2009leggy Posted July 7, 2017 Share Posted July 7, 2017 Hey guys, I new to the forums and actually just made an account today. I have always turned to these forums for help with my subaru, but have never posted because I usually find what I am looking for with a quick search. I'm having a problem that most of you guys have heard of before, and have probably answered before, but my situation seems to be unlike any others. I believe am experiencing a noisy front/center differential, or a torque converter issue, or a 4EAT transmission issue but before you guys start saying here is some background info: Vehicle: 2009 Subaru Legacy 2.5i Base with 4EAT 82,623 miles Car was a totaled salvage title. I bought the car with 48,000 miles off of the Copart auto auction with a very very minor front end collision. The Only damage was to the hood, one fender, front bumper, radiator, AC Condensor, electric fans, one headlight, and the upper radiator support mount. The rebuild was conducted in my uncle's auto body shop, in a professional manner with professional help. He has rebuilt several totalled subarus before. I removed any and all damaged components, and replaced the timing belt, water pump, thermostat, and some pulleys/sprockets while the front end of the car was removed. I conducted a compression test and all cylinders were at 135psi with 1-2 psi of deviation. I also conducted a leak down test for each cylinder and concluded that my valve train was fine. Although there was no frame damage, I had the car taken to a frame shop to have it checked for straightness and everything was fine. I also did a full tuneup (wires, plugs, coils, air filter, PCV valve, fluids changed etc.). The car was then fully rebuilt: did all body work, put it back together, professionally painted in the shop, and had a front end alignment done. It passed the state salvage title inspection and regular inspection with no problems and the car has run beautifully and quiet since the day I put it on the road in November of 2015. Since then, I have always changed my oil with synthetic every 3k miles, and regularly check all fluid levels. The only things I have done to the car since 2015 is a mild exhaust, brand new continentals tires, and new brake pads and rotors. Fast forward to July 2nd 2017. The car has 82,623 miles on it but is still in mint condition. I noticed a very small exhaust leak at the Y-pipe near my rear diff. I jacked up the front of the car to access the bolts at the mid pipe, dropped my exhaust and welded the leak. Put the exhaust back on, and lowered the car. Now this is where it gets interesting. Upon heading home, I was taking a medium speed, midly tight right hand turn and I felt and heard a very minor vibration/mild ticking/knocking/growl from underneath my feet on the drivers side, and it could be felt through the pedals, floor, and steering wheel. Like I said, it was very minor, and if my radio was on I probably wouldnt have noticed it. The noise went away as i continued straight. It wouldnt make the noise when turning left, and it wouldnt make the noise at low speed turns (under 10 mph). It also made this noise upon heavy braking, but not upon light breaking. After about 10 minutes of driving, the noise went away all together and I figured it was nothing to worry about. It has five days since that first incident, and now the noise has come back under slightly stranger circumstances. When letting my car warm up before heading to work, the vibration can be felt and heard at idle, while the car is in park, at about 800-1000 rpm during warm up. After a few minutes, the vibration will go away after the warmup sequence has finished. Then, with the foot on the brake and the car in drive or reverse (under load, becomes louder with AC on) the vibration can be felt and heard, but will temporarily cease as I roll forward. Once again, no noise or vibration as I slowly turn out of my driveway, but as I make my first banked right turn on my road at 30 MPH, there is a clear grinding/vibration/growl from underneath me/in front of the firewall by my feet. No noise whatsoever can be heard when turning left. Upon braking, it can be felt/heard and ceases once the car has almost reached a complete stop. Once the car is stopped, the vibration comes back while I am at the stoplight, with my foot on the break. When I turn right and use the on-ramp to get on the highway, the noise is much more audible, and can be felt more the faster/tighter I take the turn. It gets even weirder. Once I have driven on the highway for about 30-40 minutes, I cannot replicate the sound. High speed right turns or heavy braking will not create the vibration/growl once i have driven for 30+ minutes. The sound just goes away completely! But when I start my car to leave work, I once again get that stupid vibration/growl at idle, and while turning and braking, but by the time I get home it is pretty much gone. This is what I have done to diagnose so far: The CV axles are the factory axles, and have no play in them whatsoever. They do not leak, the boots are in excellent condition, and the axle seals are fine. If I turn my wheel all the way to the right and slowly drive in a tight circle, the axle does not click