So it seems like I'll have some free time soon to finally change out the leaky radiator in my I35 and can avoid paying my indy to do it. I'm still debating whether to go with Koyorad or some other brand like TYC off Rock Auto. I know I'll have to get new fan shroud bolts for the Koyorad since it seems the OE ones won't fit.

Since the block drain plugs are basically inaccessible on these cars, I'm going to flush all the old coolant out of the system via multiple distilled water drain & fills through the radiator. So after the last drain, the engine block will be filled with distilled water and the radiator empty. Since the system capacity is a little over 8 qts (including the overflow tank) and the radiator comprises about half this capacity, I plan to dump 100% antifreeze into the radiator until it is full. Once the engine runs, the block and radiator will mix and the engine should have pretty close to a 50/50 coolant mix. Do I have this right?

I originally planned to use Zerex Asian coolant, but it is only sold as a 50/50 and this will throw off the mixture. It seems that the newer blue Nissan LLC also isn't sold as a concentrate, and neither are Honda blue nor Toyota red. I only want to use an Asian vehicle spec'd coolant so what should I do here?

 

Go buy the cheapest long life green coolant at the store and call it a day. I hate to break it to everyone, but coolant is coolant. The expensive stuff is just for really long life b/c bums don't ever flush it.

 

I've heard people say this before but it's widely known Japanese coolants have a unique chemistry. Their coolants have certain phosphates and Hybrid Organic Acid Technology (HOAT). Most importantly, they lack silicates, nitrites, borates, amines and 2-EHA (found to dry out gaskets in cooling systems). Most all makes/models coolants you find at Autozone or Walmart lack silicates but are devoid of everything else spec'd for Japanese cars. I know people are going to say they run generic coolant with no problems but I'd rather use what the engineers spec'd for my car and sleep better at night by doing so.

 

This is news to me, i just bought a KOYO radiator, why wouldnt an aftermarket OE replacement work with the fans, or is it just the bolts??

 

I have put 3 Koyo radiators in my Maximas, my 94, my 97 and my 2000.

I didn't have any problems with them. They all went in like it was a Nissan part.

 

thanks Dennis!, this is what one would assume with an aftermarket OE replacement, but you never know! thanks!

i have a hayden 404 aux transmission cooler, which mounts to the main radiator. so I gotta see if their fasteners are reusable

 

heres the install hardware, i wonder if I can just do zip ties... hmm it dosen;t look like those black things are reusable.

 

In this Radiator Replacement Writeup, several people said the original bolts that attach the fan shroud onto the Koyorad didn't fit so they had to hit up Home Depot to find new bolts. Maybe the newer radiators they're selling took care of this problem...?