Ok so I have stock ls1 efans on my truck that is twin turboed and am having issues keeping temps down. It climbs to 210 and stays there, pulled a boat with it for a short distance and it climbed to 230 ish.

Any ideas on how to keep it cooler?

Run stock silverado efans, oil cooler, or bigger radiator?

 

get some 07 fans off ebay, get a 34inch radiator, grab the harness for fans, and you should be good. I just did this upgrade last night to my 04 with a 6.0/4L80e. the 07 fans move some major air...

 

I have a good efan harness so that shouldent be an issue. I do feel tho when the ls1 fans kick on that they dont move much air...

Is the 34" radiator a direct swap? What is the 03 stock size, 32"?

anyone running oil coolers?

 

I think the one you have now is a 28 inch, it was a direct swap on my 04 so it should be on yours. the rad and fans dropped right in. only thing I had to do is find some bolts for the efans. The fans bolt where the old rad bolted and the new rad moves the bolt out 3 inches on each side as its wider.

 

Ok cool.

What about an engine oil cooler to help cool the higher oil temps from the turbos? What are you guys doing for that?

 

The old Taurus/Lincoln Mk 8 fans are still the highest CFM fans you can buy...damn near 5000cfm...and they're dirt cheap in salvage yards. They came on multiple Ford cars but I can't remember which ones other than the Taurus and Lincoln. I'd grab one or 2 of those and try it first.

 

I use LS1 e-fans on the stock 28" radiator. It has no issues keeping the motor cool with both fans on low. I have them coming on at 200F and off at 190F. I'm also using a 160 T-stat, it keeps it at 167-172F on the highway. But I don't tow and it usually isn't too hot here, <80F most of the time. What kind of ambient temps are you at?

 

What harness are you running?

My Black Bear harnesses run both fans at low speed and kicks the right fan on full speed when I turn the AC on. I actually have my turbo truck running the pass. fan on full speed at all times and it does make the truck run a lot cooler. If you could have both fans running at full speed, I doubt you would have any overheating problems, unless your radiator is junk.

FWIW, I'm running the LS1 fans with the larger 34" radiator on one of my trucks and it works great.

 

I use a Nelson harness which works the same.

PCM controls both fans on low
AC controls one fan on high
Both PCM and AC will put both fans on high.

 

Always heard about those fans. Any obvious way to identify them?