Radiator/tranny flush

**Guerrillakilla13** · 10-20-2012, 07:18 PM

Hi everyone

So I thought i'd ask for all of your opinions... When should I really consider doing a coolant flush? Transmission flush? I have an automatic, 2002 @ 50k miles, I think the time is right but the car is still running perfectly so I wasn't sure if it was too soon.

**SuperSSguy** · 10-20-2012, 07:49 PM

They say that Dex-cool can last X-(thousands) amount of miles? Im still not sold on that id do the recommended service as your vehicles maintenance book calls for- in some instances earlier... It only hurts your wallet if you are doing them earlier then recommended but it will keep your ride happy.

**az gt eater** · 10-21-2012, 01:15 AM

YOu have to remember that you have 10 year old everything. You should be thinking about a lot more than just a fluid change. Your hoses, belts, AND coolant are really old. When you decide to change/flush coolant, you should change your hoses as well. And, flush that rad good.

**az gt eater** · 10-21-2012, 01:17 AM

And, as far as it still running good, that is why it is called preventative maintenance.

**Too Fast** · 10-21-2012, 05:10 AM

Yes Dex-Cool says every 150k or 5 years, pH levels and corrosion inhibitors change. You are way overdue if it's not been done, and PM is a lot cheaper than replacing parts that fail. I'd do a fluid exchange on the trans also, and drop the pan at 100k to change the filter there.

**Chronic442** · 10-21-2012, 08:44 AM

I've still never changed my coolant. I'm creeping up on 50k

Sent from my iPhone using Tapatalk

**Smittro** · 10-21-2012, 09:06 AM

Have the trany flushed around 50-70k.

Make sure the shop replaces the filter as some shops just flush the trany and do not change filters.

I stopped using dex-cool in my 01 camaro after it ate my lower manifold gaskets (have pics) and caused coolant to be injested by my engine.

**2002ssslp** · 10-21-2012, 09:48 AM

I do not know how old my coolant is so I am going to change it before I put it to bed for the winter. Any tricks to bleeding the cooling systems on F body cars ?

**pajeff02** · 10-21-2012, 10:41 AM

Here's the drill:

On the passenger side of the radiator there is a petcock that you open by turning counterclockwise to allow the coolant to drain. Unfortunately, there is quite a bit of coolant that remains in the block if you simply drain the radiator. The block drains are not all that bad to get to. On the passenger side, the drain is located above the starter. Use a 5/16" allen head on a 9" extension (it may actually be metric, but this had the best fit). On the driver side, the drain is a 17mm allen head located above and behind the alternator. The only thing I had to remove was the alternator splash guard. You can purchase a set of large allen head sockets from Autozone for about $12.00.

There is an air bleed built into the thermostat to allow air to escape as the system is filled. I just did a slow fill over time, adding a bit of coolant every 5-10 minutes, rocking the car and bouncing it on the suspension helps work the air out. On start up, just keep an eye on your gauges. You can also feel your hoses (careful of the belts) to ensure that coolant is flowing. If you are going to the trouble of dropping the coolant, it is best to get all the old stuff out. Flushing it is even better (no chemical flush!) and is easiest with the thermostat removed from the housing.

**Too Fast** · 10-21-2012, 02:18 PM

Originally Posted by Smittro

Have the trany flushed around 50-70k.

Make sure the shop replaces the filter as some shops just flush the trany and do not change filters.

I stopped using dex-cool in my 01 camaro after it ate my lower manifold gaskets (have pics) and caused coolant to be injested by my engine.

Not this old tale again. Why did the green coolant eat all the intake gaskets on the Olds 307 V8s from the late 80s/early 90s then? I say it's poor gasket design, not the coolant. Funny how it only happened to that engine series, the GM 3.1/3.4. After I put on new gaskets on these engines, they never failed again. Other engines have random intake gasket failures also, like some Chryslers. I've seen Ford's 3.0 (OHV) leak also. I have no doubt you had gasket failure, I just don't think it was dexcool that caused it.

