I have a sandrail that I keep in an enclosed trailer and on a recent trip to the sand with the trailer when the weather was warm, I noticed that I was getting a water temp rise when on a long climb and it would drop back to where it normally runs when the road leveled out. Speed did not seem to matter.
On looking things over I noticed that the bottom half of the radiator was partially plugged with the blowby from the engine vent. This truck only has about 60K on it and I am the second owner and I had never really looked that hard down there before.
I used some citrus degreaser and dissolved the gunk and hosed it out and it solved the heating problem. Just thought I'd pass this along.

 

Now all you have to do is relocate that breather so it does not do it again!!

 

If you drive off road much, you might want to spray it down again and spray radiators from the backside with something like this. It will get a lot of the dust, dirt, grass, etc out of there.

 

here's a word of warning, don't use too much pressure as in a pressure washer, it will bend the fins

 

This little gizmo does not have near as much pressure as a commercial washer. If you happen to have super high water pressure at your house, note that there is a high tech device on the hose for regulating the pressure.

 

Sounds about normal to me. Diesels always generate more heat when it pulls.

 

.....and when you pull your radiator out and really CLEAN IT you'll see it's the only way to fly.





....de-greaser and high pressure, or better yet, a steam cleaner will make it like new.

 

That's gotta be a worse case scenario. I've got 113k on mine and it looks nothing like that and that's after several mudding excursions and what not.

 

I have 140,000 on mine and it doesn't look greasy at all. Just dusty. You been following somebody with engine problems??? :P

 

The pic of J Body's radiator is on the fan side.
I have my bottle removed, and hose extended, but I am also seeing a rise in temps. I will clean it out when I get back.

 

NOT MINE!!! (you could eat off my engine...I'm kind of picky that way)......just one of many I've done at work...and yes, that was a bad high miler. And I believe the "puke" bottle didn't come about until 2000 so you 99 and back guys wouldn't have this issue as bad.

 

Sorry. I remember when you first posted that pic years ago.