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kevinrse

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  • Location
    Blacksburg, Virginia
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    Search engine: subaru forums
  • Biography
    PhD student in Civil Engineering
  • Vehicles
    1999 Legacy Outback (30th anniv. edition)

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  1. Gotcha. I got confused by the words "center" and "front" assuming they referred to two different components. Makes more sense now. Since I have done my clutch already, I feel moderately comfortable trying to replace the differential on my own. I'll commence Youtube and Haynes manual research on this matter. Any advice on good source for the replacement part? Ebay? Subaru dealer? Other?
  2. Grossgary thinks it's most likely VLSD---Texan thinks it is probably center diff.... how would I go about testing to determine which one is to blame? Thanks again!
  3. Oops, keep falling behind on replies. Texan - Not sure if my Subie is spindles w/ cone bearings... sorry, I'm bad on all this terminology. Trying to figure out via Google but can't make heads or tails of search results. Grossgary - well, "during" and "after" could mean a couple of different things. It definitely cannot happen "during" a highway trip because it's only during tight, low-speed turns as I said. No shudder whatsoever on straight turns or curves on roads. If I pull off the highway after a couple of hours continuous driving, and I make a very tight turn e.g. in a gas station parking lot while the car is still hot, that's when it happens.
  4. The above reply was for Texan. Thanks Grossgary, here are responses to your questions: 1. are the tires all the same exact size? All tires were installed brand new same time and are same type. 2. are any of the tires significantly different tread depth (new verses bald)? Left front - 0.192" Right front - 0.157" Left rear - 0.262" Right rear - 0.255" Could this be enough to have worn out my diff? 3. different gear ratio front and rear differentials will cause binding... I have no way of knowing this for sure, but I have owned the vehicle from 198k to 230k miles. I haven't done that. This problem only appeared in the last 1k or 2k miles. I have taken it on very long trips before without the TB occurring. 4. the center VLSD could be on it's way out - are you experiencing any binding at all around town on tight turns? or it's ***only*** after highway driving? Nope, it is ONLY after highway driving. It is quite noticeable when it happens, very jerky. Doesn't happen at all driving around town. Loosening 1/4 turn was done only after the bearings were binding---i.e. in response to that issue. Again, it's definitely a separate issue, but I do appreciate the thoughts on that. Trust me, I was fully cognizant that I did not want to undertighten those nuts. ;-) I drove around town for miles, loosening by tiny fractions of a turn, until the issue went away. Anyways, thanks again for this cautionary advice. If details I provided were extraneous, it was only because I thought they might hold some relevance. Sorry for my noob questions. I really appreciate the help you have offered me here and in other threads!
  5. Great, thank you for the advice. Sounds like almost certainly center diff. Is the center diff actively harming my drive train even when i am driving straight? hope i have not risked further damage. There have only been two times that TB has occurred, both after long highway drive, and only on tight turns on flat dry pavement as you said. I'll see if it happens around town here the next couple of days and check with a thermometer. I have been cautious to always use same tires on this vehicle, but it's at 230k and i've only owned it for 30k. I guess it was bound to happen someday. *sigh*... Thanks again Texan. I will report back with progress. Anyone else with ideas much appreciated!!
  6. Hi 1 Lucky Texan. I kept an eye on things after this post and the problem didn't re-emerge again.... until a few days ago. Same thing---long drive on the highway, TB happened at end of trip when I got off the highway. Per others' comments in this thread regarding bearings/axle nuts: A former mechanic friend whose opinion I trust immensely said that yes, "loosening" axle nuts is often necessary to prevent bearings from binding up when they expand. This was consistent with my experience a long time ago---immediately after I repacked my CV joints during clutch replacement, car would shudder after several minutes highway speed. By "loosening" I am talking about torquing to spec (140-150 ft-lbs) and then backing off axle nut by 1/4 turn. This was echoed by my friend, an experienced Advance Auto Parts clerk, and one person elsewhere on this forum. It solved the problem then, and I have not had issues since---so this is a non-issue here. (Furthermore, TB only manifests when making tight turns. If it were bearings it would happen all the time). So, my only question for 1 Lucky Texan is: Is this TB a symptom of some other problem? Or is it simply something that happens when a manual heats up over the course of a long highway drive? Should I be worried? Can I do anything to prevent it?
