Chocoholic005 Posted November 4, 2020 Share Posted November 4, 2020 I cannot for the life of me figure out anything wrong, so hopefully someone else can point me in the right direction. Some background: During my rebuild, I swapped the 5 speed out for a JDM Spec B 6 speed, Spec B flywheel and clutch masters FX100 clutch kit. I drove this for 1500 miles with no noticeable bellhousing rattle. During this time, the new to me transmission went out and needed to be rebuilt. Rallispec did a full rebuild. I replaced the clutchmasters throw-out bearing with a new subaru part as it was damaged during removal, and reinstalled the transmission. Now, from what sounds like the bellhousing area I have a light, consistently inconsistent rattle; almost like a rock getting kicked around every now and again. This occurs with the vehicle in neutral and the clutch pedal released. Once I get past the clutch engagement threshold, the rattle stops completely. I've pulled the transmission and clutch assembly. Everything looks fine, I'm not seeing any damage or misinstalled parts. I'd very much like to fix this for my own sanity. Thoughts? Link to comment Share on other sites More sharing options...
ViscousSquirrel Posted November 4, 2020 Share Posted November 4, 2020 (edited) It's the throwout bearing. You are describing exactly what a throwout bearing rattle sounds like. Edited November 4, 2020 by ViscousSquirrel Link to comment Share on other sites More sharing options...
blackobxt Posted November 4, 2020 Share Posted November 4, 2020 Mine does the same thing, but mine is one of the springs in the clutch disk. It’s annoying and people love to tell me about it but it doesn’t warrant a clutch replacement at the moment. If you still have it apart, grab the disk and shake it and try to rattle the springs around. Link to comment Share on other sites More sharing options...
Chocoholic005 Posted November 4, 2020 Author Share Posted November 4, 2020 It's the throwout bearing. You are describing exactly what a throwout bearing rattle sounds like. Which is the only thing I can think of given the symptoms... but how do I fix it? Throw out bearings are pretty dumb parts on a complexity scale. Considering it's literally brand new, I don't want to keep buying new TOBs and spending 8+ hours doing a trans R&R until I get a quiet one. Mine does the same thing, but mine is one of the springs in the clutch disk. It’s annoying and people love to tell me about it but it doesn’t warrant a clutch replacement at the moment. If you still have it apart, grab the disk and shake it and try to rattle the springs around. Yeah; I tried that one already. No rattle from the springs. Link to comment Share on other sites More sharing options...
blackobxt Posted November 5, 2020 Share Posted November 5, 2020 Is the tob securely clipping to the release fork? Is the release fork securely clipping into its place? Link to comment Share on other sites More sharing options...
Chocoholic005 Posted November 5, 2020 Author Share Posted November 5, 2020 Is the tob securely clipping to the release fork? Is the release fork securely clipping into its place? You're talking about a 5-speed setup. The 6-speed has no clips and the fork pivots on a shaft rather than a ball. Link to comment Share on other sites More sharing options...
blackobxt Posted November 5, 2020 Share Posted November 5, 2020 Touché Link to comment Share on other sites More sharing options...
Chocoholic005 Posted November 6, 2020 Author Share Posted November 6, 2020 My instinct says buy a new TOB directly from clutchmasters (not OEM Subaru) since that part seemed to be fine to start. But I have no confidence that will actually fix the issue. Link to comment Share on other sites More sharing options...
ViscousSquirrel Posted November 7, 2020 Share Posted November 7, 2020 In all honesty you have a pretty good idea what the issue is. You either drive it like that or you replace it and that decision can't be made for you by anyone on the forums. You may want to climb under it and shake the exhaust and make sure you're not hearing a heatshield just to make you feel better about your decision. Link to comment Share on other sites More sharing options...
Chocoholic005 Posted November 7, 2020 Author Share Posted November 7, 2020 In all honesty you have a pretty good idea what the issue is. You either drive it like that or you replace it and that decision can't be made for you by anyone on the forums. You may want to climb under it and shake the exhaust and make sure you're not hearing a heatshield just to make you feel better about your decision. But it's a brand new bearing, direct from a subaru dealership. It rattled from the second I started the car up after installing the transmission. Unless Subaru is selling out of spec or faulty parts, throwing in a new bearing may not do anything. As an engineer, throwing parts at a problem and hoping you fix an issue is the exact wrong way to do things. And that doesn't even consider all the time I waste pulling the transmission over and over again. Obviously I'm not the first person to have this issue; is everyone just driving around like this? I've read many posts about TOB rattle but literally never seen someone outline how to fix it or what's wrong. I have a bearing on order from clutchmasters as a last resort, but I'd really like to be more confident that's going to fix the issue. Link to comment Share on other sites More sharing options...
