(Click for video linked to a searchable transcript of this Mad Money segment)
Even the most confident bulls were somewhat shaken by the latest results from UPS.
"I can't tell you how many people I know were using United Parcel as the giant chit in the recovery play," Cramer said.
And now they regret it.
On Friday, UPS pre-released a forecast for profits that came in below Wall Street expectations and shares immediately slipped approximately 6%. The company blamed the weak earnings forecast on a slowing US industrial economy and preference for shipping alternatives that are cheaper, even if they take longer.
"What can I say? How wrong could investors and traders be? A preannouncement of all things. A darned preannounced shortfall And a bad one," Cramer said.
The Mad Money host thinks the forecast can not be ignored. Because UPS ships for both individuals and companies, the results should be considered a signal.
"To me it says that everything you have heard about a strengthening economy must be put on hold," Cramer said.
Going forward, Cramer advocates looking for additional signals that may either confirm or deny the weakness suggested by UPS.