COShadow

FWIW, I've had two thermostats, exact same part number (both Toyota OEM, both stamped with 82C (180F)) running in my truck in the last week. The older one that was in there originally would result in a coolant temp of 173-177 running on a 90's day. The brand new one would result in a coolant temp of 198-203 in the same weather. I even put the old one back in to double check, because I was so surprised about the big difference in temperature.

Mt Goat-- Is your thermostat an aftermarket? The Toyota parts guy told me there was only one type of Toyota thermostat for 96-02 4runners.

J2F42C

[quote=COShadow;51514470]The older one that was in there originally would result in a coolant temp of 173-177 running on a 90's day. The brand new one would result in a coolant temp of 198-203 in the same weather.

Most likely due to the old T-stat being stuck open, thus not letting the engine temp get to at least 191 degrees. Anything lower in temperature and the water may not be burned off. Ever seen the oil come out of an auto that does nothing but short trips in its life, hence the engine never gets to operating temp.? Very liquid. Put the new one back in.

COShadow

Normal coolant temp is 176-203. The thermostats are 180 degree F thermostats. Where do you get the 191 number? A good number to know, as someone on another forum suggested is the oil temp, which would tell me if water was being "burned" off. Does anyone have the x gauge code for oil temp from the Scangauge II?

COShadow

^^That said, you may be right, still trying to sort this out.

pendrag

Well, Balls, I'd guess the chart indicates the stability range of their ATF formula. Pretty stable in the blue, somewhat degraded, but ok in the red, degraded pretty badly above and below. You'd have to take it up with Amsoil if you think their numbers are bad. I'm just passing it along for whatever it's worth.




KBALL,
If you're replacing ~ 8oz of the ~28 oz in the power steering system (that's 30%, but I'm rounding to 25% for simplicity), then here's what you get with each change:

Change number (% old fluid remaining)
0 (100)
1 (75)
2 (56)
3 (42)
4 (32)
5 (24)
6 (18)
7 (13)
8 (10)
9 (8)
10(6)
11(4)
12(3)

mt_goat

trd 160*

nexgen91

well here is an update, I went and got a 170 degree stant thermostat from advance and I cleaned them out of max life (I did get the right kind by buying the one in the red jug/bottle with "for vehicles over 75000 miles" on the front correct?) I flushed it out tonight, thing is I forgot to flush the aux cooler (i figure this is not a huge deal, since there should not be a lot of fluid in there anyway), and cycle through the low drive gears before I took it for the test drive (this wouldnt have messed anything up would it, just not give correct fluid level), and when I got back I cycled the gears a few times, and it was a little over a quart low, so I topped it off, now at a ATF temp of around 130 degrees after the drive (water temp is still hovering around 194) the ATF is about half way between the hot marks on the stick. does this sound like I did ok? I still have yet to change out the tstat, because I found that SC pulley in my way and didnt wanna mess with it tonight. Oh yeah if anyone finds out the xgauge code for Oil Temp that would be great to have for my towing endeavor.