i'm changing my trans fluid soon and i need advice... the guy at the parts place looked it up, and told me a 700r4 holds 10 quarts of ATF. 10? whats the best way to get the old stuff out? drop the pan? use a long tube to vacuum suck it out thru the dipstick thing? (i'd rather not disturb the gasket if i can help it..) there isn't a plug like the oil pan, is there? will most of the stuff come out of the converter??? help!

 

Some people do a running flush and Jiffy Lube et al do a machine flush.
I personally drop the pan and change the filter. These transmisions are delicate enough. I don't like to take chances.


[Modified by DON M, 3:59 PM 3/1/2002]

 

If you drop the pan aprox. 5 qts.remain in the TQ converter. If you are just changing the fluid and filter this is fine. If you are changing to synthetic ATF you can remove the oil cooler line at the radiator start the engine and pump out the fluid from the TQ converter. The few seconds this takes dose not build up enough heat to do any damage.
C44EVER

 

I'm trying to switch over to synthetic atf in my trans, but am worried about flushing the old fluid out while the trans is running. I might end up burning out the trans due to low fluid level. Any hints/tip would be helpful on changing over to Synthetic ATF.

-Tim

 

--be sure you get the old filter grommet out, its a real PITA to remove if it does not come out with the filter.

--might want to consider an aftermarket pan, comes with a drain plug and you wont make such a mess the next time (if you currently have the stock pan)

 

- Flushing the trans at Jiffy Lube is expensive. I also wonder if it's a bad thing to drive into Jiffy Lube with a hot trans and flush in cold trans fluid....

- Just sitting there idling a cold trans and flushing it via the cooler lines in the driveway is a good but messy method of flushing the entire trans. With the money you save over Jiffy Lube's price, you switch over to synthetic fluid like Mobil1. The good thing is you only have to do this once, after that you can just replace the fluid in the pan once a year and still have plenty fresh fluid.

- The hard part of switching the trans fluid for me is getting the level right. I have found that the GM 4 speed auto trans (both 700R4 and 4L60E) are very sensitive to fluid level. If I put in too much ATF (by maybe 1/2 quart), the trans hangs up on the 3-4 shift at ~80% throttle. This is a big deal to me esp. on the highway.

- I set the fluid level by carefully monitoring how much trans fluid I have added and stop well short of what I estimate the correct amount to be (by ~2 quarts). Then I test drive the car with a little 4 -5 mile test loop with a 3% grade up hill highway stretch. I add fluid by 1/2 quart increments until it's right. When the trans can make that 3-4 shift at 80% throttle without hanging up, then I know the level is just right.

- I switched to the 98 Silvorado trans pan, it has a drain plug and adds about 1 quart of capacity, only drops about 1/2 lower than the stock pan.

BTW, all of this is for my Impala (my vette is an M6), but it's the same trans as the Vette's.

Eric

 

Just my experince, I'm no expert:

I have never pulled the grommet out. I've installed a shift kit, looser TC (twice no less) swapped the filter and fliud countless times, and yet I have the stock grommet from the factory. I was told if the filter fits tight, there's no need to replace it.

BTW, trying to replace the grommet is the number one problem people have when they do a fluid change. I guy I work with (salesguy :crazy: ) who screwed up sooo bad trying to pull that freaking grommet out he ended up rebuilding the trans (don't ask me, he's a salesguy). And the guys at the trans shop told him they almost never need to replace the grommet.

Eric

 

I used a hook from a hook and pick set and the grommet came right
out. They're like dental tools, any parts store should have them

 

I had a set of those "picks" and I broke the tip right off the first time I tried to get out the gromet. :mad I agree with the guy that monitors the amount of fluid he removes very closely. I go one step further and after collecting all the old fluid , I measure it in a separate container and replace that exact amount with new fluid + 1" of new fluid from a quart bottle. There will always be some old fluid that spills on the ground etc. and misses your container. :)

 

I agree with you on leaving the grommet in place. That is what I did on my CE last year. Just run your finger around the inside of it- If it still feels smooth(no cracks, tear, etc.) then install the new filter into the original grommet. I was told they are made of silicone and rarely need replacing. I have been told the grommet is there to keep the filter in place. Since the filter contacts the bottom of the stock pan, I have no worry of it falling away from the valve body.

 

I run a 3/8 plastic tube down the dipstick tube and sphifon out what I can before dropping the pan. This way there is less mess on the floor after im done.

 

fyi.... for the next time you change the fluid. before you reaasb. go to napa and get a drain plug kit. its about $10, and saves a huge mess