New thermostat issue?

Just replaced my '99 5VZFE thermostat with the Toyota recommended unit, same serial number as what I had been running. My old therm never moved off 188 degrees (SCANGAUGE II) except going up steep hills, towing, etc. The new one moves between 195 and 200 degrees, around town, in the winter. My question is will I have any issues in the future since the original therm sat at 188 for at least 10 years and now it's closer to 200. My local mech says he wouldn't worry until it went over 220, sound right?

 

Do you know which thermostat you got? You can get thermostats that open at different temperatures, mines a 180F and I sit between 185-190F operating temp. Maybe yours is a 190F, giving you 195-200? I've never seen a 190F thermostat offered for these trucks though, only 180F or 170F.

Did you make sure the coolant is back to full after the replacement as well?

 

Which way did you position the jiggle valve? 6 o'clock or 12?

 

I still cant believe its 6 o clock. I set every 5VZ to 12, manual be damned.

I dont think it would cause an operating temp change. It would open all the same.

 

Someone actually took the time to remove and replace the thermostat, and took measurements of the temperature on each setting and verified there was a difference, in a pretty scientific way. Maybe someone can link that, its somewhere on TW.

EDIT: Found it https://www.tacomaworld.com/threads...-difference-12°f-for-me.442909/#post-12892345

OP this is probably what happened

 

Crazy. It doesnt make sense, the thermostat should behave the same, but obviously there's numerous threads pointing to otherwise.

The issue is my generation was pretty much you just replace maintenance items without opening manuals, so I never ever had manuals open for timing belts. You just did them, and t stat dingles point up as a rule.

At most I'd torque cam bolts if I did seals.

https://www.yotatech.com/forums/f2/...ing-belt-pictures-pleasure-249481/index2.html

 

I've done it as well, with immediate and obvious results. There are long threads on YotyaTech that are over a decade old, let alone the ones here, where people experimented and had the same results.
If its something OP wants to try, provided he indeed has his at 12, then I'd say go for it. But as always, to each their own. Won't hurt anything if its as 12.

 

I bet the thermostat position is the culprit. I noticed the same after my head work was done. Higher operating temp than before. Checked the thermostat position and sure enough the tech had put the jiggle valve up. Easy fix.