@hockeyman ... I negotiated the Home Delivery knowing full well that the additional nominal delivery fee included the option for a decent refund if I opted to have the Freight Return Slip Paper Work later sent to me by the eBay Vendor for making the transaction of having the Freight Carrier contacted and come to pick up the Old Transmission for the return to the eBay Vendor back in Texas. l was afraid that if I mentioned wanting to keep the core transmission...they might get cold feet... and not bend the rules in my favour for what might devolve into a strictly "Terminal Freight Shipping" arrangement that under the circumstances, would have been extremely inconvenient for me and which I very much wanted to avoid.
PLEASE FORGIVE THIS HIJACK... BUT IF ANYONE IS CONSIDERING DOING THIS REPAIR... THIS IS AN OFTEN OVERLOOKED AND VERY IMPORTANT SERIES OF STEPS TO FOLLOW WHEN DOING THIS 4L60E REPAIR:
Remembering that at the time all of this was happening... I was over 65 years old, working on this repair alone and enduring what was essentially an unseasonably frigid (for Florida)
"Ice Cold Rainy December Week of From Hell". During that time-line... I had to lay on Black Plastic Garbage Bag Sections covering big sections of Cardboard to work on under the Tralblazer on sloped concrete driveway for nearly an entire week. While I was laying down there being inundated with one chilly rainfall after another...those Black Bags repeatedly collected and filled up with Storm Water all around me like a Kid's Swimming Pool, but certainly not as much fun for me... as the cold water soaked my clothing and sapped my energy again and again during the entire experience.
Right along with that problem was having to work some very long and very arduous hours on this swap-out, as there were times when things were happening that demanded my full strength and endurance and stopping in the middle of doing such things was out of the question. As the repair neared completion... I realized and needed to seriously consider that this New Transmission deserved a proper Baptism by Brand New Transmission Fluid...and not become poisoned by the remaining
Black Pool of Old Transmission Fluid Mung hiding deep inside the Inlet and Outlet Lines and lodged even deeper inside of the Transmission Cooler.
But to accomplish this... I had to resort to my "Mad Inventor Skills" by adapting an
Aluminum HVAC AC Pressure Cleaner Cylinder with a MAX pressure capacity of 90 PSI... and bend it to my will. I decided the best way to accomplish a Proper Power Flush of the Transmission Cooler was to fill up the Aluminum Cylinder with Transmission Flush, using not less than 6 Pints...Pressurizing one Pint at a Time... one after another... and use the Ball Check Valve on the Cylinder with an HVAC Hose with a Pistol Handle, and modified it to mate up with a long length of 3/8" Reinforced Rubber Fuel line. I fastened the Black Line to the
"OUTLET SIDE" COOLER LINE
(Fluid Normally Flows Towards the Transmission Through This Line) but in this case acting as the "INLET-SIDE" for the purposes of using my
Transmission Cooler Cylinder Flush Apparatus.
Likewise... I attached another decent length of Reinforced Rubber Fuel line to the
"INLET SIDE" (Fluid Normally Flows Away From the Transmission and BACK Inside The Transmission Cooler Through This Line).and from there...I routed that long hose into a length of
CLEAR, REINFORCED ACRYLIC SINK HOSING that went down through a hole I drilled at one corner of the Orange Lid of this Tall Square Yellow Plastic Container to act as a
Catch Basin for all of the SERIOUS CRAP that had accumulated inside of the Transmission Cooler and Lines. After 240,000 Miles...all this Fluid and Mung Residue would soon be rejected from hiding deep within the Transmission Cooler.. BUT NOT WITHOUT A FIGHT!
It followed that I had to drill out a second Air Pressure Relief Hole along the opposite edge of the Orange Lid of the Tall Yellow container in order to allow the ambient air inside to escape as the pressurized exiting used Transmission Fluid might over-pressurize the Recovery Container enough to blow the lid off of it. In order to secure the Fuel Line inside, I looped around several coils of the Drainage Fuel Line on the lid...and then placed several weighty decorative yard stones on top to resist "Newton's Third Law of Motion" ... lest, like a Rocket Nozzle... the hose might react by pushing itself backwards, completely out of the lid to spray Old Transmission Fluid all over the place!
