As I pull the 5th wheel rv, I alway keep an eye on the egt to keep it below 1200. Today, pulling from wy to co, I was running 1100 up a long uphill grade and looked down and noticed the water temp which normally runs a notch below 210 was halfway between 210 and 260 or 235 degees. I backed of the throttle and it returned to 210 but everytime I pushed it for an extended period of time, the water temp went back up. When it went up, I backed off and it came back down.


Relevant data: 2002 3500 d/a, ambient temperature in low 90's, medium to large sized 5th wheel, a/c on, 75mph, 4% grade, no noticeable headwind, all fluids (oil, antifreeze) normal.


So I'm thinking thermostat, fan clutch, etc.


Called chevy dealer service dept and they were going to have me bring it in but then checked with the shop foreman who said running at 235 is ok while pulling a heavy load uphill, a/c on, and temps in the 90's. Basically, no problem even for extended periods of time.


So is that valid, or should the water temp stick at 210 no matter what?

It's a motor working .... http://www.dieselplace.com/forum/smileys/Approve.gif


I wouldn't sweat it ....





Mac

I think my 10K Wildcat is a middleweight. I do not run 75 up 4% grades. The EGT, on level 2, would be in the red in 5th gear and I don't like running 75 in 4th unless just passing. My EGT goes in the red before the water temp even moves off 200. Later! Frank Edited by: Frank Blum

I just got back from a trip in Utah. I have a 3500 Dually. I had my 1121 Lance Camper on towing my 18ft Four Winns boat. The camper weighs around 4200 lbs loaded and the boat and trailer weighs about 3300lbs with everything in it. I was pulling the long grade out of Vegas before Baker, Ca. and I noticed my water temp was at 235. I have no idea what the the grade % is on that particular hill but I can tell you it is a long and steep one. I backed off a little and it cooled right off. That was the only time it got past 210 on the whole trip. Believe me I never turned off my air and most of the time I was cruising 70 to 75. We pulled a lot of hills on the trip but I believe it was the longest and steepest........Gruber

Like the man said, It's a hard working motor... Start worryinghttp://www.dieselplace.com/forum/smileys/Unhappy.gif when it won't cool off when you back the throttle off. Modern cooling systems and coolants are meant to run hotter, due to tighter engine tolerances etc.