**Smittro** · 10-21-2012, 08:10 PM

Originally Posted by Too Fast

Not this old tale again. Why did the green coolant eat all the intake gaskets on the Olds 307 V8s from the late 80s/early 90s then? I say it's poor gasket design, not the coolant. Funny how it only happened to that engine series, the GM 3.1/3.4. After I put on new gaskets on these engines, they never failed again. Other engines have random intake gasket failures also, like some Chryslers. I've seen Ford's 3.0 (OHV) leak also. I have no doubt you had gasket failure, I just don't think it was dexcool that caused it.

My 01 camaro did'nt have a 3.1 nor 3.4..

It was more likely due to the age of my old coolant..

I've never seen green do that even after it was never flushed and turned brown.

**Guerrillakilla13** · 10-21-2012, 09:41 PM

Thanks alot for the feedback. Last time I checked (was a month ago), i was low on coolant and the dip stick looked like it was dipped in mud. Should be a great indicator that I need a flush, but the car temps seemed to be okay. I'll get that sucker flushed.

I found a great write up by jay, http://www.ls1.com/forums/f6/diy-coo...-flush-157898/

Question about that though; when the time comes for fill up and drain with water, can I use garden hose water? It's hard water..

**az gt eater** · 10-21-2012, 09:48 PM

No, you want distilled water. And, don't fall for that premixed crap. Its way too expensive. Buy two gallons of water and coolant, then mix it all up in a clean 5 gallon bucket. I label my leftovers, and you will have some extra.

**Too Fast** · 10-22-2012, 02:19 AM

You can get distilled water at stores, and mix you own 50/50. When you are ready to refill your cooling system, you can add 1/2 gallon pure, then 1/2 gallon water, then put a half gallon water into the half gallon of pure anti-freeze, pour that in, then pour half of your new full strength coolant into your empty, pre-mix those, then you have some leftover pre-mixed. I usually label those with a sharpie when I'm done, to save some extra.

**Too Fast** · 10-22-2012, 02:23 AM

Originally Posted by Smittro

My 01 camaro did'nt have a 3.1 nor 3.4..

It was more likely due to the age of my old coolant..

I've never seen green do that even after it was never flushed and turned brown.

Oh yeah missed that. Did these 3.8s have EGRs? I know on the FWD 3.8 it would fail where the EGR tube enters the plenum, melting it and causing coolant leaks/failure. Fix is a new plenum.

**Smittro** · 10-22-2012, 02:37 AM

Originally Posted by Too Fast

Oh yeah missed that. Did these 3.8s have EGRs? I know on the FWD 3.8 it would fail where the EGR tube enters the plenum, melting it and causing coolant leaks/failure. Fix is a new plenum.

Yes the l36 rwd had an EGR with a short chimney pipe that connected to the upper intake plenum.

The RWD upper and lower intakes are cast aluminum.

It has a single bolt mount above the thermostat hole.

**Too Fast** · 10-22-2012, 02:45 AM

Nice lookin' intake. Obviously it didn't melt! You still have that car?

**Smittro** · 10-22-2012, 02:48 AM

Originally Posted by Too Fast

Nice lookin' intake. Obviously it didn't melt! You still have that car?

Thanks! No I don't. I'm looking for my next one though.XD

**Guerrillakilla13** · 10-22-2012, 10:14 PM

Sorry I meant for when you fill up the reservoir, idle for 5 minutes, flush and repeat til the water comes out clean. I should still get some distilled water for that?

**Smittro** · 10-23-2012, 02:55 AM

I know in the old days and on my 3800 I just ran the garden hose into my rad with (petcock open) the engine running till it was flushed then about 3 gallons of distilled water.

Then shut her down and let that drain on it's own. After that I'd close everything off and begin the refill.

Once the system was full test the mix with a coolant tester after it was filled.

Then fire it back up and add as needed and test it again.

However,, with the drain plugs removed on both sides of the LS1, I am not sure running the engine while you flush it is a good idea.

You can check the sticky's I believe there's a detailed proceedure there on how to properly drain and flush your LS1 coolant system.