or pop or grind like a CV axle usually does when it is starting to go. The noise cannot be replicated in a parking lot, only when driving at a decent speed. The alignment is very tight, no play in any suspension components, and the car goes straight down the road if I take my hands off the wheel. Brake pads, rotors, and calipers were all inspected and they are in excellent shape. Upon heavy braking, the car does not pull to either side, it stops straight. The gear oil in the front differential and ATF were both full. They did not smell burnt, look burnt, or look funny in the slightest bit. All heat shields were checked for rattling and all were very tight. All plastic trim and inner fender linings were checked for rattling/rubbing and they were also all very tight. I jacked up the car so all four tires were suspended, and had someone accelerate the car while turning and braking to reproduce the sound while I checked the transmission, differential, and hub assemblies with a stethoscope, and I could not hear/feel any vibration or rattling or growl. Like I said, all fluids were fine and not burnt, so flushing the transmission/differential most likely will not do anything. Drive shaft and U joints are tight, no play at all. There is a big possibility it is a wheel bearing, but that would not explain the vibration while the car is in park or idling. The fact that vibration occurs at idle while the car is warming up leads me to believe the problem lies internally within the power train itself. Correct me if I'm wrong, but I think it is safe to rule out the CV axles, suspension, brakes, heat shield, or plastic trim. Possible causes could be: Front differential (bad pinion gears?), the 4EAT transmission, the torque converter (i've read about people having 'torque bind'), motor mounts, or transmission mounts. The issue can be FELT more than it can be HEARD, so I understand this problem can be very hard to explain to other people, and hard to diagnose when I can only communicate to other subaru enthusiasts via typing. If it helps i will try to post a video, but my exhaust makes it hard to hear the noise through a phone camera. I am very confused as to what this noise is, and whether it is just one of those quirky subaru things, or an actual detrimental problem. I have searched these forums and other forums and have heard hundreds of things that it COULD be, but was never able to find a solution for my specific circumstances. The car has low miles and is never beat on! It is always taken well care of. Any help would be IMMENSELY appreciated because I am totally stumped. Let me know what you guys think! (P.S. sorry for the very long post, but I figured if I documented absolutely everything for you guys, it'd be easier to analyze, diagnose the situation) Link to comment Share on other sites More sharing options...
cseagle08 Posted July 7, 2017 Share Posted July 7, 2017 I'd say motor mounts or trans mount is a possible problem. Even if the heat shields are physically tight it could be coming from them as the internal anti-rattle material breaks down it rattles with the actual pipe. A lot of times especially with the 2.5i it's the exhaust manifold heat shield. I'm like 99% sure that the front & center diffs aren't moving when the car is stopped, so if you're hearing the noise at idle sitting still then it isn't that. Torque converter maybe, but that's pretty low miles for a TC to go bad.... I'm going with exhaust manifold heat shield double check - then maybe the engine/trans mounts. Link to comment Share on other sites More sharing options...
2009leggy Posted July 7, 2017 Author Share Posted July 7, 2017 I'd say motor mounts or trans mount is a possible problem. Even if the heat shields are physically tight it could be coming from them as the internal anti-rattle material breaks down it rattles with the actual pipe. A lot of times especially with the 2.5i it's the exhaust manifold heat shield. I'm like 99% sure that the front & center diffs aren't moving when the car is stopped, so if you're hearing the noise at idle sitting still then it isn't that. Torque converter maybe, but that's pretty low miles for a TC to go bad.... I'm going with exhaust manifold heat shield double check - then maybe the engine/trans mounts. Correct me if this is wrong, but the manifold heat shield you are referring to the one that is directly below the timing belt cover in the picture i attached? I agree that this is a possibility. But the noise I am hearing isn't very audible outside of the car. It can really only be heard through the firewall at the drivers side of the car. Another side note, I had dealt with the heat shield on my catalytic converter a while back, and the noise it created was a very sharp and tin like sound. Like a soda can on top of a subwoofer. This is a much more mechanical sound, almost like it is being muffled by some kind of housing. But thank you for the feedback! I will double check it and report back. I hope its as simple as a heat shield Link to comment Share on other sites More sharing options...
cseagle08 Posted July 7, 2017 Share Posted July 7, 2017 Yes that is it below the timing covers. Link to comment Share on other sites More sharing options...
