The following is the reply I received from Amsoil when I sent them the above closeup photo of the unsecured center tube and suggested that the unsecured tube was easy to collapse and that this lead to the failure of the element.
"Jim,
Nice photo, what are you doing changing oil?
The center tube is not the problem, a seal nor reinforcing is required at that juncture, the tube merely supports the media and tends to channel the oil flow through the filter.
The real problem was either the engine or filter by-pass valve or the pump pressure regulating valve. I don’t know what the temperature went down to in your area, but at 40 below any thing can happen and when that occurred the weakest link (and fortunately the least expensive part in this case) gave in.
Jim, I’m sorry that AMSOIL slipped on your scale of expectations; We take pride in makeing an excellent product because we use only the highest quality material under exacting specifications. When used according to our application recommendations our products are designed to meet or exceed OEM performance criteria.
I have attached a link to this communiqué that you may find interesting and informative which deals with filter issues such as you have inquired about.
AMSOIL Technical Services"
The link that he refers to is for the Filter Manufacturers Council. I've never heard of it - has anyone on this Forum??
They blame collapsed center tubes on anything but the filter itself!!!
Here is what they have posted in the link he provided:
Technical Service Bulletin 88-3R
Diagnosing Engine Oil Filters With Collapsed Center Tubes
When a collapsed center tube or element is discovered, the natural tendency is to assume something is wrong with the filter (Fig. 1). This is not the case, but is a symptom of problems with internal engine components.
Most engines incorporate within the oiling system a by-pass valve across the inlet and outlet of the full flow oil filter. The valve is designed to open and by-pass oil around the filter and/or element when the restriction reaches its opening pressure (Fig. 2). The by-pass flow circuit insures oil flow to the engine when there is a significant restriction across the filter due to plugging or cold start conditions. Typically, engine manufacturers design by-pass valves to open at a pressure differential of approximately 10 to 30 psid with some as low as 4 psid (28 kPad), with some opening as high as 75 psid (500 kPad). Some engine manufacturers have the by-pass valve located in the filter mounting base on the engine, while others locate the valve in the filter. Either way, the same purpose is served. Oil filters are designed to withstand, without collapsing, differential pressures significantly greater than those experienced under normal operating conditions. Therefore, when a center tube or element has collapsed, it is usually the result of a "sticking" or otherwise malfunctioning by-pass valve.
In some instances, a "sticky" filter by-pass valve alone is not enough to collapse the center tube or element. The oil pump pressure regulating valve may also stick in the closed position, which results in increased pressure and oil flow through the filter (see TSB-83-1 or PDF). Although this condition may be only momentary, it can quickly collapse the center tube if the by-pass valve fails to or is unable to relieve the excessive differential pressure.
A collapsed center tube or element can lead to a loss of filtration and oil flow to the engine. There is the possibility that interior parts of the filter or filter media may be physically displaced and could migrate into the oiling system interfering with the oil flow.
The malfunction of the filter by-pass and oil pump pressure regulating valves and the subsequent collapse of the center tube or element may not cause noticeable damage. However, at times it can result in a catastrophic failure of the engine caused by seizure of a piston, connecting rod, or main crankshaft bearings among other failure possibilities.
The malfunction of filter by-pass valves and pressure regulating valves has been traced to:
sticky surfaces caused by cold, highly viscous oil;
oil contaminated by excessive condensation, coolant, or oxidation;
neglect-extended oil drain and filter change intervals;
carbon grit that temporarily jams a valve;
sudden acceleration of the engine with any of the above conditions.
Discovery of a filter with a collapsed center tube or element calls for the inspection of the by-pass valve, if not built into the filter, and the oil pump pressure regulating valve, plus a review of the engine's performance and maintenance history.