Too much tranny fluid? (1 Viewer)

[80seriesnut]

Is it possible to have too much tranny fluid? My tranny has been shifting a little hard not real bad but I decided to drain and refill. The fluid looked perfect. I got about 4 qts. out but only put 3 back in. The thing shifts perfect. Normally when I would go from P to D you could feel all the gears. Now you cant. Anyways.

 

[Tools R Us]

Is it possible to have too much tranny fluid? My tranny has been shifting a little hard not real bad but I decided to drain and refill. The fluid looked perfect. I got about 4 qts. out but only put 3 back in. The thing shifts perfect. Normally when I would go from P to D you could feel all the gears. Now you cant. Anyways.

Define overfilled? Slightly overfilled should be no issue, greatly overfilled (quarts) will cause it to run hot, sometimes damaging it.

 

[98 SNAKE EATER]

Is it possible to have too much tranny fluid? My tranny has been shifting a little hard not real bad but I decided to drain and refill. The fluid looked perfect. I got about 4 qts. out but only put 3 back in. The thing shifts perfect. Normally when I would go from P to D you could feel all the gears. Now you cant. Anyways.

Did you check it at operating temp while running?

3 quarts is a little low for a typical drain/refill

 

[94SRUNNER]

What did the dip-stick level read?

 

[40TUDE]

yes too much will make it shift hard

 

[80seriesnut]

I checked it about a week ago at operating temp and it was over the hot mark on the dip stick. I dont drive it much but I put about 30 -40 miles on it tonight since the drain and fill. It just shifts better. It seems to me anyways. The next time I drive it (next Tuesday) I will get it up to temp and check it agian. My main question was if it was over full will it make it shift harder?

 

[40TUDE]

as I said previously... yes

 

[1FZFE]

grossly overfilling will cause the creation of bubbles, which could have a decided effect on shifting

 

[Eicca]

I overfilled mine slightly, didn't have any effect (thank goodness)...

 

[PHIL O]

proper way of checking ATF is at working temperature. (after running the engine for about 15 minutes,minimum) have rig parked on level ground and leave the engine running, stick on P. better if you have shifted through all gears manually. correct me if i am wrong mudders

 

[40TUDE]

step 1 is to get it in between the cold lines, this is done by starting it and shifting through all of the gears, putting it in park and checking while still running.

step 2 drive at highway speeds for 15 min and check while vehicle is running, it should now be between the hot lines

hope that was clear enough

 

[ghbyram]

Since this thread is entirely relevant and still reasonably fresh I'll add my scenario here rather than start a new thread.

My '94 (Aug 95 build) is giving similar behavior. I did an exchange yesterday to baseline the ATF from ??? to valvoline max live dex/merc. I got a little out of sorts on the drain and refill quantities but in the end it was between the cold notches while running. Took it for a long 30-40 min test drive to get it hot and was really excited at how smoothly it was shifting compared to before the exchange - felt like I accomplished something for the money, time and mess. When I got back and checked it, the level was right at the base of the twist and well below the hot notches. I ended up adding another 1.5 quarts and am now sitting right between the hot notches. The bad news is it is shifting harder - similar to before the exchange.

I checked to make sure my dipstick tube was well seated to the tranny pan ... there is maybe 3-4 mm of separation which if I adjusted for that error would put me at about the top of the hot zone.

I'm inclined to take a quart out ... what do you guys think? Is my dipstick full of s***?

Grady

 

[S.CarolinaFZJ80]

Tranny fluid should be checked at approx. 180 degrees F operating temperature.

I have a temp gauge installed and it takes 20-30 mins of "stop and go" driving to get it that hot.
It has been my experience that highway driving my does not generate near as much temperature because the clutches are not constantly engaging and generating the heat to required to acurately measure the ATF(hydraulic fluid) quantity. My highway temps are at 140-160 degrees F, consistently.

After you get the correct level dialed in, on your next pan "drain and refill" measure what came out. Replace with the exact same amount. Provided there is no leaks, this should be dead on.

 

[ghbyram]

Not to split hairs but the FSM says 158−176F. I don't have the "normal" Houston commute at the moment so I don't do 20-30 mins of stop and go ever (phew). Even if my temp was a bit low, I can't imagine it had enough temp range left to get me 1.5 qts of additional expansion - but maybe so.

I'm just going to drop a quart and see if the shifting improves. Also like the OP experienced: before I put the additional ATF in it went from P to D gently. Now it goes into gear and loads the chassis pretty heavy when I shift into R & D. About 50 RPM drop for each also. Maybe that's normal I don't know.

Grady

 

[S.CarolinaFZJ80]

I went through the same process as you when trying to find my transmissions optimal level after flushing and refilling since Toyota decided not to provide an exact system capacity.

Before dropping a quart of good fluid from the pan though, drive it around long enough (not hwy cruise speeds) for it to get hot. Contrary to previous posters above, idiling the engine will not get the trans temp up to operating temperature nor will driving it at highway speeds. In my experience, I consistently get 140'ish degres F is norm for flat highways and 160 F is for highways with hills.

It took longer than I expected to get the temps up to operating range by "stop-n-go" driving. I take several readings and average the results of the dip stick level. In my experience 1/4 to 1/2 a quart over or under-filled can make a huge difference in shifting. If you have a suction tube/pump, you may be able to extract it out of the fill tube.

As for the temp, I use approxamately 180 degrees F because by the time i stop on a level surface, cycle through the gears, get out, open the hood & then pull the dipstick, the temp has droped 5 or more degrees F. This temp drop from the fluid running through the coolers while idling in park falls right in line with the FSM temp range you mentioned.

Hope that helps. Good luck getting it sorted out.

 

[CJF]

You guys with hard-shifting issues need to deal with it by adjusting the "kickdown" cable rather than jury-rigging the tranny fluid level.

 

[ghbyram]

I think I have both variables dialed in now. I dropped the quart 2 nights ago but ended up adding about 2/3 quart back in yesterday. Took a 20 minute highway drive followed by 10 on the frontage roads to get some stop and go. Pulled straight into the petrol station, ran through the shifter and took 3 or 4 readings. All were in range.

I had looked at the kickdown initially and my inspection showed it to be at the 1mm spec from the FSM but that is probably spec for a new cable, not one that is 17 years and 178k old. After researching on here a bit more to understand how adjustment should impact behavior, I increased the distance between the boot and stopper slightly - adding a bit more slack at closed throttle -- and that seems to have helped. Shifts are smoother now at the lower gears. Higher gears are very smooth. I may actually tighten it back one turn tonight.

Thanks to all.

 

[Tools R Us]

The cable goes to a progressive system pressure regulator. Your trans is shifted by the ECU, so the cable only effects shift firmness. Adding slack to the cable makes the shifts softer, tightening it make them firmer.

 

[ghbyram]

Yep Kevin ... you're thread from a while back is what helped me understand the adjustment better. Thx.