2500's get away with towing? It just has to be scary, I'm sure of it.

 

[BadDog]

Well obviously they have it figured out, otherwise they wouldn't accept the liability. Still, I expect it was primarily done to more easily provide improved ride unloaded, and then they figured out how to deal with the variable rate issue in a different way. I wonder what the rest of the pack looks like.

And it seems that these trucks wouldn't have the "way overload" capacity that previous trucks had. You know; when people put a full long bed load of green wood on a 1/2 ton truck and squash it, but it's still not on the bumps? With a compression shackle, it seems that these trucks (the Dodge in question or flipped GM) would either hit the spring on the shackle if enough arch, or invert the spring if not, or just sit firmly on the bump stop assuming it is positioned low enough and is strong enough. All that because the compression shackle naturally causes a decreasing rate (which could be offset with heavier secondary leafs and/or overloads) where tension causes effective increasing rate.

Repeating what I've said before…

And I still stick by my caution on working a shackle flipped truck at or near full capacity. I think the points made about changes in behavior between compression and tension shackle are simple physical facts and do not seem to be debatable. If you take an "n" rated truck, change it from tension shackle to compression shackle, you have change a major component of the suspension to have very different characteristics than the factory setup on which the tested/engineered rating is based. That does not mean you can't still work it at that level successfully, doesn't mean that at "n-m" load it is going to fail catastrophically, but it DOES mean that you have changed it's behavior at a given weight AND (IMO) it is clear that you have at the very least lost some of the "safety factor" and ability to control the load. I believe these are all clear facts in evidence and I do not believe there can be any controversy over them, so the only point of discussion is "how much" and "does it matter". Those questions are difficult to pin down.

 

[84_Chevy_K10]

And I still stick by my caution on working a shackle flipped truck at or near full capacity. I think the points made about changes in behavior between compression and tension shackle are simple physical facts and do not seem to be debatable. If you take an "n" rated truck, change it from tension shackle to compression shackle, you have change a major component of the suspension to have very different characteristics than the factory setup on which the tested/engineered rating is based. That does not mean you can't still work it at that level successfully, doesn't mean that at "n-m" load it is going to fail catastrophically, but it DOES mean that you have changed it's behavior at a given weight AND (IMO) it is clear that you have at the very least lost some of the "safety factor" and ability to control the load. I believe these are all clear facts in evidence and I do not believe there can be any controversy over them, so the only point of discussion is "how much" and "does it matter". Those questions are difficult to pin down.

How do you seem to have a way with words that I never can have?

Agreed 100%, wish I could have said it that way.

 

[BlueBlazer]

That does not mean you can't still work it at that level successfully, doesn't mean that at "n-m" load it is going to fail catastrophically, but it DOES mean that you have changed it's behavior at a given weight AND (IMO) it is clear that you have at the very least lost some of the "safety factor" and ability to control the load. I believe these are all clear facts in evidence and I do not believe there can be any controversy over them, so the only point of discussion is "how much" and "does it matter". Those questions are difficult to pin down.

I agree 100%.

 

[BlueBlazer]

Not meant to be a slight against you or a personal attack, but that is not at all what you have told me in the past Tim. You said it is outright dangerous to tow with a compression shackle and to do so is foolish where as Russ has said yes, there will be a change, but will the change be a lot or enough to worry about. There is a huge difference in your philosophies IMO. Are we done with this argument now since your yourself will have a tow rig with a compression style shackle. It would be nice to put this one to rest.

 

[BadDog]

Yes, I think we will call this done. For the most part it's all been said at least twice in this thread, and in several other threads we could turn up easily in search. There is nothing left but to argue the same points, and considering the potential in that direction, and the fact that this thread has grown too big for anyone to effectively use, I'm going to close it before things turn nasty again arguing about who said what...

Edit: Obviously, if I'm wrong and there is more to discuss on one of the side issues, you can make a new thread to discuss it further...