Continuity: While they are in the canoe, Tom, Jerry and Dan start to spray each other with water and Jerry's clothes change between shots.
Continuity: When Dan, Tom, and Jerry encounter the hard rapids right before they flip over, Dan's hat disappears and reappears between shots.
Continuity: Around the camp fire, Jerry's coat is alternately half open, fully zipped and then half open again.
Crew or equipment visible: Safety diver visible when Jerry is on the surfboard and catches a wave.
Errors in geography: There are several palm trees along the shore of the river which would not exist in the Cascade Mountains of Oregon.
Continuity: When Dan, Tom, and Jerry are found in the barn of the pot-farmers, Tom puts the weed he was trying to steal behind his back three times, then in the next shot the weed is gone.
Continuity: Near the end when Elwood, Dennis, and Sheriff Briggs are about to kill Tom, Jerry, and Dan, Elwood's gun suddenly changes from a rifle to a handgun in a closer shot, and then back to a rifle in a wider shot.
Revealing mistakes: During the struggle for the pistol at the bottom of the mine, the magazine comes out of the pistol (possibly unintentional). You can see there are no bullets in the clip.
Revealing mistakes: When Dan's receptionist enters the room to tell him that he has a phone call from Jerry, the film is reversed. You can tell this because of her name tag and because the phone he picks up in the next shot is the same one that appears next the her on the wall.
Continuity: When the canoe has flipped and the guys are trying to keep together, their shirts are life vests. When they're safe again, the life vests turn back to shirts.
Revealing mistakes: Flower and Butterfly have hairy legs because they are self-purportedly all-natural; however, their armpits are shaved.
Continuity: When climbing on the canoe after the rapids, Dan's hair is messed up. But after falling down the waterfall and finding land, his hair is combed to the side.
Errors made by characters (possibly deliberate errors by the filmmakers): Tom says shining the salmon is an old Cherokee trick, but the Cherokee lived nowhere near were any kind of salmon would go.
Continuity: When the Sheriff, Dennis and Elwood raise their weapons before the hand grenade sequence, Elwood is armed with a 9mm but in the reverse he has an assault rifle.
Crew or equipment visible: In the pot growers' field, when the pot growers have the laser scope pointing at the plant in front of Tom, Dan, and Jerry, someone can be seen crawling on the ground behind the plant.
Continuity: After the funeral, Tom, Jerry and Dan go back to their old tree house. They find their old treasure box and the camera shows a shot of the box with the lock in the hole but clearly unlocked. Then the say that they can not get into the box but Dan tells them the combination and then they say that the combination worked even though it had clearly been unlocked before he tried the combination.
Crew or equipment visible: When Jerry is on Dan's cell phone with Denise, Dan and Tom walk into the scene. They step in too early, walk back out and walk in again.
Continuity: Dan's C3-P0 figure from the 1980s is metallic bronze. That version of the figure wasn't released until the mid -'90s; it should be painted yellow.
Continuity: When the three guys are forced to enter Del's house, it's a rainy night. However, in the next few moments, after Del lights the fire, we can see through the window that it's daylight
Revealing mistakes: After the guys regain safety from the rapids, and unflip the canoe, they appear to be in calm water. Seconds later they are back in rapids again, and fall down a waterfall, there would be no way for the water to be calm right in front of a waterfall.
Miscellaneous: When Tom uses the flashlight to catch a fish, he catches the fish and then throws is at Jerry and Dan, but when they throw it back in the water the fish floats before the scene changes.
Continuity: After the pot farmers are bombed with the poo bags from the treetop and have taken off after the boys on the all-terrain vehicle, the crap they have been bombed with is suddenly missing from their clothing and faces.
Continuity: When Dan gets onto the overturned canoe, he sits right in front of Jerry, so close that Jerry puts his arms around him. In the next shot he's moved a few feet in front of him.
Factual errors: When the guys are in the tree with the girls, they call for help on a CB radio. The bad guy hears and responds to them on an FRS radio. This is impossible since the CB works in the 27 MHz range, and the FRS radio works in the 440 MHz range.
Continuity: When the pot farmers confront the guys at the tree house Tom sets up a zip-line out the back for Jerry and Dan to escape on. When Jerry's preparing to go down he has a piece of cloth to hang onto but when they show him sliding down the line you can see a trolley hooked up to the zip-line.
Continuity: After Tom's arm is sewn up and they are trying to get away, Tom sits out in the rain without a trace of a wound on his left arm.
Revealing mistakes: When Del is shooting at Dennis and Elwood, sparks from the ricochets are seen on the fenders. This isn't possible because the fenders, like most of the ATV's panels, are made of plastic. Also, even if they weren't, bullets are made of lead, which won't cause sparks even against metal objects.
Errors made by characters (possibly deliberate errors by the filmmakers): When Dan, Jerry, and Tom are driving 'the duke' to go on their expedition, Dan refers to 'the Duke' as having "the 318 V8, they're bulletproof." Wagoneers were never offered with a 318in3, especially not in 1977. The 318 was a Chrysler motor, and in 1977 Jeep was still under the ownership of AMC, and would come with either a 258in3I6, a 360in3V8 or a 401in3V8.
Errors made by characters (possibly deliberate errors by the filmmakers): Fish viewed at the outset of the journey are incorrectly identified as brown trout. They are rainbow, identified by the splash of color along their side.