Changing Fluids Need Some Answers PLZ

Thur/Fri I going to be changing all the fluids in my 98' T/A. Background, 112k miles All stock, no mods yet


Oil - Going to change to Pennzoil Platinum - till Sarge test oil comes in


Now onto some questions:

Radiator - What brand should I go with? i live in AL and if it ever gets cold (below 28 degrees we all have serious issues)

I will be bleeding breaks to? Use any ol' Dot III? (currently very black in color)

The main reason for all of this work, I will be changing the Master and Slave Cylinders out, have mushy pedal, check the fluid and it is very black also)

I also want to change the oil in the rear end. Any suggestions? I know to stay away from RP.

Thanks ahead of time.

You are going to get answers from both the DexCool camp and non-DexCool camp on this one. I went with GM Approved DexCool that you can get from Shell, Havoline and others. Saved a bit of money versus buying it from the dealership.

Just be sure to do a thorough flush -- I removed my thermostat from the housing and dropped both block drains. Flushed the system a few times with distilled water until it ran clear. Do this with the temperature control set to "Hot" and your blower on to also flush the heater core.

The service manual advises against any chemical flush. Also make sure you don't pour cold water in a hot engine. Let it cool down between flush cycles. If you are changing out hoses, a remote hose clamp tool is highly recommended.

Radiator- dexcool, prestone works for me but NO ADDITIVES. Don't add like cooling system lube or protectant
Brakes- Valvaline makes a dot3 synthetic that works great on my lt1 to ls1 brake conversion.
Rear- I use valvaline 80w 90 syn and GM's limmited slip additive. There are others but everytime I have used them I have problems with the lsd not working right after several months.
Power steering- again I use valvaline but I use 80% power steering fluid and 20% valvaline dex/merc trans fluid helps clean the system and after a month I suck it out of the resivor and replace with straight PS fluid.

As for the brakes I would use a turkey baister to suck out the fluid in the resivor and then fill it and bleed from the right rear to the left rear to the right front to the left front. See if that helps the feel first but always check you pads to see if you have a stickey calliper.