I have a 97 chevy 454, The temp is a little confusing to me, running down the highway temp. sits at about 210, sitting still or parked running it temp runs about 180ish. I plan on doing a eletric fan, but just throwing this out there to see who knows what i can do to help or if anybody has the same problem, and whats a good temp it should be normaly just driving or pulling a load.....

210 isn't that bad. A lot of vehicles run 200-210 from the factory (hotter engines burn fuel more efficiently) to reduce emissions. It's kinda odd that the temps go up on the highway, it's usually the other way around for gas engines. Although, if you have an automatic transmission (that uses the radiator as its cooler) it could be generating the extra heat depending on load, slippage, etc. I think a little more info would help us point you in the right direction.

ummmmm......when i bought the truck it only had water in the radiator it ran at only 180 and no higher, one of the hoses had been cut and had and rigged back together with some hose clamps and whatever witch leaked, so i fixed that (just the hose) but left only water in it. Before this last winter that shitty peice that gm installed in the top of the intake that always get brittle and breaks had a leak, sooooo i took that apart witch was a all day job trying to get it all out, replaced it and put 50/50 back in it, thats when it started running hotter........sorry i left that part out

Only thing I can think of is either the mix is off or you somehow introduced trash into the system. I would drain the system (use a strainer under the petcock to see what's coming out) and flush the hell out of it. I usually flush for at least 30 minutes. Last idea, maybe the T-stat is starting to stick and not getting quite all the way open.

yeah I'd flush the system my toyota would run cool at idle allday long but once I started running around it would heat up and if I was on the freeway it run real hot almost scary hot so I flushed the rad and it was a little better so I ended up replacing the rad and we cut open the old one and it was plugged with stop leak stuff. I'm betting with the haybail repair job on the hose your po was a quick fixer and he fixed the heater core a few times. you might end up replacing your heater core also

Sounds like a flow issue, what kind of water, tap or distilled? What kind of coolant, orange or green? The mix should never be 5050, but depending where you are changes your mix. If you have calcium build up from tap water, u need to flush the system and remove the contaminants. Do you have a history on the mechanics of the truck? Sounds like the last guy was either broke or not too sharp.

If its a 97, then it should be green. The orange coolant only came into use once GM started using iron blocks and aluminum heads. The orange helps to prevent electrolysis due to dissimilar metals.

There is nothing [i]wrong[i] with running a 50/50 mix, but the mix should be tailored to your specific conditions. If you have a real concern with cold temps and your block freezing and cracking, then that mix is fine ... but if max cooling is your objective and freezing is not a real problem (like here in FL), then you would be much betterr off running a 75/25 or 80/20 mix of water/anitfreeze since water is a much better coolant than antifreeze. You can even go as low as 10% antifreeze and still retain most of its corrosion protection properties with a slight increase in boiling point. There is also another product called "water wetter" that you can get at most parts stores that can decrease your temps by 5 - 10 degrees. Increasing your water to antifreeze ratio can account for up to a 20 degree reduction in coolant temp.

I also agree with the others that it sounds like a flow issue as well. Generally if you get increased temps on the road, it generally points to poor coolant flow (t-stat, plugged radiator, collapsed radiator hose, water pump going out) and the higher engine temps/speeds overload the cooling system that isnt taxed as much while driving around town. Increased temps can be caused by tranny fluid, but you should have dedicated oil and tranny coolers on your truck in addition to running thru the radiator, and if it locks up in OD then your fluid should stay nice and cool. All that said, no amount of flow will help as much as increasing the amount of water in the system. You even said it ran cooler before you put the extra antifreeze in it.

Also, 210 is not really that hot at all. My 2006 TBSS runs at 210 all day long as set up by GM for emissions. Remember, all the laws of physics (boiling point) go out the window in a cooling system under pressure. The added pressure raises the boiling point much higher ... this is why you never take the cap off of a hot radiator ... as soon as the pressure is released, it could flash boil and that just dont make for a good day!