Hey all,I have a 2003 ram 2500 with the 5.7 hemi 170k miles......so to start off,had to replace water pump couple months ago cuz bearing was bad and water coming out of the failsafe hole and while I was at it I replaced the thermostat...made sure jiggle pin was straight up,truck ran good for a week or so,started noticing temp gauge reading over half....normal was always under half,than just last week it overheated way past half almost to red before I noticed and shut it off to let cool down....come to find out the new thermostat wasn't opening...even took it back out and did the boiling water test and still didn't open...so got another new one this time from advanced auto....and BTW these are the oem 203 degree ones....tried it and it's still overheating but just not as bad....even tried a brand new radiator cap,I tried burping the system by driving front of truck on ramps and squeezing the hoses,fan works,it's full of coolant...took it for a drive about 10 miles and got hot again so I took temp gun,the engine head reads 235 and bottom of oil pan reads 220,the upper radiator hose and lower hose temp difference was about 10 degrees difference....lower hose being cooler....so I'm not sure and tried asking around and no one knows,hoping someone on here would know,hate seeing the hemi sick like this,lol

 

Did they give you the wrong water pump?? If it is spinning the wrong way, it won't move coolant... and the engine over heats.

 

Yea I compared it to the old one it was the same

 

My only suggestion is to flush it out ..... I mean add a flushing T to a coolant line and force old dirty water out.
I have done this several times .... I actually prefer to run some cleaning vinegar in the coolant system .... then after a few heat cycles hook a garden hose to the flushing T and flush it clean .... sometimes it takes a few flushes to actually get it clean ...... Not a 5 minute job ..... It is a non evasive job and actually works pretty well.

It would only take one flushing and by watching what comes out, tell you if worth doing it again. ...... Comes out clean forget it .... comes out dirty flush it again.
Like the old saying, you wipe your **** 3 times to find out 2 times was enough .... flush that coolant system til it comes out clean.

Adding a flushing T into the heater hose to connect a garden hose and back flush all the dirty contaminates out of the system ..... A clean radiator, working T-stat A water pump that cycles coolant. .... your issue is dirt and no circulation.

 

You mentioned changing the radiator cap, but have you checked the radiator itself for clogs or leaks? A partially clogged radiator can cause the overheating issues you have mentioned.

 

Took it to a family friend that's a mechanic and he said everything looks fine but seems like the radiator is restricting flow....it's getting flow through it but not enough so ima try a different rad

 

That sounds like a great idea. You have a 20 year old truck, sometimes they will just build up with crud over the years ..... when you disturb the cooling system by overheating or replacing a water pump etc... it can knock the crud loose and plug up your radiator.
Your friends diagnoses sounds reasonable to me.

I remember a time when I was working and did not have time to play with auto repairs or maintenance ..... It cost me a lot of $$ if my work truck could not do it's job .... I just slapped down the $$ and said get it done yesterday.

Today am retired and have more time then $$ and do things differently.
Here is a flushing T in my Dodge Caravan


Just a very simple easy to install $5 fitting in your heater hose and now you can connect a garden hose and back flush water through your heater core and out the top of your radiator by removing the cap and let it sit and idle in the driveway.

You will be surprised how much dirt comes out .... when it starts running clear I stop.
Then I drain the radiator and fill it with vinegar from the local grocery store. ..... It is a mild acid and not harmful to coolant systems and it cleans really well.
I will fill it with vinegar and drive it this way .... go through several heat cycles and then flush it again and see how much crap comes out of the radiator.
Depending how bad it is, I may repeat the process as many times as it takes to finally get clean vinegar coming out .... I like a clean coolant system and it takes a little time but not difficult or costly.



I understand either way you decide to go ... your choice.
Every vehicle I own has a flushing T in it and has had a vinegar bath .... my chebby truck I did about 8 years ago including T-stat, water pump, all hoses .... It works perfect and no problems with it .... The antifreeze is 8 years old and over due for a change ..... It is just maintenance, it will get a vinegar bath before adding fresh antifreeze.

So I feel you can possibly still fix your current radiator as long as its not leaking .... I would still add a T to it just to clean out the heater core and engine block.

 

Hey all thanks for the help,I found the problem it was a clogged radiator,i bought a new one and took the old one apart and like 60% of the "canals" if u call it that? We're clogged and not moving water....clogged with some silicone,red crust and white scale....so the ol hemi is running even cooler than it has since I owned it...running about 3 needle widths before half way on the gauge

 

Glad to hear you solved that. That's pretty much exactly where the temp guage should read so you're doing good .

 

Make sure if you're mixing coolant from concentrate, that you're using distilled water. Regular tap water causes that crud over time.