1.5" OLED display (SPI)... U8g2lib... Mega

I got everything working on the bench... perfectly.
Then I installed it in my Street rod. Got unpredictable and goofy displays.
The only difference is the length of the signal wires between the Mega and the OLED.
On the bench? A few inches(using the supplied pigtail). In the car? About 4 feet, using typical 22AWG wire.
If, in the car I swap out the 'long run' for the 'short run'... all is well.
I have been reading about "distance limitations" but don't really know how to apply most of what I have read. Since everything works great on the bench(short run) I saw no reason to post my code (but I can).
I guess I have 2 questions at this point:

  1. Should I use some other kind of wire for the 4' run?
  2. Are there options within U8g2lib that I could change to address this problem?

SPI ?

I thought most are I2C.

The "Waveshare" 1.5" OLED is configured for both but defaults to SPI.