Radiator needs exterior cleaning

Cleaning just the radiator from the rear is not likely to bend fins.

But the real problem is that it is very unlikely to properly clean the FRONT of the CAC. And that is where the vast majority of the dirt is deposited.

Said another way, shooting through the radiator, air gap and CAC with enough force to blow the accumulated dirt off the front of the CAC is a very different beast.

Proper cleaning of the CAC really has to be done from the front.

And, best cleaner is Simple Green EXTREME. It is aluminum friendly-- developed for degreasing aluminum airplanes.

Yeah, I love those "bent fin" posts. Use some common sense and you can clean your radiator fins with high pressure sprayers without issue. I do know that the rear radiators are much more difficult to clean due to the gap in the middle between the 2 radiators but flushing from the rear and top center should get you in pretty good shape. If you can add some soap (Dawn) to the flushing process and let it sit you can get more of the grease out of there.

My rear radiator/Cummin's started overheating at 30,000 miles. I bought it used. I spend a lot of money having it removed and cleaned. Since that time, the slobber tube has been extended and routed down below the radiator. I also take advantage of the DIY car washes that have a 14' bay. I just pressure wash it from the rear, insuring that I hold the wand at a 90 degree angle to the fins and slowly move one or two rows at a time until I have covered the entire radiator.
I never have an overheating problem so I'm sure the re-routing of the slobber tube is a big contributor to it, but the pressure washing just makes me feel better about it.
BTW: I know the next post will say that I could bend the fins on the radiator but I have never bent one in 11 years of fulltiming.

Here is a link to a discussion on this. If you can not get it, let me know and I will copy and paste.

http://forum.dieselrvclub.org/index.php/topic,6601.0.html

Have you put an extension on the sober tube? This should stop an further problems after you get it clean again. A friend did his with a steam cleaner and really solved his problems.