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Transmission fluid and alternator?

edited November -1 in Repair and Maintenance
I have a 2007 Honda Civic with 79,000 miles on it. Two weeks ago, the regular service light for an oil change came on, along with the code saying I needed a transmission fluid change. I took the car to a local shop (I have recently moved) and they changed the fluid and did the oil change last Thursday. Car drove fine all weekend. Five days later, I was on an extended trip - I had been on the highway about 90 minutes, when the car lost acceleration, the RPMs went way up, and I saw a little steam coming from the front. I immediately pulled off to the side of the road and called AAA. I turned the car back on to run the AC for a few minutes, then turned it off. About ten minutes later, when I tried to turn it on, it faltered (like a dying battery).



So, had it towed to my original dealer in my old hometown, which is where I had been heading. They diagnosed the following



1) alternator needs to be replaced, hence the loss of power



2) the transmission fluid was brown, looked dirty, and smelled burnt. In other words, they don't think it was changed. They also noted that while they didn't see a leak, there appeared to be spilled transmission fluid under the hood.



They want to flush the transmission fluid, although they won't really be able to test how the car drives until they can get the alternator installed (it had to be ordered).



My questions:



1) Could something that the local shop did with the transmission fluid (or didn't do, as the case may be), cause an alternator to fail, or are these two unrelated incidents that just happened to fall together?



2) What else causes an alternator to go, other than age?



3) Is brown and burnt smelling transmission fluid a pretty good indication that the local shop pulled one over on me and didn't change the transmission fluid, or could it have gotten brown and burnt smelling in five days?



I am so sad that my dependable, awesome Honda has suddenly become unreliable in my eyes, since I am in it a good portion of my week. I'm looking for excuses on why it's not the car's fault!

Comments

  • edited July 2010

    Unfortunately, it looks to me like you are ignoring the most significant symptom that you reported, namely, "I saw a little steam coming from the front". Doesn't that sound to you as if the engine was overheating?

    If the engine was indeed overheating, then we have the question of how long the engine (AND the transmission) were subjected to temperatures that were too high. You did not mention the reading on your temperature gauge, so I am assuming that you did not look at that gauge.

    And, then, we have the issue of your next step, namely, "I turned the car back on to run the AC for a few minutes". If the engine was overheating, restarting the engine after only a very brief time was a very big mistake.

    How does the issue of engine overheating relate to the transmission fluid? Simply because you could have "cooked" the fluid by driving the car while the engine was overheating. In addition to possibly having cooked the transmission, significant damage to the engine could have resulted from your actions.


    When you observe steam coming from underneath the hood of the car, and/or if you observe a very high reading on the temperature gauge, the only appropriate thing to do is to pull off the road as soon as you can safely do so, shut down the engine, open the hood, and allow everything to cool down properly--which could be as long as 45 minutes. While the hood is open, you can assess whether there might be a broken radiator hose or a leak.

    In truth, restarting an engine that appeared to be overheating is very unwise and under those circumstances I would recommend having the car towed in order to have the problem resolved prior to retarting and driving the car. Overheating engines do not suddenly cure themselves, and the origin of the problem needs to be found prior to driving the car again.

    As to the alternator, that failure could simply be coincidental. Yes, 3 years/79k is early for alternator failure, but early alternator failure can happen.

    At this point, you need to have the trans fluid changed before operating the car again, but you also need to have a competent mechanic examine the cooling system for the cause of the apparent overheating. He should also perform a compression test in order to determine if you warped the cylinder head as a result of the overheating.

    When was the last time that the coolant was changed? Do you know for sure that there was sufficient coolant in the radiator? What is the maintenance history of this car?

    We really need to know a lot more about your car, but in the meantime, try to remember to never drive (or restart) a car that gives evidence of overheating.
  • edited July 2010
    Thanks for the detailed response. I should add that the temperature gauge did not indicate any signs of overheating (although we are experiencing record highs in the region this week and the outside temperature was close to 100...). I've had a radiator break on me in a previous car and I'm always on the lookout for that. The steam that I thought I saw coming from the hood was not significant - as in, I thought I saw a wisp, but when I pulled over (this all happened within about 20 seconds) there was no sign of steam or burning smell or any other indication of problem. The car was towed - I wasn't about to drive it anywhere.

    But what I think I am understanding is that as soon as the alternator arrives and is installed, and when the transmission fluid is changed, the mechanic should also give the cooling system an examination? I've performed all the required service on the car over the past three years. I have to go back to my records and double-check the last time the coolant was changed.

