Page updated on 05-21-2018

Overfilled transmission?

09-27-2011, 12:18 AM
Hi guys,

It's been some time.

I tried searching the forum but couldn't find much about it so I just wanted to ask what would the symptoms of an overfilled transmission be. My aunt took her 2000 Windstar (same as mine) to the mechanic and he said the transmission has too much fluid in it.

She complained that the transmission would seem to slip sometimes when downshifting or going over speed bumps and that's why she took it to the mechanic. She wanted to ask me first before letting the guy do any work, I'll be driving to her home during the next days to take a look at it and, if needed, drain some fluid out.

What do you guys think? Can too much tranny fluid cause this?

Thanks in advance,


09-27-2011, 05:52 AM
An overfilled trans can do that and even stranger problems. My question is WHY is it overfull? did soemone add too much? More fluid doesnt just magically get there.

09-27-2011, 05:07 PM
Thanks man I appreciate your input.

She says it all started about 2k miles ago when she had the transmission fluid changed.

I test drove the van in order to see what was wrong and let the fluid reach normal temperature. The shifting was harsh sometimes and downshifting was the worst, gear would suddenly kick in after the revs had gone a bit high. Going over speed bumps would cause slipping too, just like I mentioned in my previous post.

I headed back home and checked the fluid level, it was WAY TOO HIGH!. I drained an entire quart in order to bring the fluid level back to the top of the crosshatched area.

I also took this opportunity to measure the volume delivery of the transmission pump, it took about 30 seconds to pump a quart which I think is within specs.

I finally test drove it to see if there was any improvement and VOILA! everything was back to normal; my aunt was so happy to have her van back to normal.

My only concern was the fluid being a bit discolored but I guess it might be normal as the fluid still smells like new (that same nasty smell of brand new mercon V fluid) and as said before fluid has only 2k miles on it. I have uploaded a picture of a drop of fluid on a napkin.

What do you guys think? Could driving it overfilled for 2k miles have caused any internal damage or is there anything to worry about?.



09-27-2011, 05:33 PM
You are on the right track color-testing the fluid on a clean towel. Do the test again, but first clean the dipstick super well. With the engine off, dip the stick and wipe a sample on the towel. Then clean the dipstick again, and pull a second sample ... this time with engine idling. Put sample on towel alongside the first. Then add a third sample to the cloth straight from a bottle of fresh fluid.

Compare the three samples for color/contamination. If there is a difference between the first two samples, there may be some material floating in fluid ... gathering to the surface when the fluid is quiet.

If all spots are very similar ... all is well.

09-27-2011, 08:02 PM
Thanks 12Ounce I appreciate your help,

I will surely check that ASAP (have to drive to my aunt's again).

If the fluid seems more discolored with the engine off and more uniform at idle, that would indicate there are some particles in the fluid, then what, just live with it until the transmission dies?.

She told me that when she had the fluid changed the guy (she really trusts him) showed her the pan and it looked dirty but clean (quoting the mechanics words meaning there were no debris or metallic pieces inside) and fluid was pretty dark and smelly (not burnt).



09-28-2011, 12:44 PM
If the fluid seems more discolored with the engine off and more uniform at idle, that would indicate there are some particles in the fluid, then what, just live with it until the transmission dies?.


Most of the normal wear particles in a tranny or either steel or friction material off of the clutches. It would be abnormal, but possible, for flotsam to appear ... contamination from a leaky radiator cooler, wrong fluids, etc. The "normal wear" particles are easily washed along through the tranny passages and fall out in the low-flow fluid in the pan. You don't want to see a lot of black friction stuff in pan ... but some is normal. Also normal is a fuzzy build-up of steel particles on the magnet. Was the magnet in place?

You don't want to see chunks of metal ... usually indicating more than normal failure.

Drive it til it drops!

09-28-2011, 08:04 PM
Thanks again man,

I drove to my aunt's this morning and did what you suggested to check the fluid color and I must say that,for me, the fluid looks the same at both idle and before starting the engine; and is definitely lighter than fresh fluid. I've uploaded the pictures, I wrote on each piece of paper towel in order to identify them.

I also showed her some pictures I googled about transmission pans and asked her if she could tell one that looked similar to hers when the mechanic dropped it. This is the one she said looked the same:

Click here ( BV-cwtzlFOT9smm1ft03w)

Is that anything to worry about or is it still considered as normal wear?.

I will be draining a little bit more fluid (about 1/3 of a quart) as today it seemed to be a bit above the top mark, unfortunately today she was in a hurry and didnīt have enough time to do it.

Do you think I should disconnect the negative battery cable and let the PCM relearn the transmission behavior or not?

