Alright guys, i was checkin the tranny fluid in my car, and it looks like it's time to do a flush on it...i have a 700R4 and was wonderin how hard it is to flush out the tranny, and what all it consists of? i am also wondering about putting synthetic fluid in it when i refill it up...

 

You can't technically flush the tranny yourself on most cars. Your are supposed to take it to a shop where they hook up a machine and it does it. The only thing is, for our cars, you can flush the tranny yourself. If you want all the details just ask and I'll post it.

It would probably be a good idea to put in a new tranny filter and gasket since you're probably going to have have all new fluid in your tranny (if you flush it). Another good idea is to install a drain plug kit in your pan. I did and I love it. I haven't used it yet but it makes things a whole lot easier in the long run.

Also, I'm not really sure if it's a good idea to put synthetic fluid in there. There are always HUGE debates about regular vs. synthetic fluids. I would probably just stick with regular, though, since your tranny probably has a lot of miles. Just put in whichever you want. It's not really going to hurt it either way.

 

would it be more hassle than what it is worth to do it myself? altho i would really like to learn how to do it myself, if i can take it to a shop and have them do it for under 60 or 70...

 

It's not a huge hassel to do it yourself. You can get a filter and pan gasket kit from the autoparts store. I would also suggest sticking with regular Dextron 3 sicne that's what it is running now. I run the Advance Autoparts brand stuff myself and it works just fine.

 

The process in 12 easy steps:
http://www.amsoil.com/faqs/faq8.htm

I'll never use "regular" ATF again. Synthetic is so much better, it doesn't make any sense to risk a $1200 (or more) transmission over a few dollars. If your tranny is on its last leg, that's a different matter - fix it and then fill it with synthetic.

 

With the 'home-made flush', it works because when the cooler line returns the fluid to the transmission, it just dumps the fluid back into the pan. That's why you can unhook the fluid return line- because you're pouring new fluid into the trans pan, and keeping the trans pan full.

I'd actually like to change those directions a bit, but it means more work. The best spot to unhook the cooler line is not at the trans cooler (passenger side of radiator), but from the transmission itself- and you want to unhook the RETURN line.

If you just unhook the line at the cooler, you're not getting that extra bit of old fluid out that will be in the cooler line that remains connected.

But disconnecting the line at the trans is more work... it's a tight fit with a wrench up there. Before you crack a fitting open, clean the area around the fitting first so dirt doesn't drop into the trans.

And one more tip since it's your first time... when you get the old filter off, take a pair of angle cutters (or pliers or a screwdriver or Whatever) to it, and cut the filter apart. Inside is the filter medium, folded in half. Unfold it- and look for large chunks of metal. There might be small pieces... but if you have large piles (like I did), better start saving for a rebuild!