Torque Spec for Plastic Coolant Reservoir Mounting Bolts?

This is on a 2014 Freightliner Cascadia DD15. Reservoir is made out of plastic. Two bolts are 1/2 inch and bolt onto the top of the radiator. Another two bolts are bigger at 5/8 inch and 15 mm and bolt onto a frame.

 

Hahaha. Yeah, that is as forward as I can legally have them on a fully loaded trailer. I do it for the MPGs, that is, reducing the gap between the truck and trailer.

 

I misread your post. I’ve also noticed that my truck has a wider gap than other Freightliners. Maybe it’s because its a 2014 Cascadia, or maybe that’s how the previous fleet specs their trucks. My truck does have smaller truck cab “fins” (?), those things that attach to the side of the truck cab to help close the gap between the truck and trailer. Mine are like 6 inches shorter. I wish I had the longer ones, but I’m afraid they’ll be very pricey even the used ones. On top of that I’d probably have to paint them black like my truck.

 

I measured the bigger bolts (5/8 inch and 15 mm) and both are about 9.1 mm in tread thickness. I went back to the torque spec on my truck airbags based on tread thickness and converted it to my bolt thickness, and it shows 15-25 lb•ft.