2012 Cascadia

[Rawze]

(03-12-2021 )boyzmom Wrote:  ....
Mechanics said nothing can be done. It's all because of these new dang trucks.
...
We have used this mechanic for years
...

according to your posts so far...
YOUR MECHANIC IS AN OUT-DATED IDIOT!!!! -- THAT IS WHAT THIS ALL DIRECTLY POINTS TO!

KEEP TAKING IT TO PEOPLE WHO ARE SEVERELY UNDER-TRAINED ON NEWER DIESEL ENGINES AND VEHICLES AND YOU WILL GET STUPID RESULTS AND AN EMPTY WALLET!

====

LEARN TO WORK ON THAT GODDAMN TRUCKS YOURSELF --- ESPECIALLY FOR STUPID S$IT LIKE YOUR ASKING ABOUT --- OR GO OUT OF BUSINESS!.

OWNING TRUCKS == LEARNING NOW TO MAINTAIN THEM YOURSELF .. AND NOT GIVING ALL YOUR MONEY AWAY TO YOUR SO CALLED "TRUSTED IDIOT!"

=====

IF THE ECM IS REQUESTING THE FAN TO BE ON PERPETUALLY. ..
Get a copy of Insite and an adapter... LOOK IN THE ECM AND SEE WHY THE ENGINE FAN IS ON!... HOW MUCH YOU WANT TO BET IT IS TELLING YOU THE A/C SYSTEM IS LIKELY REQUESTING THE FAN!.... AND THAT YOUR MECHANIC IS BLINDLY THROWING PARTS AT IT CUZ HE IS NOT SMART ENOUGH TO FIND OUT WHAT IS REQUESTING THE FAN TO BE ON ALL THE TIME!.
Otherwise ... Is the Air-line feeding the fan clutch "ON"/Pressurized at any point to actually shut off the fan clutch?
-- It is not rocket science. - How long you think it would take me to figure out what was wrong?. It is not that complex!. YOUR MECHANIC is the problem!.

=====

Your complaining about a "rattle" --- ASKING THIS ON THE INTER-WEBS IS LIKE THROWING DARTS AT THE MOON!. For all anyone can guess, it could be something serious or it could be the damn clutch-forks rattling around when not under load, and it be completely harmless!-- it is anyone's guess, as no one on here has trucker-E.S.P.