This is off-topic but I will be doing the Isolator bolt fix on the same windstar, it;s not showing any DTC's but I decided to hook my scanner and saw the LTFT's above 7 and after checking the engine bay I saw some engine oil had spilled between the upper and lower intake manifolds. I already checked prices and the dealer wants 133 dlls for only the 8 isolator bolts and the 6 plenum port gaskets. Autozone has for the entire kit from Droman with the valve cover included for only 100 dlls. What do you guys think, anybody has any good/bad experience with Dorman's Isolator bolt kit? The store offers a limited lifetime warranty on it.

Thanks in advance,


09-29-2011, 07:45 AM
I don't see anything about the smears on the towel to concern oneself with.

The pan tells another story ... But first we need to know, "How many miles since the pan was last cleaned?" If 2000 miles, then get ready for some major problems ... that's a very dirty pan ... indicating a lot of clutch wear! If 75k miles, or more, then its not so bad ... and probably "normal". With that much clutch wear I would say the tranny is in its "autumn years/miles". Remember that 100k - 150k miles of service on one of these trannys is about all one should "expect" ... more miles than that and you are just LUCKY! A number of folks have gotten much less.... a few have gotten more.

Of course, she is guessing .... her tranny pan may not have been that dirty.

Just for reference: With repairs, and fair fluid maintenance, my original Winnie tranny went 216k miles. I now have over 100k miles on the Ford reman replacement ... and the pan is staying very clean ... hardly worth wasting a paper towel on to wipe out. So I consider myself very lucky this time around, and if something doesn't just out-and-out break suddenly, I am expecting 200k miles service without "repairs". I use Mobil1 fluid, and do a 15 qt self-flush approx 50k mile intervals.

09-29-2011, 08:11 AM
Btw, the tranny will relearn on its own ... without the battery cable removal.

I have read of folks having problems with aftermarket bolts ... I would stick with Ford bolts, maybe reuse the gaskets.

09-29-2011, 11:23 PM
Thanks again buddy,

My aunt showed me the receipt of the second to last flush and was 7k miles ago but it clearly states that the shop used MERCON fluid instead of mercon v; so the wrong fluid stayed in for 5k miles, she says the fluid was very dark and stinky (again no burnt smell) and recalls that's very similar to what the pan looked like. She complained and had it flushed again 2k miles ago with the correct fluid (overfilled).

She doesn't drives for too long or too much; those 7k miles are a 15 months use and It's a good thing that she can at least answer these basic questions and has kept the receipts. I really wish I can give her some good news but I guess that's not going to happen, right?.

She complains about a delayed forward gear engagement but says it has been like that since she had the transmission rebuilt.

I drove the van for a while today and feels very strong, I wish mine was like that, it doesn't seems to slip anymore and RPM's are near 2k at 60 MPH which I think is OK; I noticed a little surging (1000-1800 RPM's) on the tachometer only while driving downhill with the foot off the gas pedal; I tried shifting to neutral to see if it persisted but the RPM's would spike over to 2000 and slowly go down to 1500 (still driving downhill). If the problem would be a bad torque converter it should be a constant surge isn't it?. My thoughts are that the vacuum leak must be causing it. There is also some surging at exactly 19MPH every time and doesn't matters which gear is selected, still think it must be the isolator bolts causing it.

About the isolator bolts I will get the ford one's and the 6 port gaskets, I don't want to have to deal with the same problem twice; thanks for letting me know about the dorman's.



09-30-2011, 08:41 AM
The question remains, and you and your aunt may not know the answer .... How may miles "ago" was the pan last clean? Flushing will not clean the pan. The pan is so large that sediment can lay against it and never experience much fluid flow ... even in a "flush" ... so the sediment will remain in the pan until it is dropped and wiped out. This is "by design".

The sediment that was in the pan may have been collecting since manufacture! If the transmission repairs were of the right nature ... the pan possibly has never been dropped and wiped before. ??? Do you have any guesses? Its possible the tranny is now in great shape and the wear particles collected in the pan were of an earlier period. Who knows.


I certainly don't mean to a an alarmist ... we really don't have enough historical information to make a good judgement based on history. If the tranny performs well with no slippage ... I would go with that!

09-30-2011, 10:00 AM
A-ha! Thanks man,

Now I understand what you were talking about. With the mechanics I know around here, it wouldn't surprise me if they had drained and refilled with the same old fluid at the time of the rebuild. That thought never came to my mind until know that you mentioned about the pan.

Well I guess the only thing remaining will be to drive it until it stops! Just like you said ;).

I really appreciate your time and help buddy, when it comes to transmissions I'm in the dark :D. I will surely post anything that could come up (I hope not) in the future.

Best regards,


Add your comment to this topic!