primalurges

If it's just happening at highway speed he may have air in the system or a partially clogged radiator or both.

fords forever

thing is a mess, he had a power flush and it made it worse, as it moved all of the crap into the radiator, but i expected that as it happened to me before, now he in process of getting a new radiator, water pump, hoses and belt. is better he does it instead of messing around because i am 1500 miles away and can't fix from here. he needs for towing and backup vehicle. thanks for advice, and YES, looks like mud in it, he bought it used and had it for 2 months, good vehicle otherwise but you never know.

Mod (Ret.)

Who's doing the flush??? A good/reputable shop will first use a flush agent added in to break up/disolve the crud so that it will flow out.

Sounds like the shop (?) he used simply applied a hose to the degause (overflow bottle) and tried to clean it out with a simple water flush. Not good.

fords forever

talked to him last night and after second flush it made it worse, but it was as i expected, all of the crud has now clogged the radiator, know from experience as it happened to my dodge, so he is getting radiator, hoses and water pump changed while the radiator is out for piece of mind. only thought this happened to DODGE trucks.