    The dealer also told me my air filter was dirty and that I need a new air conditioner filter. Up until the failure on Monday, the car appeared to be driving fine/cooling fine/all systems under control. I checked out fine with my state inspection in April, although I don't think they check things like the cooling system.
  • edited July 2010
    Without being able to actually inspect the car it is really hard to say what is going on. The loss of accel & revving sounds more likely related to burned trans fluid rather than the alternator. The alternator may be coincidental? What warning lights did you get on your dash when this happened?

    My only guess on the transmission would be that maybe the shop overfilled the trans. The overfilling whipped the fluid into foam, the foam failed to lubricate & cool sufficiently, the fluid overheated & burned, and your trans went south (hence the loss of accel & engine revving). The bit of smoke/steam you saw may have been trans fluid that had been forced out of the dipstick - thus the report of trans fluid under the hood & the smoke. If the shop hadn't changed it at all it might be brownish. The smelling burned part really only comes from overheating.

    So its all hard to say - at the very least I'd talk to the actual person at the dealership who inspected the car and try to get their best explanation as to what happened.
  • edited July 2010
    Was your coolant filled to the normal level? If you had adequate coolant and it never showed overheating on the temp gauge, your engine should be just fine.

    The "steam" from the front probably wasn't coolant, it was probably the spilled tranny fluid that reached a temperature where it could combust. Tranny fluid, which is oil, can burn easily if it gets on or near the exhaust manifold. This will create smoke that you can see.

    Sounds like this "local shop" really did a lousy job. I wonder if they used a transmission fluid that's not compatible with Hondas. Honda requires a special kind of transmission fluid. Find out what they put in your transmission.

    When your car lost acceleration and RPMs went up, sounds like your transmission was slipping. Not good. Could be from the wrong fluid. Or overfilled fluid that gets aereted.

    If they ruined your tranny, their insurance company should buy you a new one. Document everything that happened and what they did. Get an inspection from a good independent mechanic. You may have to pursue the "local shop" through the legal system if they screwed up.
  • edited July 2010
    I will reluctantly agree with the opinion that the private shop very likely over filled the transmission. If over filled the transmission may operate perfectly well until the temperature expands the fluid enough that the fluid level rises and becomes whipped into foam by the planetaries and subsequently begins to lose pressure causing the clutches to slip and the temperature to skyrocket. This condition will also cause the frothed fluid to blow out the transmission vent. But even if I had inspected the car at the scene when it failed it would be impossible to be certain of the cause and effect of the situation.
  • edited July 2010
    Thanks all! So, the car is ready, and the dealer mechanic says the car drives fine and the transmission does not appear damaged ( he said there would be pieces of metal in the fluid and transmission if there had been damage?). Since they think it drives okay I guess my best is to drive it myself and be more hyper aware than usual to changes in how it drives. Any advice on what to look for? Before there were no signs until the exact moment of failure....
  • edited July 2010
    Double check the level of the transmission fluid yourself - do this any time you have anyone change any fluids. Some people are incompetent. Others make mistakes. The fall out can be catastrophic. So check your trans fluid yourself. Make sure it it nice and red and doesn't smell burned.

    Ask them if they changed the filter and did a full fluid exchange. That is what I would do.
  • edited July 2010
    I wouldn't be surprised if the wisp of steam you saw was transmission fluid cooking off, but that doesn't mean you should ignore what VDC said. It's certainly possible you have a cooling system failure, as well as a failure of the engine temperature sensor that's supposed to tell the gauge when it's too hot.

    I have difficulty believing that the alternator was the cause of your loss of power. If the RPM's went way up, the power went down, and the transmission fluid was burned, then you may well have a cooked clutch. In fact if the previous mechanic was incompetent enough it's possible that he stupidly somehow got transmission fluid into the clutch, and now it's lubricating the clutch friction plate (which is not supposed to be lubricated) which is causing it to slip, which is heating it up. If that's the case, you're in for a new clutch.

    If the alternator died, your car would continue operating as normal because the battery would power the car. If the alternator died, and you ran the car long enough to drain the battery, then you wouldn't have been able to restart it to turn the AC on.

    The new mechanic's explanation for what made the car do what it did simply doesn't make sense. I'd make sure that what you wrote here is really what he meant to tell you, and if it is, find another mechanic.

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