Wierd electrical issue

I am having a wiring proplem and am hoping I am not the first
2001 freightliner classic with a det s60
Temp gouge goes off a random intervals also turns on the oil and temp warning lights and at the same time it started with the abs light for the tractor staying on and the abs light is somehow tied in with the fan splendid abs light on fan behaves normal abs light goes out fan comes on
I am being driven nuts with this
Things tried so far temp senders replaced no change
Vigil bar replaced no change cm replaced no change
After all this was out hauling oil down a rough washboard road and every problem except the abs light being on constantly went away for 6 months now it is back to being haunted