How to change coolant and trans fluid on 04 yukon Vortec?

[McFatterson]

I do not have money to take to a mechanic so please do not say just take to a mechanic.

Searched and surprisingly could not find a write-up or other info on how to change the coolant on my 04 Yukon. I have 2 gallons of orange Dexcool coolant. Will this be enough along with 2 gallons of distilled water? Is there a bolt or something from the top that I have to unscrew to let the coolant drain?

I searched for a drain plug on the bottom of the radiator but could find nothing... I have an air compressor for one of those coolant exchanger things.... Is it easier to go this route? If so where do I rent one?

I also have to change the trans fluid.... it is way overfilled for some reason... I have no idea how long its been like this. Is there any harm from overfilling the trans?

How do I change the trans fluid? What type of fluid and filter work best(I see a lot of different opinions on this) I'm worried about it slipping over time... I hear this is a major issue on these trucks.

Any help is greatly appreciated.



Edit: Just called Autozone and they do not rent coolant exchangers. The guy suggested removing the lower radiator hose on the passenger side and let it drain that way with the radiator cap open then filling with distilled water, let it run for a bit, drain that and replace with the 50/50. Any opinions on this?


Also any info on where to take old coolant???
Thx

 

[taylorjm]

Here's what I did, for what it's worth, and it worked quite well.

Remove bottom hose at the radiator.
Remove hose from the surge tank.
Remove upper hose at radiator.

Then I took some pvc pipe fitting and found one that fit snug into that upper radiator hose and reduced it down to my air compressor fitting. Then I put about 15psi of air into that upper radiator hose. Everything in the block came gushing out the surge hose. Then I reconnected the bottom hose and the surge tank hose. Filled up the surge tank with 50/50 dexcool to the hot mark, then poured some into the upper radiator hose to fill up the block, and reconnected the upper hose.

Never had to add any more, didn't have to worry about an empty block, didn't have to purge anything, everything went just great! It took just over 12 qts (3 gal) of 50/50 which is the capacity of my system.

P.S. The part I didn't like about just taking off the lower hose is that you don't empty the block out because the thermostat is closed. You just drain the radiator which doesn't hold that much anyway.

 

[taylorjm]

Here is what I used to blow out the fluid in the block from the upper radiator hose.

 

[NorCalBryan]

Here is what I used to blow out the fluid in the block from the upper radiator hose.

That's awesome!

 

[ScottyBoy]

Ok, that pretty much explains how to do the coolant. Now here is how you flush ALL the transmission fluid out of the lines and torque converter. I used Dexron 6, and it took about 12-13 quarts.
http://www.truckmodcentral.com/forums/showthread.php?t=4699

 

[taylorjm]

That's the same way i changed my trans fluid. (I didn't change the filter). The only thing I would add is that I couldn't get the fitting for that trans cooler line out of the radiator, and I was afraid of trying to turn it too hard and breaking something.

So, what I did was...I pulled that little plastic ring on the upper trans cooler line down, then took a small screwdriver and pulled the clip out that holds the trans cooler line in. (make a note how it goes back in). Then I took some rubber hose (sorry, can't remember what size) but it fit right over the nut/fitting in the radiator, and clamped it down. It worked great! Didn't need the new fitting I bought and didn't have to disconnect anything from the radiator except that quick connect trans cooler line. Went very easy after that.

 

[McFatterson]

Cool PVC device... I'll have to put one together and flush it that way.


I found out you're supposed to check the trans fluid level with the engine running so that is why it looked so high on the dipstick.

I called Autozone again and the guy suggested changing the filter and using Dexron 3 along with Lucas No Slip tranny additive (my Yukon has ~80k). The entire change including the tranny pan gasket comes out to $50. I might just go with the Dexron 6 though since it seems to be popular on this site....

Is changing the tranny filter @80k a good idea or could I get away with just a fluid change? Is changing the filter pretty straight forward? I know you have to drop the pan which sounds messy.

Thanks for the help guys.

 

[ScottyBoy]

If you have never changed the filter before, I STRONGLY suggest that you drop the pan and change it.
And although Dexron 3 will actually work, the Dexron 6 is a far better fluid. But then again, its much more expensive too. I noticed smoother shifting after switching to the 6. And my transmission temp dropped on average about 8-10 degrees.

 

[ezdaar]

When I used the fulsh fill method linked above...

the lil plastic piece your worried about breaking, simply lube it up and work the nut back and forth a few times... the oring will slipon the tube thus no need to pop that clip and loose it or acidently cut the oring..

Before dropping pan, use that method to drain the pan. its a hell of alot cleaner when you dont get 4 quarts of hot ass tranny fluid in your face.

Dont use anti slip additive, it only lasts a few hundred miles..
Install a vetter servo and better OD servo.. they last forever and will stop your slipping, on older trannys.

 

[06xl]

Here is what I used to blow out the fluid in the block from the upper radiator hose.

Sounds like your in business make a few thousand paint it black name it gmc easy flush an off to autozone your product goes an I get 8% profit for the business idea