Transmission Fluid Flush or Drain/Fill?

[jay333]

Too much transmission fluid?

I have another (hopefully last) related question to the transmission fluid replacement. Before I begin I checked the transmission fluid via the dipstick. Fortunately, it does look very pink and light in color. Regardless I am going to change it. But I noticed that the current fluid level as indicated on the dipstick seems very high. It is measuring a good inch on the dipstick above the highest 'hot' notch (and the engine is cold). The vehicle is sitting completely level. For those who may be familiar with the dipstick it is measuring up where the dipstick has its second twist (again about an inch above the max hot notch). How problematic is this? Any comments? Is too much transmission fluid a bad thing? Thanks.

 

[xtremewlr]

I have another (hopefully last) related question to the transmission fluid replacement. Before I begin I checked the transmission fluid via the dipstick. Fortunately, it does look very pink and light in color. Regardless I am going to change it. But I noticed that the current fluid level as indicated on the dipstick seems very high. It is measuring a good inch on the dipstick above the highest 'hot' notch (and the engine is cold). The vehicle is sitting completely level. For those who may be familiar with the dipstick it is measuring up where the dipstick has its second twist (again about an inch above the max hot notch). How problematic is this? Any comments? Is too much transmission fluid a bad thing? Thanks.

You check fluid level with the transmission hot (drive around for 5 minutes or so). Have the motor running, shift thru all the gears on the shifter, Park down to L and back, you don't need to drive for that. Put it in park, leave the motor running and then check fluid level.

 

[firebirdguy]

I have another (hopefully last) related question to the transmission fluid replacement. Before I begin I checked the transmission fluid via the dipstick. Fortunately, it does look very pink and light in color. Regardless I am going to change it. But I noticed that the current fluid level as indicated on the dipstick seems very high. It is measuring a good inch on the dipstick above the highest 'hot' notch (and the engine is cold). The vehicle is sitting completely level. For those who may be familiar with the dipstick it is measuring up where the dipstick has its second twist (again about an inch above the max hot notch). How problematic is this? Any comments? Is too much transmission fluid a bad thing? Thanks.

if you are checking it the right way with engine/trans fully warmed up & engine running in park, then yes, an inch over the full hot mark is way too much fluid, & if its cold then its even worse. do a drain & fill to the right level or full flush & check the level when done. id do longer than 5 minute drive, when i check my trans temps with a scan gauge, 5 minutes barely gets it to 100*f, fully hot is closer to 140-150. but either way, yours is too full based on the reading you described.

You check fluid level with the transmission hot (drive around for 5 minutes or so). Have the motor running, shift thru all the gears on the shifter, Park down to L and back, you don't need to drive for that. Put it in park, leave the motor running and then check fluid level.

tgis is the right way to check trans fluid, but id do longer than 5 minute drive from totally cold, when i check my trans temps with a scan gauge, 5 minutes barely gets it to 95-100*f, fully hot is closer to 140-150 that takes ~15 minutes of city driving, highway may be a faster warm up.

 

[bombventure]

Alright, im reviving this old thread instead of starting a new one since it has a ton of good info. Think im gonna pull the trigger and do a simple drain and fill on my 04 (w/dipstick). Admittedly I got scared of all the horror stories of trans flush/drain and fills on high mileage vehicles so I never wanted to do it. As time has gone on Ive got more into DIYing and Ive been doing work on my 4R myself.

Anyways, Im currently at 216k and Ive never touched it. Bought it at 111k. Checked the fluid and its still very pink/red. Im under the assumption it was probably serviced before I bought it at some point if it’s still this color. I think Im still in the clear. Gonna start slow, and see how the first drain and fill goes!

Any tips or advice are always welcome!

Edit/Update: did the drain and fill. The truck is shifting so much better now. 1st to 2nd sometimes felt hard, well thats gone now. Silky smooth. Valvoline Maxlife ATF rocks! Drained just under 4qt and put 4 back in, shifted through all the gears a few times and then took it for a drive to warm everything up. Level on the stick was right on point when I got home. Gonna repeat in another 15k.

 

[razzman1]

If you are doing the flush using the line up at the radiator, do you still need to drain the fluid from the pan first?

 

[Hungryhawk]

I vote for drain and refill. Save fluid that comes out in a clean clear plastic so you can inspect it. Let it settle a few days on a shelf then look for sediment on bottom. If fluid does not seem right or has a strange color/odor-Do another D & R and save in another different clean container. Compare both containers for color and odor.
If you wish to fill thur dipstick tube/pipe, find a clear piece of stiffwall plastic that has ID to fit Over the dipstick pipe/tube. Put a small hose clamp on clear plastic hose where there is a good overlap on the dipstick tube. When ready to fill, jam clear plastic hose onto you repurposed fill tube tll tight (to keep ATF leak minimal). Put a funnel into top of your new fill hose and pour in proper volume.
Take hose off to check with dipstick. If necessary add more ATF.

 

[SurferUK]

If you are doing the flush using the line up at the radiator, do you still need to drain the fluid from the pan first?

From memory, I think you start out with doing that. Then you top it up with fresh, and start the process of using the pump to push the old fluid out 3 or 4 quarts at a time, with the new fluid "behind" it. You know you're done when the new fluid comes out.

I've done this method with the A343E and the A750F. (The older A343E is easier as it has a dipstick)

Personally I don't go for a p*ss and stop after only peeing out a third, so I don't see the point with the drain and fill only but that's just my opinion.

I think all the scare stories of people blowing up their transmissions by using fresh fluid don't pass any logical theory.

What really happened is they changed the fluid, well over-due, because the transmission had a fault/issue that became un-ignorable, then blamed the fluid change when it inevitably let go.

 

[mildeski]

I was thinking of doing the same thing. I have 205k on mine and I dont know when the last time they changed the tranny fluid since i'm not the only owner. Was doing some research and i was seeing that its recommended to do 1/4 at a time.