2004 Navigator oil chnage seemed to have affected transmission

Hello I am new to the community. I have a situation that it is so puzzling, I don’t know what to do.
I changed the oil in my car, like I’ve done several times before. Except this time something went very wrong.

  1. I drained the oil and replaced the filter. I waited until there was no oil draining in both areas and the car was leveled.
  2. My car takes 7 quarts, I put 6 and test drove it.
  3. Immediately my car drove sluggish and very different than normal, it felt as to the transmission was not shifting correctly.
  4. I went back home and checked the oil, the dipstick showed my car being overfilled. I drained about a quart of oil and the car still showed over filled
  5. Other than the car running sluggish there is no smoke or any other symptoms of overfilling. I have checked the transmission fluid and it is clear and the oil seems to be only oil.
  6. a few days later the car was still not driving correctly and I drained the entire oil out of the pan. There was only 2.5 quarts than drained. By my estimation there should have been minimum 5 quarts
  7. The dipstick still showed overfilled. I turned the car for a minute and no low pressure light or anything came on
  8. I drove it for 1 block and the transmission wouldn’t shift smoothly especially in reverse
  9. I came back and put the oil back in the car, because I realized for some reason I cannot trust the dipstick.

Any ideas?
thank you in advanced for your kind help

Depending on the kind of car you have, you possibly drained your transmission instead and never drained your oil. Then you put six more quarts in the engine. Check your trans fluid. In my Acura at any rate and Honda, the drain bolts are different and marked but if you are not familiar it could happen and has happened before. Quick check and start over-otherwise its to the shop time.

Based on the description of the symptoms–especially since it followed an “oil change”–I agree with Bing that the OP almost surely drained the transmission, rather than the engine’s crankcase, with the result that the engine wound up with twice as much oil as it should have, and the transmission is now…dry.

An engine can survive a very short period of running while it is overfilled with oil, but transmissions will self-destruct if they are run dry. So, all I can suggest at this point is for the OP to have the vehicle towed (or, probably flat-bedded, in view of the AWD mechanism) to a competent mechanic’s shop for evaluation.

With any luck, the engine will be okay, but unfortunately, I am not optimistic regarding the transmission.

I agree. The answer to the 2.5 qts is that once you fired up & drove, some of the remaining fluid trapped in the pump, torque converter and cooler of the transmission was now in the pan. Your trans is now bone dry.

The engine drained only to the extent of the filter location and then you put 5 qts of oil in on top of what was left so it is severely overfilled.

Most likely scenario that fits the evidence and not the first person to do it…

I agree that it sounds like you drained the tranny and added to the engine.
You’re not the first to make this mistake…

Thank you for your answers. It makes sense except on item 5 I mentioned that I checked the transmission and it was clear, what I meant it was the same red color as it should be and it wasn’t contaminated with oil and was a little low but not by much. When I drained the oil I looked at and smelled it and there was no smell like that of transmission fluid.
I have changed the oil in this car several times and never had a problem. I don’t even know where the plug is to drain the transmission fluid.
My car takes over 15 quarts of transmission fluid. The drain pan I was using is a small 10 quart. It would not have been able to hold the entire transmission fluid. It also didn’t fill up completely. To me it felt like 6 quarts because it was a little over half. Is there any way that the dipstick could be marking the wrong level?
Has anyone else encountered anything similar?
No check engine light has come on, no smoke or anything other than the car running sluggish and the gear not engaging smoothly.

Per your last post I just want to point out that when you drain the transmission you only get about half the fluid out. Most of the rest remains in the torque converter.

I stand corrected. I went back and looked and sure enough. All of you were right and I was wrong.
I drained wrong plug. If I drain and replace the oil to the correct levels and replace my transmission fluid, will that be enough?

Thank you for all your answers

This is an easy mistake to make. Like me for instance. The teenage me was asked by my dad to change the oil in the family car. I’d done this job before on the family’s older manual tranny sedan, but this was a new car I’d never seen the underside before, and it was an automatic, so I accidentally drained the transmission fluid instead … lol … that didn’t go over very well, new car and all, but fortunately I realized there was some kind of problem as the oil dipstick still showed full after the supposed crank-case draining. So the car was never started in that condition, and no harm done.

As long as you didn’t accidentally pour the oil into the transmission, and you didn’t drive far/fast/aggressively with too much crank-case oil or too little transmission fluid, you should be ok by just adjusting both levels to what they should be. Monitor for symptoms and watch for any check-engine-light trouble codes is all.

One note. On some newer vehicles it can be quite a complicated task to refill the transmission, and often involves needing a special scan tool and absolutely level surface to do it correctly. If this applies to your Navigator, best to have the tranny refill done by an expert.

Whatever you do…do not drive this until you replace the tranny fluid to close to the correct level.

You said that you checked the tranny fluid level and it was just a little low. I have a feeling you did not have the engine running like you should when checking the tranny fluid. This would explain how enough fluid pooled in the pan for you to get an almost full reading after draining so much.
As for your tranny holding 15 quarts…mine holds 14 and I only get about 1/3 rd out when I replace the tranny filter and refill it.

If this vehicle…as @GeorgeSanJose mentioned about some vehicles needing special equipment to refill the tranny…is needed, have it towed. You could do major damage to the tranny in a short drive.


A tip of the hat to you for your honesty in admitting your error.
You’ve gotten good advice here as to what to do now. As to checking and correcting the tranny fluid level, read the owner’s manual carefully. Different manufacturers use different protocols, and it’s important to use the correct one.

I wish you the sincere best on this. Hopefully once you get the fluids corrected you’ll have many trouble free miles.

An automatic transmission can suffer damage in seconds due to low or no fluid. The unknown answer to the question is how much damage it did suffer. Top everything up and hope for the best.

If it makes you feel any better, anyone that works on cars has made a mistake or a lot of mistakes.
Even pro mechanics screw up now and then.

I agree with the statements on mistakes. We all make them.

I’d list my mistakes, but I don’t have weeks to be sitting here on the computer.


Hey Guys:

I wanted to thank you again for all your help and to give you an update.
I drained the oil from my engine. It was about double the quantity that it is supposed to have. I added the correct amount back in and I replaced the fluid I had taken from the transmission as well.

after a lot of prayer I started the car and have been driving it for several days and it is running perfectly fine, as smooth as always with no smoke at all and transmission shifting correctly.

I am very thankful for all your help

I’m happy things worked out so well for you. Thanks for posting back. Best of luck.

Sincere thanks for letting us know. We so rarely hear the end results, and it’s great to hear good news.

Based on Godchaser’s experience–as well as my own experience–I am inclined to think that Ford’s automatic transmissions are tougher than many people want to give them credit for.

In my case, I was unable to avoid driving over some rebar that had fallen onto a highway from a passing truck. Because I wasn’t that far from home, and because I heard no unusual noises and didn’t smell anything unusual, I elected to drive the 10 miles or so to my home before checking for damage.

Everything felt normal while I was driving at highway speeds. When I exited, the trans did a very hard downshift on the exit ramp. My house was only about 1/4 mile from the exit, so I drove home. When I got out of the car, I could see a trail of trans fluid on the driveway and a tiny pool of trans fluid then gathered underneath the car. Checking the trans dipstick showed no fluid remaining. Gulp!

Edited to add:
The trans pan had been perforated/penetrated by the rebar that I couldn’t avoid.
It turned out that there were two (or, perhaps three) holes in the trans pan.

The next day, I had it towed to my mechanic, who simply replaced the trans pan & gasket, and refilled it with fluid. The trans shifted normally, and I had no problems at all with the trans for the next 2 years that I owned the car. My car was an '86 Taurus.