SDHNTR

Yeah, rad cap was replaced along with everything else. Is there some chance my motor might just run hotter than others because it is rebuilt and bored .040 over? Might synthetic oil help? When is it safe to switch from dinosaur to synthetic?

ChefYota4x4

iTrader: (5)

Before going synthetic and swapping multiple thermostats and, and, ....... I'd make sure you verify/rule out everything mentioned, including testing those easier things like radiator pressure/flow test, thermostat stove top or better test, coolant temp sensor resistance check, verify the CAT is good(if you have one)........ Because, to be honest, I've had MANY 22re's, .... some of them with 340K, some with 100K, ....the most recent 2 motors haven't made it to 10K and I've had a few overheating issues..... Almost ALL of them were either the Radiator/Clutch fan/Stat/ or water pump(Yep, even had a brand new Altrom--made by Aisin-- water pump totally fail and piss out the weep holes within 1000miles).... Even had a rebuild with a clogged IACV and another with a few clogged water jackets at the bottom of the block cause this type of 'iffy, yet not DRAMA' behavior...... Most everything that can cause a temp issue can be verified/ruled out conclusively.....

With my moderately modded 22re, I can pull 70mph on the Cahon pass with the air on in 5th..... No more, but no falling out to 55, either. I made sure that EVERYTHING flows well/works well, together, for optimum flow/performance/economy..... And my temp NEVER, even with 600#, mid summer, heading out to Needles, CA(118*F), rose above 1/3rd on the Temp Gauge. YES, the fan clutch was going off like a banshee, more often, lol... But I'm running a Trailer Package HD 2 Row Radiator(not sure, ask Toyota, lol... it IS a lil different).... Not 3 row, and still no overheating issues.

The only other thing that caused this in a newer motor for me? HG on a slow decline with only 3K miles on it(a shop did it, and they only went to 48#, not 58#, which isn't even enough, lol).... Well, as it slowly failed, it would run hot'TER at times, then normal under moderate/mild load.... not trying to be negative, just sayin, ya know?

I would make a list and recap for us, next, of everything you've 'hands on checked'.....???...

And, good feedback, thus far, btw! Best wishes, SD

SDHNTR

Ok so can anyone suggest how to conduct a proper flow test? Is there a way to do it without any special tools?

How about some other simple tests I may be able to do? I've tested the tstat in a pot, hand tested the fan, and visually verified there are no leaks anywhere in the system. What else before taking it to a shop and/or needing funky tools?

Team420

to flow test a radiator, I always just drained it, leave the lower hose off, and put the garden hose to it... if the water comes out as fast as it goes in, its not clogged.