Next...With the Ball Valve on the Aluminum Pressure Cylinder in the CLOSED Position... I induced Compressed Air via my Air Compressor into the the common Air Hose Connector where the AIR PRESSURE GAUGE indicated the fill rate and Internal Pressure of the Aluminum Cylinder...and because I did not want to rupture the Transmission Lines or to damage the Transmission Cooler deep inside of the Radiator...I only filled the Aluminum Cylinder to
60 PSI. At this point everything was ready and in position.
Next...AND THIS PART IS VERY, VERY IMPORTANT....
With all of the Proper Hoses hooked up in the Proper REVERSE Direction...And with all of the line attachments secured with Reliable Hose Clamps...and with 60 PSI bearing down inside of the Aluminum Cylinder holding only One Pint of Transmission Flush...It only remained to
SLOWLY...AND I DO MEAN ....SLLLLLLOOOOOOWWWLLLYYY... Opening the Ball Valve and allow the Transmission flush to gradually enter the Yellow HVAC Hose at an adjusted PSI lowered to 30 Pounds Per Square Inch...allowing the Flushing Fluid to enter the Black Rubber Fuel Line first and then into the OUTLET side of the Transmission Cooler...and by then...suddenly you will begin to hear things Rumbling, Roiling and Rolling while the Flushing Fluid is MOVING deep inside of the Transmission Cooler.
After around 30 seconds of waiting...you can hear all of that TRAPPED CRAP LODGED INSIDE THE TRANSMISSION COOLER BEGIN TO BREAK LOOSE ...And then all of a sudden....the CLEAR ACRYLIC HOSE TURNS JET BLACK...as the Projectile Old Transmission Fluid is Flowing into the shuddering and sputtering in the bottom of the Tall Yellow Container.
It only remained for me to do this
5 More Times...with less and less "Pressure Drama" and gradually, the exiting Fluid Stream became Cleaner and Cleaner until there was nothing but Clean Transmission Flush in view inside the Clear Acrylic Drain Line. It followed that I used several containers of Fresh Dexron in this identical fashion to thoroughly clean out the Transmission Cooler and Lines of any Residual Transmission Flush. When the fluid went through clear Acrylic Hose as a Fresh Transparent Red Stream as viewed with a Flash-light for Back-lighting... I knew I had complete success and now... No Worries about contaminating a Brand New Transmission with the Dreaded "Black Mung".
After you finish installing the new Transmission...with the exception of the presence of the Blue Assembly Grease, perhaps some White Petroleum Jelly and a little bit of Transmission Fluid left inside during the Re-manufacturing Process...this system will ultimately require just shy of 12 Quarts of Fresh Dexron Transmission Fluid. But you will want to add the last few quarts rather slowly after shutting down the system after it warms up from idling in park. Of course...when you finish the job, you must check that the fluid level is nominal often...and using a bright flash-light while looking for leaks on the passenger side of the centre area where the Transmission Fluid In and Out line connections are located is a must. Also make certain you push the two Transmission Cooler Lines at their bend points near the radiator firmly into their moulded lock-down bracket points.
Check the rear of the transmission take off seal at the drive-shaft for leaks later on after your Test Drive. As you install the drive-shaft very carefully...double check your tightening of the fasteners on the rear differential Universal Joint. You'll need to take the vehicle for a Test Drive...driving very slowly and carefully while listening to the new transmission shifting up and down the ladder of gear clusters to allow the gears to change and give you the chance to feel how well it works. DON'T BE TEMPTED TO RACE THE ENGINE TO 5,000 RPM AND SLAM THE SHIFT LEVER IN DRIVE. It seems absurd to have to even mention how foolhardy it would be to do this... But you would be surprised how many people will actually want to do this!
For God's Sake.. Don't drive this equipment hard with the idea that this constitutes a "Testing Procedure". Make a point of taking the vehicle to the Local GM Dealership to have the necessary $99.00 CASE Relearn Procedure done... there is no way around this requirement if you want the New Transmission to feel "at home" in your Trailblazer. When I took mine in for this procedure... The puzzled Transmission Tech actually came out from within the Service Bay Area and asked me, "Did YOU install the Transmission into the White Trailblazer...Yourself?" I smiled and said, "Yup..." He smiled right back at me and then he said, "It looks Really Good...You did a Great Job!" Ahhh Yes..."Praise From Caesar..." ...Is Praise...Indeed. :>)