ViscousSquirrel Posted November 8, 2020 Share Posted November 8, 2020 (edited) I can’t tell you how many new parts I have bought that were out of spec or non functional. Again. No one on here can tell you what YOU should do with your time an money. As a business person I look at from an opportunity cost and a risk perspective. If the bearing is bad and you drive it until it explodes what are the possible risks and costs associated with that? A tow, a ruined input shaft etc. look up project management risk analysis tools if you’re unfamiliar with how to do that assessment. What’s the time and cost to pull it all apart and check the spec on the bearing you purchased. Subaru doesn’t build that part. That part is outsourced to a 3rd party vendor. That vendor WILL have manufacturer defects. This is what warranties are for. Those are internal defect numbers so I couldn’t tell you what they are and I’m not in product development. Pretending that you can’t get a bad part is naive. The challenger exploded from a bad quality management process in a Vendor that made a seal. The engineer in you that says don’t throw parts at a problem is half right. If you have a problem and replacing every part in the system is cheaper in labor than the diagnostic cost to find the actual problem, what do you do? If you’re running into down time and you have loss of use what’s that worth to you? Personally I like doing my own work and I would have spent the time you have been sitting on it pulling everything apart and checking both the work and the parts. But again, there’s no loss to me there because I don’t mind doing the work. I also have several cars so the down time is meaningless to me. At the end of the day it’s your decision but any decision is better than no decision. Paralysis through analysis. Edited November 9, 2020 by ViscousSquirrel Link to comment Share on other sites More sharing options...
Chocoholic005 Posted November 9, 2020 Author Share Posted November 9, 2020 Personally I like doing my own work and I would have spent the time you have been sitting on it pulling everything apart and checking both the work and the parts. But again, there’s no loss to me there because I don’t mind doing the work. I also have several cars so the down time is meaningless to me. At the end of the day it’s your decision but any decision is better than no decision. Paralysis through analysis. I understand you may have skimmed my thread for whatever reason, as is your right, but please don't make assumptions without reading fully. I clearly said I pulled the transmission in the first post, it's still not in the vehicle as I await a new TOB. I am an engineer for a major OEM, so I understand the part sourcing and quality process. I also know that the likelihood of a bearing being so far out of spec. to cause a rattle vs. being silent is relatively low. This chance is further reduced when I compared the new Subaru bearing to the original Clutchmaster's bearing, and found both to be dimensionally similar. The clutchmaster's bearing spun a little more freely, but I wouldn't think that would cause an inconsistent rattle. Replacing every part in the system clearly wouldn't be cheaper as that would include the clutch and the newly rebuilt transmission. Since, with it disassembled, I cannot find anything wrong, I came to the forum to ask for help; has anyone experienced the same thing? Does anyone know how to fix the issue? etc. Just driving with an unknown rattle that could destroy a $5000 transmission is insanity. Link to comment Share on other sites More sharing options...
ViscousSquirrel Posted November 9, 2020 Share Posted November 9, 2020 A B test with a new throwbout bearing. Report back with the results of the test. People have had this problem and they have commented. You seem to refuse to believe that it could be the throwout bearing. Perhaps it was an installation error. Link to comment Share on other sites More sharing options...
Chocoholic005 Posted November 10, 2020 Author Share Posted November 10, 2020 People have had this problem and they have commented. You seem to refuse to believe that it could be the throwout bearing. Perhaps it was an installation error. I won't deny it could be a TOB issue; but what specifically about the TOB is the issue? The installation? The bearing in relation to the fork? The bearing in relation to the clutch? Something internal to the bearing? No one has told me what the issue is or how to fix it. If people are having this problem and fixing it, no one has spoken up about it. Could it be misinstallation? Sure, but I installed it the same way I did the first time, so maybe unlikely? Open to feedback if someone experienced this due to misinstallation. At the moment, I have no other option but to install the new bearing when it arrives. If this fixes the issue, great! But it could also tell me nothing, and I've lost 8 hours of my life doing another transmission R&R. I'd like to avoid that if possible, so if anyone has feedback on a rattling TOB or alike, please let me know. Link to comment Share on other sites More sharing options...
Max Capacity Posted November 10, 2020 Share Posted November 10, 2020 No feed back other than I trust you did the install correctly, after all you've done to this car...I doubt you did something that simple, wrong. I seem to remember a few years back, I swapped TOB'ings before I installed one because I didn't like the way it felt. I guess you will very OCD about the new TOB. To give you some more insight into not all new parts are great. In July I replaced the OEM Prop Shaft that I replaced a few years back, because the rear U joint was not smooth. That new OEM one had 80,000 miles on it. The one that came in the car lasted 215,000 miles. 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
ViscousSquirrel Posted November 10, 2020 Share Posted November 10, 2020 (edited) https://www.knowyourparts.com/technical-resources/drive-train/diagnosing-clutch-bearing-bushing-noise/ My understanding of the rattle would be that The noise would be caused by the bearing to race clearance. So as the bearing wears down they begin to rattle. That said, all that’s happening is that the tolerances are out of spec from abrasive wear. So it stands to reason that if the race or the bearings don’t meet tolerance specs from the factory then it will rattle like a worn bearing. Edited November 10, 2020 by ViscousSquirrel Link to comment Share on other sites More sharing options...
Chocoholic005 Posted December 7, 2020 Author Share Posted December 7, 2020 Obviously been a while; I actually got the trans installed right before the week of thanksgiving, but then I was out of town. Regardless, with the new (ClutchMasters supplied) throw out bearing, it still rattles, though admittedly less than before. Also seems to be somewhat intermittent; at one point I touched the shifter and it went away until I started the car next, but that phenomenon hasn't been replicated since. I'm at a loss at this point. Link to comment Share on other sites More sharing options...
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