difference between 318-360 dip stick?

zakimodo said
I'm pretty sure the length just had to do with what oil pan you have. (Im not sure what those lengths are) When I installed mine I put a little silicone around the base to hold it in place. So far it hasn't leaked.

Correct. Truck (rear sump) and car (center sump) pans used different length dipsticks.

If you have a center sump pan. A stick and corresponding tube from a center sump pan from a 318-340-360 will work.