Missing plate 09 Columbia

id be more worried with the rust

 

I see a lot of trucks missing the clutch cover. I can't say that I've ever seen it cause a problem directly, but I wouldn't want dirt, salt and water getting splashed up there. According to a Spicer clutch class I went to years ago, they say that the clutches are designed to swirl the air and draw clutch dust away from the clutch discs and the slot in it creates a low pressure when driving to pull dust out. With the cover missing, it creates turbulence, that can't happen and clutch life is reduced. I never had the time or motivation to actually compare clutch problems and clutch life to trucks with or missing that cover. But all of our trucks have them and I put them back on when I take them off.

As a side note, if anyone has a chance to attend a Spicer clutch review, it's very interesting. You get a class on how they work, selection, installation and adjustment, the usual short sales pitch, then they bring in a pallet of failed clutches and you rip them all apart to determine the failures.