mtsubie Posted January 31, 2012 Share Posted January 31, 2012 I just had my auto-transmission replaced in my '02 Outback because the diff was screaming like a banshee (and getting worse). The replacement is a used transmission freighted over from Japan with roughly 45k miles on it. Everything seemed normal until I accelerated hard (like getting onto the highway) and then the shift from first to second and second to third included a sudden and severe drop in power for about a second at the most. It felt as though all power to the drive train was gone and then suddenly came back. At first, I thought that maybe this was a quirk I could live with as I don't really drive the car that hard, but after a couple of weeks decided that I had experienced the symptoms more often than expected and that we needed to replace the replacement. The short of it is that the second replacement has been installed and has the exact same symptom. I never experienced this with my old transmission, just the whining differential, so though it would seem that the problem has nothing to do with the transmissions I don't see how that is possible. The mechanic did tell me that the cooling lines did not line up exactly even though he was told by the outfit selling us the transmission that it was an exact match. I believe he mentioned that testing showed that the transmission and rear diff were a good match - my words not his, but I don't think rear diff is the problem. Anybody have any thoughts on this? I've searched and searched the internet and come up empty-handed. Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 31, 2012 Share Posted January 31, 2012 How many miles on the car now? What engine? Look for loose vacuum and breather hoses. When was the last time it got a tune-up with plugs wires filters? Link to comment Share on other sites More sharing options...
mtsubie Posted January 31, 2012 Author Share Posted January 31, 2012 About 122k on the 2.5L engine. I've had it for a little over 2 years and put the last ~33k on it. Not really had a tune up per se, but I have had it in for major servicing including the timing belt service. You think this could have something to do with loose vacuum/breather hoses? Link to comment Share on other sites More sharing options...
Fairtax4me Posted January 31, 2012 Share Posted January 31, 2012 Pulling the transmission out requires quite a few things to be removed. Among other things all of the air box and intake tubing that attaches to the throttle body has to come off to get access to the top of the transmission. There are at least three breather hoses that attach to the air box, any one of those left loose can cause issues. Also check the clamps that hold the air box together at the seam in the middle. On some models there is an air filter in there, others just have a "dummy" filter. Make sure the halves of the box are joined correctly. Vacuum hoses don't typically need to be removed but someone leaning over/on the engine with their hands/elbows, laying tools on top of the intake manifold, could crack or knock loose an old dried up vacuum line somewhere. They should feel soft and pliable, if any feel hard like plastic, that makes them brittle and much more susceptible to cracking. A basic tune-up on these consists of replacing fuel and air filters, PCV valve if it has one. New plugs and wires, NGK or Subaru OE plug wires ONLY on the 2.5. Use the plugs that are recommended in the owners manual. About $100 in parts and it will make it run better and/or prevent future issues. Link to comment Share on other sites More sharing options...
mtsubie Posted January 31, 2012 Author Share Posted January 31, 2012 Thanks for the reply and info. Seeing that the mechanic has now done the transmission R&R on this twice, I would hope he would have caught something like this but if it is a crack it could easily be overlooked. After paying for one used tranny and labor for install twice, I just want a car that will stay on the road another 100k. If anybody else has even heard of symptoms like this, I'd love to hear about it. Symptoms do not manifest with gentle, normal acceleration just with hard acceleration. The hesitation is more abrupt when the tranny is cold but that makes sense to me I guess. I absolutely never experienced anything like this before the original tranny was replaced. Link to comment Share on other sites More sharing options...
nipper Posted January 31, 2012 Share Posted January 31, 2012 What does the tachometer say when this happens Link to comment Share on other sites More sharing options...
mtsubie Posted February 1, 2012 Author Share Posted February 1, 2012 Can't give you numbers (if that's what you're looking for) because my mechanic is hanging onto the car for a couple more days troubleshooting it in his spare time. I can tell you that there isn't a surge in rpms that I recall. Day 1 after the first swap I paid close attention to this and saw no surge whatsoever. Latest data is showing that the torque solenoids for 1st to 2nd and 2nd to 3rd are opening for just a little too long. This definitely coincides with the sudden loss of power during the shift. Link to comment Share on other sites More sharing options...
nipper Posted February 1, 2012 Share Posted February 1, 2012 Ok i'll hang back then for now, did the rpm change at all or hold steady? Link to comment Share on other sites More sharing options...
mtsubie Posted February 1, 2012 Author Share Posted February 1, 2012 It held steady. I will check again when I get the car back in a couple of days. Link to comment Share on other sites More sharing options...
mtsubie Posted February 2, 2012 Author Share Posted February 2, 2012 Problem solved. TCM from a legacy fixed everything, so it looks like we were sold the wrong tranny. Link to comment Share on other sites More sharing options...
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