Never heard of it. Do you have any other information.
I've got the older 3126 and often wondered why the didn't put a fan clutch on the rig. The fan does pull a good bit of horsepower with it's direct drive, so you'd think that by clutching it and not running it fulltime, mileage could be inproved.
Joe & Shelly, Justin, Tyler, Alyssa | Butler PA
2008 Tiffin Allegro Bus 43QRP|Cummins 425|Honda CRV