I put in synthetic Dextron VI a couple of years ago. No notable change.
Transfer Case Fluid Question
- Thread starter JPVortex
- Start date
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I mentioned this a couple posts back, but GM is no longer licensing or producing it. I think the Dex/Merc compatible stuff is about the best you're going to get other than the GM part numbers I posted earlier for specific systems.
I was shown a little trick to fully flush the 4L60E transmission also. Find a tired old radiator in a wreck with an automatic transmission and harvest the UPPER transmission fluid line that is connected to it. That upper transmission fluid line is the radiator outlet that is returning transmission fluid back to the transmission. Make sure you get about 6 or 8 inches of the metal tubing. Connect a 3 foot long piece of clear tubing to your new treasure and connect it to your upper trans cooler line radiator outlet with the other end of your clear tubing in a bucket. You can start your engine now and come out and watch the transmission fluid being pumped into your bucket.
Watch closely!
After about 30 seconds the oil coming out will sputter as you run out of fluid from in the transmission pan and you will need to stop the engine and carefully put more transmission fluid in.
Watch closely!
After about 30 seconds the oil coming out will sputter as you run out of fluid from in the transmission pan and you will need to stop the engine and carefully put more transmission fluid in.
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You want to repeat this process several times and watch the color of the transmission fluid that is draining out through your clear tube. It will be dark at first but once all the old dark fluid has been replaced with fresh bright red fluid you will have replaced all the fluid in the pan, transmission and torque converter.
Once you are getting bright red transmission fluid coming out you want to make sure you have restored your fluid volume back up to the proper level.
Pretty nice. Changed all of your transmission fluid and you didn't have to take the pan off the bottom of your transmission.
My 1998 C1500 had about 205,000 kilometers on it when I bought it with a very sick engine so I wondered about the transmission. I wanted to see the contents of the pan to see if it was as tired as the engine. Turns out the transmission was in very good condition.
