99 Regal GS - Couple minor questions

[eccs19]

I've got a 99 Regal GS. (Love the car)

I need to change my termostat. I've changed lots of thermostats, but never one where the system needs to be bled. Any tips / tricks? Where is the bleeder for this?

One other issue that happens once in a blue moon. With performance shift OFF, sometimes if under 3/4 throttle, the shift from (I'm going from memory here) 2nd to 3rd gives one heck of a bang. Almost enough to break the tires loose. Should I worry, or not, as it is infrequent.

Thanks!

[BNaylor]

Welcome to AF.

The bleeder is located on the thermostat housing. Just follow the upper radiator hose towards the engine.

On the performance shift off issue what is your mileage and is the bang more like a hard or harsh shift?

[eccs19]

Originally Posted by BNaylor

Welcome to AF.

The bleeder is located on the thermostat housing. Just follow the upper radiator hose towards the engine.

On the performance shift off issue what is your mileage and is the bang more like a hard or harsh shift?

Thanks for the bleeder info. Does this car require special coolant when topping it back up?

Mileage is just under 200,000 km. When I first got the car, I took it to the local tranny shop, and they were impressed with how clean the fluid was. It is more like a hard shift, but you can hear it, hence the bang.

[BNaylor]

It uses Dex-cool coolant. If this is being currently used then stick with the Dex-cool. It is orange in color. Do not mix Dex-cool with other coolants to include extended life on the market or you will get a sludge build-up. The other option if status of coolant is unknown is to flush the cooling system and get rid of the old Dex-cool and use the regular extended life coolants like the Prestone Extended Life.

The shifting sounds abnormal to me. My Regal GS doesn't do it or at least no bang when it shifts from 2-3. When you get a chance get it scanned with a trans capable scanner and see if any DTCs are stored like P1811. It does not trigger the SES/CEL light. You may have a pressure control solenoid (PCS) issue.

[eccs19]

BNaylor, I removed the rad cap to check the color, and it is orange, but I think someone must have mixed prior to me owning the car, because there is a LOT of slug built up in the rad. (at least near the cap area) Is there any additive you would recommend to add to clear the slug up, so then I can flush the system, and add the Prestone Extended Life coolant?

[BNaylor]

I use Prestone Super Flush. Add it and run it per the instructions before flushing. We have a cooling system flush procedure if you need it. Also, be sure to clean out the plastic coolant reservoir tank.