Real simple...
VZ-FE owners only, where does your coolant gauge stay?
List your engine, and what it comes in. (If not obvious, like in your sig)

List if you ever had a cooling problem with it (bad coolant, bad hoses, bad thermostat, bad caps), and what caused that problem. (i.e. like old coolant at some point damaged the radiator, so it clogged and started leaking later on).

If you blew a head gasket, say why it blew because the gasket, and head torque suck(90% of the time) , or because the engine was having overheating problems before hand, resulting in the blown head gasket.

 

My 3VZ-FE is on my venerable (i.e., battered) '93 pickup (148,000 miles now)...

For 12 years, the water temp gauge stayed at exactly 50% of scale (centered over the little thermometer icon) under all conditions.

A few weeks ago it started intermittently sliding up toward redline after 5 - 7 miles on the road, every other trip, with similarly intermittent coolant loss (and no leak I could find).

Diagnosis: Thermostat and thermostat gasket. Both replaced. Except for one minor 'heat-up / short of redline' incident a couple of days ago, that seemed to have done the trick.

Head gasket was replaced under warranty at the 60K-mile checkup. It was showing signs of impending leakage / failure, but hadn't gone out on me.

Except for the thermostat and water pump (replaced at circa 110K-miles) the cooling system is totally original.

 

Mine continually stays one needle width below the center line. Occasionally on a hot day, with the AC on, sitting at a long stop light - the needle may move to the dead center but as soon as I get going again it drops back down to normal.

 

3.0 v6 5spd manual.
Temp gauge normally stays just on the low side of the 'wavy' pattern. Head gasket was just done, no coolant losses. However, about a week ago (temps in the high 80's) it began to creep up to the OTHER side of the 'wavy' pattern. This occured at the top of a very steep incline, after running the last 60 minutes at 80 mph. This is the very first time I've ever seen it move...kinda caught my eye. Temps went back down to normal...no more problem. Temps today are low 90's, so I'll see how that goes, while trying to keep the speed under 70.

UPDATE: Kept it under 80 mph today on the way home. Temps in the high 80's...gauge bumped up to just over the middle cresting the big hill (400' rising to 1000') on my 60 mile drive home. No big deal...just surprised to see the gauge even move

 

88 V6 4Runner, just a bit under half way.

 

Well, I don't have a 3vz-fe, but I have a 3vze, which I'm sure you meant anyway. Not too many pickups out there with camry motors I would imagine, hehe.

Temp gauge stays right in the middle. No matter if its 18 degrees Farenheit or 110, right smack dab in the middle. Even after I broke both motor mounts which completely destroyed the fan shroud (run without one now), still stays the same. 94 pickup 4x4 single cab. Only takes about a half mile of slow acceleration to warm it up, too.

 

3.0 Auto, once it warms up it stays just below halfway mark, NO MATTER WHAT. I had to replace my original radiator at around 50K because it leaked.

 

Half way, in all conditions, no matter what speed or where I'm driving. The only time it heats up is if it's scorching hot and I turn the motor off. Right when I crank it up it's near redline, but within a few seconds the coolant gets to moving and it goes right back down to normal.

 

Mine stays just to the left of the little thermometer symbol and never ever moves. Even in 110 degree desert traffic with AC on. The only time it's gone above that is when I ran a Flex A Lite Black Magic fan. No matter what I did the engine would overheat on slow uphill grades even in cool weather. Went back to the factory fan and had no more overheating problems. I'm on my third radiator after getting a cheap one from Radiators.com that lasted about a year.