thunder550

iTrader: (70)

I posted a thread about colder stats awhile ago, but it was just a general question thread. Now I am considering going to a 180 stat. I want to go colder, love the response when my truck is still warming up and is around 180 or so instead of 195. I do have a one question though:

I have a cooling problem when towing up hill under boost for a couple miles. I had a whole other thread about this, for those who remember. To recap, when I am towing up hill under boost, no matter what speed, my temps will go up to 230 or so, then come back down quickly once I hit the flats. I have tried all kinds of different things, but nothing works. This started once I went to the 34" radiator and e-fans. My question is: Will going to the 180 stat make things worse?

Are there any other considerations? I know a lower temp stat is not really a big deal, but I'm hesitating only because of the overheating problem. I don't want to do this if the problem will get worse. I live in AZ< summer temps are 115-120 during the worst part of the year. Thanks guys.

Bish

I can't think of a reason why going cooler could cause an overheating problem. In fact, I would think it would definitely help. I've been running a 180 for 130K and mine definitely runs cooler with the cooler tstat. Now I don't have a blower so its not a fair comparison but my temps particularly when towing went down with a 180.

02sierraz71_5.3

iTrader: (2)

the 180 stat should help if anything

have you flushed the cooling system, wht sort of coolant did you put back in with the radiator swap? How high up does it go with the towing? any logs of it?

Leroy_454

If you use a 180 stat, you might want to lower the temperature that your electric fans come on at.

ranwalk

iTrader: (1)

Going to the 180 should help some. Electric fans are not the best for towing applications, thats probably why your running hotter when towing up hills. A mechanical fan clutch is better for that. You may want to get the fans hooked up with a manual switch that will turn both on high speed when towing. That may help it out.

NJAV

What would ultimitely be the deciding factor between a 180 vs. 160 thermo?..Just curious.

Dave

jfree81762

Do those high-flow TStats do anything?

thunder550

iTrader: (70)

OK cool I think I'm gonna do it then. I will change the fan temps to compensate...what would be good? On at 185 off at 175?

I wired up a manual switch for turning the fans on high last week, towed with it yesterday and it helped a little but not much. And no, I don't have any logging software so I can't do that yet. I think HPT is in my future but I'm about to close on a house so it will have to wait for a little bit.

I had the stock radiator flushed about 2 weeks before I did the swap, so I re-used the coolant that came out of the stock one. It was Dex-cool, whatever GM recommends cause the dealer did it. The 34" radiator I bought brand new from Performance Radiator. I topped it off with dex-cool/distilled water and did the heat cycle thing to remove any air pockets. I also drilled out the small hose barb on the top passenger side. The only thing that I have left to try is removing the in-radiator tranny cooler to see if maybe it helps out a little. Both the coolant temp and the tranny temp go up, coolant to 230-235 and tranny to 210. I figure if I get 210 degree trans fluid out of the radiator it will work a little better.

The only reason I thought a cooler stat might worsen the problem is that it would cause the cooling system to go open loop sooner, which wouldn't allow the coolant to sit in the radiator long enough to cool down. I could potentially see that causing temps to get higher, but that's what my question is. I really have no idea.

OBXMarine

iTrader: (2)

I've had the 180 and 160 degree thermostats in my truck. I saw 0 change in temps with the 180, but with the 160, my ECT is consitently 172 degrees.

SSlow 4.8

iTrader: (4)

Yea, that would be about right.