2009leggy Posted July 7, 2017 Author Share Posted July 7, 2017 Yes that is it below the timing covers. Okay I will check it out when I get home from work. Its tricky because the noise will no longer occur while stopped once the car is warmed up. Once the car is warm, the noise can only be replicated by making a right hand turn at a medium speed. I understand that it could be a heatshield, but that doesn't explain why the noise is made and vibration can be felt only when turning right. Link to comment Share on other sites More sharing options...
2009leggy Posted July 7, 2017 Author Share Posted July 7, 2017 I was able to take a video of the sound while on my lunch break at work. The car is cold, and I put the car in drive with my foot on the brake, and the noise can be heard. The noise cant be heard as much when the car is in park. The loud noises are me shifting the car between Reverse, neutral, and drive. Audio quality isnt that great, but you can kinda get a rough idea of what I am hearing. Link to comment Share on other sites More sharing options...
cseagle08 Posted July 7, 2017 Share Posted July 7, 2017 Okay I will check it out when I get home from work. Its tricky because the noise will no longer occur while stopped once the car is warmed up. Once the car is warm, the noise can only be replicated by making a right hand turn at a medium speed. I understand that it could be a heatshield, but that doesn't explain why the noise is made and vibration can be felt only when turning right. The video even more so sounds like a heat shield to me. When it started making noise on my '09 2.5i it was quite rattle-y, and I mostly felt it in the footwell. The turning right thing is weird, maybe just various forces at work that setup the resonance for it. the whole exhaust is mounted in rubber so turning a certain direction could cause it to flex a certain way. I dunno man. still could be the motor mounts, that definitely could happen only turning one direction as the weight shifts. Link to comment Share on other sites More sharing options...
2009leggy Posted July 7, 2017 Author Share Posted July 7, 2017 The video even more so sounds like a heat shield to me. When it started making noise on my '09 2.5i it was quite rattle-y, and I mostly felt it in the footwell. The turning right thing is weird, maybe just various forces at work that setup the resonance for it. the whole exhaust is mounted in rubber so turning a certain direction could cause it to flex a certain way. I dunno man. still could be the motor mounts, that definitely could happen only turning one direction as the weight shifts. Alright, I will take your advice and check out that heat shield and see what I can find. What did you do to correct that rattling in your heat shield? Link to comment Share on other sites More sharing options...
apexi Posted July 8, 2017 Share Posted July 8, 2017 I didn't hear anything that sounded like heat shield rattle to me, but you must have an aftermarket exhaust on the car? Maybe it's just the video clip, but your exhaust sounds super loud, like you have a leak if it's the factory exhaust. I'm having trouble hearing the sound you're talking about, at what parts of the video is it most noticeable? Link to comment Share on other sites More sharing options...
chucks06LGT Posted July 9, 2017 Share Posted July 9, 2017 Try the transmission mount. I just went thru some similar this weekend after some exhaust work. I felt a knocking on the floor board of the car when it was cold and it would generally go away after the car warmed up. It did seem to get worse on right handed turns, but occasionally would "knock" on a left turn. I just re-read your post and its scary how many of the symptoms your car exhibited mine did as well. I didn't drive the car home from the shop ( my wife did ) but she said the car was really quiet on the ride home. Can you feel this in the floorboards? In my opinion a heatshield rattling wont be that pronounced in the body of the car.... Link to comment Share on other sites More sharing options...
