I recently flushed and drained the cooling system at 59K. I noticed after a couple of days the temp. gauge was not where it was before I did the flush. I replaced with a new stat when I did the flush so I checked the part # and it was correct. Before it ran(the needle) on the left of the middle mark, after it ran on the middle mark or just to the right. I bled the system again and nothing changed. The other day it some light stop and go traffic I noticed it was to the right and climbing slowly. The fan kicked on and when I was sitting it would hold but when I moved it would gradually increase. I stopped and shut it off and let it cool completely before it got overheated. I replaced the stat this weekend and re flushed the system and filled with new coolant. Now it wants to come up to temp and hold on the left, until I drive(30-40mph) then it slowly moves to the middle mark and then to the right of the middle mark. When I stop it starts to lower without the fan on and usually goes back to the left of center, sometimes it stays at the middle. Then when I resume city driving(30-40 with a few stop signs) it slowly creeps back to center and just to the right. The heater produces heat (allot of heat) but is there air still trapped in the system or is this a possible clogged radiator?

 

Just took it on a 5-6 mile drive. Started cold, in town 30-40 mph with a few stop lights, warmed to normal temp and held through the first couple of lights. Leaving the third it started to raise slowly to the middle. When I got onto the highway it was a tick right of middle. Got up to highway speed and it raised slowly to the right of center a 1/8-1/4" and stayed for 4 miles. got off the highway and it raised a little and then went back down to right of center. I ran it at idle at home and it never went higher or lower. I noticed the fan was not on high when it was idling.

Coolant flow issue?

Fan clutch?

 

That happened to me,but my water pump was goin out.
It could be your clutch goin out also but if it is mine as well go with an efan.
My temp would gradually increase so I just replaced the water pump and radiator
and about two to three months later installed a flexalite efan and it runs great.
My radiator was fine but it had 90000 miles on it so I went ahead and replaced it.

 

Haven't seen any thing coming out of the water pump yet so i'm leaning towards radiator or fan clutch. Probably both while i'm there. It is somewhat hard to understand at 59k the radiator is clogged, but after reading the 4000 threads about the 4.7's clogging issues on here it seems to be the logical choice. The only thing bugging me is the needle moves up on the highway and down idling, shouldn't be the other way around.

 

You might want to check the coolant temp sending unit. It sends the signal to the gauge. If its acting up it could be sending a false signal. Plus there pretty cheap. Just a thought.

 

Well, all seems to be right in Whoville. Replaced the radiator today. Replaced the fan clutch while I was there although I doubt it was bad. Drained the heads so I had a fresh start with the coolant. Seems to be cooling correctly now and the gauge is back to where it should be. After further inspection I should have noticed that I was not getting the correct amount of coolant in during my last attempts at draining an flushing. That thing must have been really CLOGGED. Thanks for the help tafet and dcrow. The sending unit was my next try if the new radiator didn't fix the problem.

Anyone know why the 4.7's radiators clog so bad? Is it the radiator design, type of factory coolant. Mine was factory one and had probably never been drained and flushed, but the owners manual doesn't call for it to be drained until 60 months.

What would be a good drain/flush schedule to keep the new one from getting so clogged?

What is the best flushing fluid/chemical to use?

 

I used a 50 50 mix prestone with water wetter and it works great!!!
Installing the efan was just icing on the cake....glad we could help you.
My next mod will either be an ASP underdrive or headers but I think I am leaning more towards the underdrive.

 

I literaly just went through the same problem. I was getting my truck ready to take the boat out & decided to change all my fluids. This was the second fiush I have done since I bought my 04. I flushed it right after I bought it just in case and used OEM Mopar coolant, it has 106k on it now.

I opened up a can of worms on this one, snapped the top t-stat housing bolt almost flush . Anyway after i finished the flush and I was putting the t-stat back in I was surprised to find debris of something I can only describe as a slightly opaque/white silicate that is typically found in the older PG coolants.

After it was all back together it seamed she was running warmer than usual (midline to a bit above), especially when under load. I drained everything twice trying different filling/burping techniques, even throwing in a new t-stat. I began to actually think I was a bit paranoid about how warm it was running.

Long story short, after running a few tests it turned out to be the fan clutch, I swapped it out and it is definitely running cooler. I will also be replacing my radiator as I think I may have a bit of a restriction from some more of that gunk.

I also switched to prestone yellow coolant (cheaper) and I will do more frequent flushes. IMHO the MOPAR HOAT coolant is not worth the extra cost (coolant & parts) if it leaves that crap behind, it is definitely better than the old fashioned green but the yellow works just as well. O'Riely just started carrying this multi mfg approved HOAT 5/150k coolant I may try next time but I will deffintly be changing and flushing more frequently.

After the radiator I'll work on the efan mod.

Any suggestions on an after market radiator that works with the degas bottle?

As an aside always bypass your heater core and flush separately (forwards & rev) so you make sure you don't blow any of the gunk from the rest of your system into it, one less problem/part you have to worry about and it is a good way to see what kind of flow your getting.