Ok guys... ready or not. Mechanic Dan got the new radiator for me.
Everything looks identical except one thing and between the two of us we called every possible source today. All confimed that the radiator was the correct one.

The one thing I noticed was the original radiator core was 1 1/4inches and the new one was only 1 inch. Every place is calling for the replacement to be 1 inch thick.

I was pretty adamant about the radiator ... Dan understood and we checked all sources possible via phone.

And I'm thinking that maybe now the wrong radiator is in my car.

All that have replaced ...any information would be helpful.

Last week the temperature on my car started to suddenly creep up although I replaced the water pump and thermostat while replacing the harmonic balancer. Instead of having the radiator cleaned, I opted for a replacement from Radiator Express on the web. Although they are in the East coast, they have a distributor in Seattle and was able to pick up the radiator the same day. After replacing the radiator and drilling the thermostat the temperature stays around 190 degrees even with the A/C turned-off. I have never had any luck having the newer generation of plastic/aluminum crossflow radiators cleaned, therefore the reason why I always replace them. Also, when I replace the radiator, or rebuild any engine, I add the GM cooling system pellets to the cooling system. They are recommended by GM for any of their replacement Goodwrench engines and any time you overhaul an engine with aluminum heads or block such as the LT-1, LS-1 or LQ-1. Even Jaguar reccomends the addition of a copule of bottles of Bar'* Leak to the cooling system for any engines that are rebuilt. They are harmless since they are organic; they are good in selaing any minor problems in the cooling system and will mix with the coolant.

The main problem I have found with cooling systems in late model cars is the mixing of Dex-Cool with the standard green coolant. Many years ago, the wife took her mini-van to have the oil changed to a quick lube and they mixed both coolants when the mechanic topped of the reservoir. A couple of weeks later the van started to overheat since the coolant turned into sludge. It was a hazzle, but the shop had to pay the dealership to replace the engine, radiator and heater core with new ones since the van had only 9K on the odometer and it blew both head gaskets dumping all the oil in the crankcase. They tried to claim it was not their fault however, they had billed her for the coolant.

ssei1995... Not sure how your story relates to the thread...but I've got a couple questions for you. How thick was the actual core of the radiator you got from Rad Exp?

I'm attempting to get real time dimensions since I know what came out and what every shop I could check has for a replacement.

Was just sharing my experience both with the radiator and Dex-Cool.

The replacement unit from Radiator Express appears to have a thicker core. The internal cooler trans cooler is a 4 line unit, the one on the OEM radiator that I removed is only 3 lines. It is 1/4" thicker than the OEM.

and that 1/4 inch thicker makes the actual measured dimension?

1.0" Thick Core (OEM), 1.25" Thick Core Replacement.

Guys, there is another alternative to complete rad replacement - get only the plastic tank replaced. I took my rad to a rad shop, and he replaced the driver side tank, cleaned and pressure tested it (they must use a geniune GM tank to rad gasket, though). Cost me less than 1/2 of the new rad price. Some opinions are that it is better to do this than get a new rad since the OEM rads are the highest quality.

Put it in, and seems to be working like a charm. I did manage to damage the transmission line that goes into the lower rad since it was rusted. Got the replacement at the dealer.

BTW, I went back to green (Sorry, don't mean to fire up any further debate).