I was going to change my trans fluid and filter, but Ive heard that its better to have the system flushed instead of the routine change. Any truth to this? If so, how much is a trans system flush and refill?

 

I would say that flushing, as opposed to just changing the fluid in the pan, is much better. When you flush, you are changing ~16 quarts with fresh fluid, changing the pan, you are only changing 2 - 3 quarts. It is a lot more expensive ($80-100) but it is good piece of mind. Just make sure they top off the transmission with the engine warm and running.

 

16 quarts?????? Holly crap what kinda tranny do you have? Just rebuilt mine and it took 12. Anyway....yeah a flush is better and stay with conventional oils.

 

4L60E capacity is 21.6 pts..

Or 10.8 Quarts...

 

Hey Motorhead..... how much?? damn. I just put mine in 3 months ago and had it totally rebuilt. The trans shop told me it will take about 11.5 or so but I got an auxillary cooler. I put in 12 quarts and it was full. What am I missing???

 

Motorhead's figure is in pints.

 

Only word of caution ... no argument that 100% fluid change is generally the best course, but if you've got a lot of miles on your transmission, set aside some money for a rebuild. A flush will tend to remove the contaminants that may be helping your tranny do it's job. Happened to me on my 1991 Vette, within a couple of months after a flush ... gone. Granted, it was going to fail sooner than later, but the flush certainly hurried things along.

The shop that rebuilt my transmission told me that the flush on GM transmissions is not necessarily the best idea, although it seems to work well for other makes.

I know it sounds backwards, but I know several GM truck owners, including my dad, who never change transmission fluid, unless it gets burned or water somehow. My dad's '92 1/2 ton 350 went 240K miles before needing a rebuild on the transmission. I can only remember it being changed a couple of times, and that was just a pan drop.

 

You guys probably aren't this cheap but I used to do my own flush, back when I had an automatic. I used two containers that had enough capacity to hold the amount that the transmission held. I disconnected the fluid line to the radiator and put it in the empty container and put the full container (which fed out of the bottom) into the return line. I set the full container about 6' up in the air to give it pressure from gravity. Started the engine and let it idle. When the top container was empty and the bottom full, I was done. You can see the color change as you get to the end. The only this this doesn't do, of course, is change the filter in the pan. Worked ok though.

 

1fast95z might have a tranny cooler so that might add more to the flush

 

Change fluid! Dropping the pan allows you to get a visual inspection of what kind of shape the transmission is in. If something is going wrong in the trans, you'll see signs of it in the bottom of the pan...IE metal or black film. The metal would signify something rubbing metal to metal...The black film would signify burnt clutches.

Frank
All-Trans Transmissions