2009leggy Posted July 19, 2017 Author Share Posted July 19, 2017 Try the transmission mount. I just went thru some similar this weekend after some exhaust work. I felt a knocking on the floor board of the car when it was cold and it would generally go away after the car warmed up. It did seem to get worse on right handed turns, but occasionally would "knock" on a left turn. I just re-read your post and its scary how many of the symptoms your car exhibited mine did as well. I didn't drive the car home from the shop ( my wife did ) but she said the car was really quiet on the ride home. Can you feel this in the floorboards? In my opinion a heatshield rattling wont be that pronounced in the body of the car.... Yes it is a very odd noise that I cant explain. The fact that it does it while the car is not moving is what concerns me. I would believe that it was your typical CV joint or wheel bearing if it only did it when I was moving at speed. But this is a little different. Yes I can feel it through the floorboards. It is definetly more pronounced than a heat shield and no noise can be heard under or around the outside of the car. It Can only be heard inside. When you go outside to try and listen for it, it seems that the engine noise is drowning out whatever sound it may be. Thats why it's easier to feel than to hear. I heard it could be piston slap? But thats odd because my car has lowish miles. All motor mounts and transmission mounts are fine. There is no wobble or play in them whatsoever. Im starting to think its a motor issue :confused: Link to comment Share on other sites More sharing options...
2009leggy Posted July 19, 2017 Author Share Posted July 19, 2017 I didn't hear anything that sounded like heat shield rattle to me, but you must have an aftermarket exhaust on the car? Maybe it's just the video clip, but your exhaust sounds super loud, like you have a leak if it's the factory exhaust. I'm having trouble hearing the sound you're talking about, at what parts of the video is it most noticeable? I do have an aftermarket exhaust and it is drones a decent amount, but no leaks or anything, its just loud. What you are listening for is the constant thud/low pitch/bassy sounding knocking that occurs as I shift my car from drive to park. You can hear me moving the gear selector, but after I stop moving the gear selector listen closely with headphones Link to comment Share on other sites More sharing options...
rubasu09 Posted August 16, 2017 Share Posted August 16, 2017 Ever figure out a fix to this problem? I'm experiencing something similar with my '09 2.5i limited, automatic. Many more miles at 208k (got it at 41k), but it's been running great. I had some work done on it this weekend. Rear wheel bearings and front axels. Also had timing belt, thermostat and water pump replaced. I got the car back today and noticed something similar to what you described. The car seems louder, or vibrating more than it usually does when in gear. Most pronounced when not moving. The car is noticeably quieter in park and neutral. The difference isn't normally that drastic. I switched back and forth between drive and reverse a few times and felt the car make what seems to be a more recognizable dip than before as well. Link to comment Share on other sites More sharing options...
apexi Posted August 16, 2017 Share Posted August 16, 2017 Aftermarket cv axles in automatic transmissions can create a vibration when shifted into drive with these cars, most noticeable when the car isn't moving, like at a stop sign. Link to comment Share on other sites More sharing options...
rubasu09 Posted August 17, 2017 Share Posted August 17, 2017 Also noticing that the car has less power when releasing the break but not applying any acceleration. Would that be due after market CV axels? Link to comment Share on other sites More sharing options...
apexi Posted August 17, 2017 Share Posted August 17, 2017 Chances are they disconnected the battery, so part of me thinks the ecu and transmission could be relearning, causing the feeling of less power. Link to comment Share on other sites More sharing options...
rubasu09 Posted August 18, 2017 Share Posted August 18, 2017 Hmmm interesting. I wonder if it will normalize itself. Gas mileage has been about the same through the first tank. Link to comment Share on other sites More sharing options...
1-3-2-4 Posted August 19, 2017 Share Posted August 19, 2017 Chances are they disconnected the battery, so part of me thinks the ecu and transmission could be relearning, causing the feeling of less power. When I had my '08 Tribeca it was horrible after a ECU reset a lot of throttle lag which took maybe about 40-45 miles before it started feeling normal.. Link to comment Share on other sites More sharing options...
2009leggy Posted November 7, 2017 Author Share Posted November 7, 2017 I am beginning to suspect the issue is a motor mount or transmission mount. I visually inspected the motor mounts and they look fine. Is there a good way to test it other than just visually inspecting it? I noticed when idling during warmup (engine stays at about 1500RPM for two minutes or so) the motor seems to vibrate a great deal (from left to right, not front to back, which makes sense). If it happens to be just a motor/transmission mount, is this something I should worry about and try and fix ASAP, or would it be fine to just fix it whenever I get to it? Link to comment Share on other sites More sharing options...
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