  7. Hello all, I have posted a lot here recently during two major jobs---replaced my clutch and did front end work, and later replaced timing belt. During these repairs, I also cleaned & re-packed my CV boots, changed transmission fluid (manual), and changed tie rod boots. I mention this since it might be relevant to my brand new problem, described below: I got the thing running again after the timing belt job, and took a victory trip of about 4 hours highway driving today, at the start of a vacation. During the trip I noticed some very minor steering wheel shudder on the interstate. Once I got off the highway and pulled into a gas station, I realized there was a significant vibration/shudder during tight right & left turns at low speeds. Feels like torque bind based on what I've read about it. But, I'm not experienced enough to be sure---perhaps it could be something else. I did some reading and noticed that (if it's torque bind) it could be my center differential viscous coupling. (I sure hope it isn't!) Relevant to this, I should point out that my transmission fluid was changed recently---but this problem didn't occur until AFTER this long trip. (I've heard/read that in old or poorly maintained cars, changing transmission fluid can cause problems). I did check my tire pressure to make sure this isn't being caused by low tire pressure. I've got 35 psi on the left, and 30 and 32 on the right side. I imagine this isn't enough to cause torque bind. Could I be wrong? I know I should have gotten an alignment done after the front end work, but I forgot to get it scheduled before this vacation. I figured it would probably be OK, since I counted threads when I was removing my tie rods and the vehicle isn't "pulling" to one side. I don't know if a slight misalignment could contribute to this. Also, after my clutch job, I experienced some bearing noise after a few minutes of driving. Eventually I discovered that this can occur if axle nuts are over tightened (this prevents bearings from being able to expand when they heat up). I loosened the nuts a bit and the problem went away. Now I am wondering if today's problem could be the result of the bearings being *much* hotter than they are in driving around town (i.e., 4 hours of driving 75mph). Could it be worth loosening the axle nuts? Finally, could the steering wheel shudder be related to the torque binding? Or are they probably unrelated problems? As always, thanks to all the brilliant Subaru experts who have helped me out on this forum. Much obliged :-)
  8. I'll be damned.... just now repeated compression test on cylinders 1 and 3. 210 and 200 PSI!!! I guess I did screw it up somehow the first time around. Only thing I can think of is maybe I forgot to push the throttle in while cranking? Hard to know, it was a couple of days ago.... but I'm not gonna complain. Thanks again everyone for the help. Someday I will be a true Subaru Master.
  9. Yes, it runs the same as it did before the timing belt slipped---but the compression test made me worry that I might have had an underperforming piston for some time. The engine does run fairly smoothly, but there have been occasions since I bought the car when I wasn't sure if I still had full power. So the results of the compression test made me think I discovered the reason. I can re-do compression test. I also spent quite some time worrying about TDC position. E.g. if someone put the mark on the crank pulley in the wrong place or something, that would affect the test. I used compression gauge when turning pulley and looked for compression to begin occurring, then continued turning until mark was lined up with "0" on timing belt cover. So I'm pretty sure I did that right, though not positive. I did notice one thing when turning crank: When I attached compression tester to cylinder 1 (good---210 psi) and approached that cylinder's TDC, pressure bumped up a bit each time I turned the crank, and it remained up. In contrast, when I attached compression tester to cylinder 3 (bad---60psi) and approached TDC, the pressure on the gauge bumped up a bit each time I turned the crank, but also went down again immediately---i.e. the pressure dissipated. This was behavior would seem to be consistent with the bad compression test performance.
  10. Well, I can't say I'm 100% positive of course. But I was very careful. I checked all 5 marks on belt and corresponding sprockets, counted teeth to make extra sure, re-checked marks and re-counted teeth after...etc... Plus---if I installed it off by one tooth, that would affect the action of both cylinder 1 and 3, right? (since they share camshafts). By the way, I forgot to mention it's relatively high mileage, 228,000 miles---I don't know if incidence of ring/cylinder wall wear increases for high-mileage vehicles?
  11. Per a friend's advice I just performed a leakdown test. I give this info in a new thread. If you are interested check it out here. Thanks again for the help y'all!
  12. Thanks as always for the help. Love these forums. On my 1999 Legacy Outback (2.5L DOHC), I recently replaced my timing belt & components after a slipped tooth resulted in poor compression and misfires on cylinders 1 and 3. Before the timing belt replacement I got 90 and 80 psi compression on cylinders 1 and 3, respectively. Now I get 210 and 60 psi respectively. (On cylinders 2 and 4 I got 190 and 180). I detailed this info in this thread. A friend advised a leakdown test next. I put Cylinder 3 in TDC, held it in place with a socket and breaker bar, dialed input pressure up to 75 psi and got 72-73 on the other gauge, i.e. approximately 3-4% leakage. I could hear a quiet hissing through the oil fill cap. 1) Do these numbers seem right---i.e. are the results of my leakdown test consistent with the compression test? Want to make sure I'm doing it right. 2) Assuming it is right, this means I have worn piston rings or cylinder walls, right?
  13. Thank you. What will happen if I keep driving with any of these problems? I.e., can I drive on 3 cylinders for the life of the car with no other consequences, or will it eventually cause bigger problems? I have a friend with a borescope so I will try to borrow it sometime soon.
  14. Legacy EJ25D 2.5L DOHC. Engine began running rough and idling rough a few weeks back, CEL diagnostic codes said cylinder 1 & 3 misfire. Diagnosed with a compression test. Cylinders 1 and 3 were getting 90 and 80 psi respectively. Cylinders 2 and 4 were 190 and 180 respectively. I just put the timing belt back on and re-checked compression on the right side. Cylinder 1 is now getting 210 psi, but Cylinder 3 is only getting 60. (Note---I did this before the engine was all back together, so I didn't idle it beforehand and the compression test was run on a cold engine.) I'm pretty sure I got back the power I was lacking when the timing belt slipped. Just took it for a spin and it feels about the same as I recall it in terms of acceleration. So, it's possible that cylinder has been underperforming for some time... Now that I have the results of a compression test and verified timing is like new again, is there anything further I can do without getting into expensive territory (valve work... piston rings etc.)? This is an old car (228k miles).
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