Transmission Fluid Exchange Writeup (2 Viewers)

[Beowulf]

>> then isn't less risk to the pump to just pull the drain plug and refill a few times? <<

Someone did the math once and I believe it took somewhere around 18 drain/fill cycles to approach 100% new fluid. You get to 80% new pretty quick though.

-B-

 

[Rich]

I do believe that if you were to plug the tranny vent that you could remove both the inlet and outlet hoses from the radiator tranny cooler, extend each as necessary, put the inlet hose into an empty buckect, put the outlet hose down into the bottom of a large clean container of new tranny fluid, and then just by running the engine the old fluid will go into the empty bucket and the new fluid will be forced by atmospheric pressure into the tranny. It would work exactly the same way a vacuum cleaner works. Be sure to leave the tranny dipstick in the tube to keep that sealed off.

You would want to be sure to shift the transmission through all of the gears while doing this, in order to help ensure all of the old fluid is flushed out.

 

[RavenTai]

>> then isn't less risk to the pump to just pull the drain plug and refill a few times? <<

Someone did the math once and I believe it took somewhere around 18 drain/fill cycles to approach 100% new fluid. You get to 80% new pretty quick though.

-B-

yep, somebody on BITOG made a spreadshseet asuming a 16qt capacity and 4.5qt drain that comes out to 5 drains to get 81%, 10 to get 96% and 17 to get 100%

I personally prefer this method, it is cheaper/easier way to ease over to synthetic, also you have continual drains to get rid of accumulated contaminants as 1/4 of it is removed every change

 

[Riley]

So would you do these 5 drains all in one session with a little D/P/R shftiing in-between? OR spread it out over say a couple of months?

 

[RavenTai]

took me about 9 months to go through 5 dino drain/refills, I bought 2 cases of Chevron Dex-III, used a few for the PS flush. changed more often in the begening to baseline the transmission, slower later I was draining/refilling at every oil change, the last dino drain/fill included a pan drop and filter cleaning, when I was out of the dino I started putting in M1, think I am going to move to every other oil change with the synthetic from now on (or 4-5qt about every 10K miles) over time the dino will be replaced with Synthetic, then the old systhetic will slowly be replaced with new


either way gets clean fluid in and the old fluid out, I just prefer this way,

 

[Riley]

Just an FYI - 3/8" I/D hose is required to attach to the top pipe on the AT cooler.

I also found it to be pain in ass to get the old clamp off because the tabs were positioned at the backside near the rad. I had to half remove the AT cooler to get at the clamp. Of course next time it will be easier.

A couple of other comments on the "discharging thru the AT cooler outlet" method:

I found it hard to know how much fluid has been pumped out into the discharge bucket. I didn't want to let the pump get dry and also didn't want to over fill it. With the hose off you also can't (easily) run the motor to check the level. So what I found to work well was to put maybe an extra quart (liter) in and then let it discharge into one of the gallon (4 liter) jugs. Then shut off and replace another jug and then repeat. This approx cycled the level from over of 1 quart to under 2 quarts. The whole process actually me a lot longer than I planned but felt better about it.

R

 

[Rookie2]

I bought 2 cases of Chevron Dex-III, used a few for the PS flush.

Raven,

Where did you get the Chevron ATF? I haven't been able to locate it here.

Thanks,
Rookie2

 

[RavenTai]

its been a wile but I think I got it at BJ's,

 

[Riley]

I've got a couple of questions on ATF ect...

1) Why does the level of ATF vary with the engine being hot? I assume it does because the markings on the dipstick vary depending on temp. Does it expand or something?


2) When ever I read the level it's hard to get a good clean reading. That is when I inspect the dipstick there is about 2" of where the ATF is slightly visible to the eye (a 1/2 width of the blade) and then a point where the ATF covers the entire blade. Which is the correct height to measure to?

Sorry to be so anal about this but I want to make sure it's correct.

 

[RavenTai]

The fluid expands when heated, but not when the engien is up to temp but when the transmission is up to operating temp, it takes much longer to get the transmission up to proper temperature than the engine

The fluid level is often at or above the valve body so there is not much volume per inch of fluid compared to the rest of transmission pan, also there is a lot of fluid in other places in the system as that fluid expands the excess winds up in the pan, that all translates into a very noticeable level change (in inches) with temperature,

The spot where the fluid covers the entire blade is what you want; the stuff on only part of the blade is from residual on the sides of the tube,

Don’t know if this is common but the dipstick had a texture to it that made it hard to read, I polished the end with steel wool (being careful to clean all wool bits off after) and it is easier to read now

 

[Riley]

Thanks Raven, you answered my other question in the process which is getting the transmission up to temp... that's a lot of driving I would think.

 

[RavenTai]

yep, I check it after my 35 mile commute to work and it is higher than after just driving arround town,(not by much) the arround town it a lot higher than just warming it up in the driveway

 

[computerbookstore]

Doing the flush like described here do I drain+refill ATF first from the pan under the car as the first step of the procedure or I don't do the drain+refill at all?

 

[ElJefe]

I have always done it by draining first, then slightly overfil the tranny with about 6 quarts of ATF. Now break the hose at the tranny cooler. Start the truck and while it is sitting there idling, pour new fluid in while the old fluid is pumping out. A nice trick is to use a length of clear vinyl hose between your bucket and the cooler line. You will be able to see exactly where the old fluid ends and the new clean bright red fluid starts in the clear vinyl tube. Shut er down, button er up, and check the fluid level.

FYI... while the truck is sitting idling, slowly going through all of the gears all the way down to 1 and back to Park will get all the old fluid out of the valve body as well.

 

[Cruiser Jimmy]

Know your transmission

Here's a pic of the inlet and outlet of the transmission oil cooling lines. Head of the tranny is to the right, output is to the left.

 

[BROKEROB1]

I just did this with the Redline ATF and, thanks to this thread, things went smooth. I did, however, go through 20 quarts of fluid I was astounded at the difference in color. The old dark fluid (looked almost as dark as 10k mile oil) made me feel like I was accomplishing something
Shifting is noticeably more effecient and smooth. I have had some trouble getting my transmission warm/hot to check the fluid level, as it has been pretty cool in the NE lately and my truck normally sees short around town trips.
I also found that this took longer than expected (2 hrs or so) mainly b/c the new fluid went in fairly slow with the narrow fill opening.
Thanks to all for the helpful hints.

 

[JerseyCruiser]

WORLDPAC Filter kit

I found an awesome aftermarket kit with a new filter and hard rubber gasket. It’s made by WORLDPAC and has an exact copy of the filter and the gasket is so much easier than messing with gasket maker. When you drop the pan with this gasket you won’t have to deal with the trouble of removing the liquid gasket seal which I found to be a PITA! I bought the kit from Napa for about $60.00 and it worked out great with no leaks at all.

George

 

[landtoy80]

My old local Toyota dealer stocked an aftermarket gasket for the tranny.
What is the filter, I thought the filter was just a screen?

 

[JerseyCruiser]

Filter

The filter has a screen inside of it. It's impossible to properly clean it, it is easier to replace it.

George

 

[MikePL]

I have a few questions concerning flushing the tranny.

1. Do I have to drain the pan first, then fill it up and proceed with flushing the tranny through the radiator tube/dipstic? What is the difference between draining first or not draining at all? Removing sludge from the bottom?
2. Which method is 'cleaner', which means that it prevents mixing of new and old ATF. Filling through the radiator hose (and draining through the other rad hose) or filling through the dipstick tube?

I am about to do it tomorrow morning, so I have just an evening left to figure things out.

I really couldn't find any information on where oil enters the pan and where it exits. That would be helpful...