I too would recommend going to a larger 34" rad, that helped my temps stay low.

 

Dumb question, but you do have the fans pulling right? Do you have a tranny cooler? That would help a bunch by taking some of the load off the radiator.

 

I dont think the smaller radiator can handle the temps even with a 160* stat and LS1 fans. During traffic my temps will reach 200* and I have LS1 fans and a 160* stat. But on the interstate they will go back down to about 175*. I think a larger radiator will be needed to make the temps stay steady in traffic.

 

Not really. I never had any problems with mine even when I towed over 6000#'s . During that time I was running a stock 4.8/5.3 core radiator, 160* t-stat, LT1 fans. NEVER had problems even in August heat in the Texas hill country. The only reason I have the 6.0 radiator in here now is because I broke one of the cores with a pull through zip-tie that finally rubbed it to the breaking point.

 

You have headers right? With my stock radiator and 14" fans i never saw over 180*, even in the summer. TILL i got my uncoated headers on, and now 210* is not uncommon in summer heat.

 

yes Greg the fans are pulling
and they are pulling air pretty good I can stick my hand in front of the grill and feel the air being sucked through.
yes I do have a trans cooler.
how much would a 6.0 rad be. would it be worth finding one in a junk yard?
I havnt had this problem before, even with the stock fan setup.

 

I dont ever have problems with it overheating, but it will go back to what it ran from the factory in heavy stop and go traffic, even with the e-fans running full blast and the 160* stat.

 

xlr8nss asked if you're using the stock guage to get your readings, i did'nt see an answer. the stock guages can be 10-15 degrees off the actual reading, i've seen 200 on the gauge when logging, efi live is showing 178. as far as the higher thermo, correct me if i'm wrong but does'nt the thermo just open or close ? a 180 thermo will just open later, it does'nt slow the water down any more. i think that only applies to the old running without a thermo [to cheap to replace it] thing, which you can't do on these trucks. if your temp is spiking for no arrent reason your thermo could be sticking shut or as has been said you could have clogged radiator or collapsing hose. does your truck have those two plastic covers in the bumper ? mine did, i took them out looks like it lets more air to the radiator. also in hot weather running more water than coolant will help dissipate heat. in my old truck i ran about 60 water 40 coolant and "water wetter" the radiator had been previously abused and was partially clogged, but never ran over 190. it also helps to spray the bugs and dirt out every once in awhile, it's harder for the rad to dissipate heat if it's filthy. i have the fals and hav'nt had any issues with over heating even when towing in 90 plus temp. e

 

no not running a stock temp gauge

 

ebay is the place! I grabbed one from there. Apparently it was from a 1/2 ton Suburban...it's the 34" one!