I found a nearly new three core brass rad in the wrecker a few weeks ago for my 91 Caprice Classic. I had the rad checked and cleaned at a local shop. I was about to install the rad when I noticed it didn't have the socket for the level sensor. Can such a thing be bought and added to a rad? I looked at Rock Auto but couldn't see anything listed for my car. Thanks.

Bump ... still wondering if anyone has done this.

You would have to dismount the tank (radiator shop again), cut a hole, and braze in the level sensor bung. It would be a lot of work (again) for a level sensor.

Couldn't one be added to the recover tank easily? That's where the factory puts them isn't it?

The factory puts them half way up the tank on the right side of the rad. Putting a level sensor in the overflow would be ok, but I don't think it may always indicate a rad leak since fluid is drawn out of the reserve as it cools. Of course it would have to be below the 'cold' line, but if you have a stone go through your rad when it's still cold, it may be too late for your heads/engine by the time the fluid is drawn into the empty rad. Also, I think there is some liquid lost to evaporation over time, so the sensor would give a reading for a non-existant emergency. And, last, but most importantly, since our Chev's handle like BMW's (LOL), the sensor on the overflow would always be going off while we're flying around corners at tremoundous speeds only seen at the Brickyard!

I looked in my GDI rad book, but didn't see a brass rad that fit this car that had a level sensor. I would have thought that such a beast would have come in a Buick Roadmonster at the very least.

The rad isn't in the car yet, so it's no problem to add the bung. I thought someone may have a make/model for the bung if it is available as a separate item. The current rad in the car has plastic tanks so the bung is molded into the tank. I've make my way back to the rad shop to see if I can get a bung. I have torches, so it's no problem to solder the bung into the tank. Thanks.