What would the best way to flush the old coolant out of my truck so that I can switch to synthetic??

 

Low pressure water. Flushing the system will most probably lead to leaks - get ready

 

Go get a flush kit.

 

Get some good cooling system flush. The powdered stuff works best. Drain the coolant, fill it back up with water and run it. The flush will have directions on it. Follow them or it will not work. Sometimes you have to run the engine at temp for a couple hours. Good luck.

 

lol we seem to use different technologies

 

Sometimes the crud's the only thing keeping it from leaking! You have to roll the dice for the sake of the engine. If you switch to distilled water & antifreeze, your coolant system will last longer, not collect crud, and work more efficiently. But the first time you add tap water again, the problem's will start again! W/ tap water, solid particles & minerals actually bakes scale deposits onto the inner cooling pathways of the engine block. During thermal expansion/ contraction of the engine metal surfaces, some scale breaks away to wreck havoc throughout the coolant system. What doesn't, insulates, impeding thermal transfer from the block to the coolant. This will reduce the life of an otherwise healthy engine dramatically. Antifreeze acts as a suspension agent until content exceeds it's capabilities. This state accelerates as the chemical properties of the antifreeze become inert, then only contributing the sludge. Think of tap water as poison!

 

ymeski56, I wouldn't be able to say it better. But - if we're talking about flushing, there are 2 ways. First, like most of you do, is to apply some chemical flusher, which is generally right except one thing - like you said -

So applying cleaning chemicals to any hydraulic system may lead to having pretty close sexual relationship with it, like tightening/replacing/swearing/tightening/replacing and so on until it will get totally satisfied. It's really the right way, it usually ends up with a clean and strong system. What I suggested is not that right, but it causes less problems, though the system will be not that clean. In here garden water hose is being connected to the engine, with drain plug removed. It doesn't work as good as chemistry, but it greatly reduces the risk of following leaks.

 

The 10 min. stuff is the most aggressive, causing larger pieces to break away & dislodge, manytimes collecting at the bottom of the radiator, too large to be passed out through the peddock valve. The stuff you leave in over night, is less aggressive & desolves the scale into a fine silt, holding in suspension for better flushing. I've heard (and had) the most unhappy endings when the 10 min.fast flush was used. For people whose budgets can't accommodate an untimely hit, I'd lay off the chemicals & stick w/ the hose & refill w/ distilled & antifreeze to at least stop any further degradation of your cooling system. If your seeking a real improvement, go w/ the slow acting stuff. For some reason springing a leak after a chemical treatment seems to be directly proportional to one's inability to financially deal w/ it at the time. Think of the scale as cholesterol & the chemical treatment, Lipitor. If you can deal w/ the potential side effects, that's the way to go. But at least a hose flush & switching to distilled w/ antifreeze will stop scale progression. I bit the bullet & went w/ the slow formula when I first got my used truck 4 yrs.ago because I wanted optimum cooling to offset a fairly aggressive additional base timing increase. Switched to dist. & a/f. I don't foresee the need to ever use a chemical agent for flushing again. I do guarantee, continued use of chemical flushes to offset the scale resulting in the use of tap water will result in at least the radiators early demise (& waterpump, freeze plugs, thermostat). Well water is x2 as bad!!

 

Starting to sound like Charles Bukowski !

 

Synthetic what?