johnceggleston Posted June 24, 2010 Share Posted June 24, 2010 (edited) my 97 GT auto w/2.2L swap and 142k miles has a very hard, very hard shift 1-2. much harder than my 95 lego or my 97 outback. i have been reading the endwrench article, http://www.endwrench.com/pdf/drivetrain/Ft4EATTransmissionsW98.pdf, and i'm hoping it is caused by the "dropping resistor". since it is located outside of the trans. does any one know what it looks like, it is supposed to be mounted on the passenger strut tower, but i'd like a some confirmation before i start swapping out parts. if isn't the dropping resistor, it could be the duty A solenoid, failure causes max pressure, or the so called accumulators? they can cause max pressure. does any one have any experience with any of this stuff? if it is the solenoid is swapping the 'valve body' a good solution? any other solutions?? thanks ps: i never drove the car before the swap. Edited June 24, 2010 by johnceggleston Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 24, 2010 Share Posted June 24, 2010 (edited) here's a picture from Josh's page: http://www.main.experiencetherave.com/subaru/images/trannyresistor1.jpg make sure the dropping resistor is plugged in. i actually unplug them sometimes to get firmer shifting and leave them that way for years, but folks will say that makes your transmission blow up, so i don't officially recommend it . maybe yours is unplugged? you *should* have a blinking AT light though if it is. dropping resistors that i've seen are located like you said on the p/s strut tower. it's an aluminum rectangular device, the size *very roughly* of a pack of gum? unfortunately i've never heard of them failing so that seems unlikely as it's just a resistor but of course anything can fail. hope it did or is unplugged. fluid level is good, any AT blinking at start up? Edited June 24, 2010 by grossgary Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted June 24, 2010 Author Share Posted June 24, 2010 fluid level is good, any AT blinking at start up? thanks for the help, i'll check the resistor. no lights blinking and the fluid level is good, but i'm going to change the fluid just for grins. it can't hurt. the trans was replaced with a used one by the previous owner, i i have the paperwork but no mention of the mileage on the 'new' trans and i can't offhand remember when it was done. and during the swap i spent a good bit of time under the car so i know there are no dents in the pan. what i don't know is if a bad duty A would cause hard shifts in all gears? or could dirt / gunk cause a hard shift? time for fluid. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 24, 2010 Share Posted June 24, 2010 i've seen it mentioned before about duty a's causing shift shock - actually i think Skip from here has a really old thread about it? if you have no flashing then the dropping resistor is probably plugged in. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted June 24, 2010 Author Share Posted June 24, 2010 i found skips thread and then found the resistor on my outback, it shifts fine by the way, and i unplugged it. i got a harder shift but not as hard as the GT which is at work right now. i also got the flashing AT TEMP light on the next start up. i doubt the resistor would fail and not deliver a flashing light so it is probably good. but who knows, o2 will give you headaches with out throwing codes. endwrench also said something about the TPS causing a hard shift. any thoughts on this? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 24, 2010 Share Posted June 24, 2010 endwrench also said something about the TPS causing a hard shift. any thoughts on this?yeah that happens and i almost mentioned it earlier. H6 models have a few issues as mentioned in this Subaru TSB: http://www.scoobymods.com/attachment.php?attachmentid=5396&d=1167235017 not your car, but it shows a Subaru TPS failure mode causing shift shock. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted June 24, 2010 Author Share Posted June 24, 2010 if i had an error code of some kind i would at least have starting point, but i have none. no engine codes, no trans codes. if it was a duty a solenoid i would think i'd get a code. on the other hand, it maybe could be an accumulator, maybe. it sounds like they are shock absorbers for the fluid presser, and unlike other auto trans of the 90s these are not spring loaded but fluid pressure loaded. so if one was gunked up or stuck maybe that could cause the problem?? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 25, 2010 Share Posted June 25, 2010 how many miles have you put on it? i hate to suggest it almost since it's that thing we always wish would happen - but maybe it'll "get better"? how bad is it, can you live with it or not really? my H6 OBW has a nice shift shock when downshifting, i just ignore it. put about 40,000 miles now on it. which makes me wonder about trying to fix it now that you bring it up. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted June 25, 2010 Author Share Posted June 25, 2010 how many miles have you put on it? i hate to suggest it almost since it's that thing we always wish would happen - but maybe it'll "get better"? we, my wife has put about 20k miles on it an the last year. it's not a problem for me, because i don't drive it much and she does not complain much, but she started talking about a tribecca recently and i'd don't think i want to spend the money. besides, they pay her $0.50 per mile to drive ~1500 miles for work each month. and i have less than 1500$ in the GT. that's a pretty easy math problem for me. any way, yes we can live with it. if my outback didn't have piston slap she'd be driving that. i swapped the resistors from the outback and the GT this afternoon, no change. Quote Link to comment Share on other sites More sharing options...
eulogious Posted June 25, 2010 Share Posted June 25, 2010 I have the same thing with my 4eat. Hard 1-2 shifts. Gets better when it warms up for me. I have even swap my TCU (modded with different shift maps) and still have it, so I know mine is trans related, not software/electronics related. Maybe something simple like adjusting the brake band might help you? I haven't tried it since I don't have the tool, but I would like too. The FSM says that a hard 1-2 shift could be cause by the brake band. Just a though... Quote Link to comment Share on other sites More sharing options...
bulwnkl Posted June 25, 2010 Share Posted June 25, 2010 (edited) This is an interesting thread. I'd like to share some experience that isn't directly related (not automotive), but perhaps it supports one of the hypotheses offered? Tractor transmissions (agricultural tractors) were normally "power-shift" transmissions for a couple/few decades, until they recently started going to hydrostats, CVTs, etc. The power-shift transmissions use mechanical gears and clutches just like an automotive transmission, but no clutching is required to change gears. These transmission use electro-hydraulic control of the clutch packs to make the shifts for you under full power. Conceptually not unlike an automotive A/T, I suppose, but without the fluid coupling of a torque converter. They refined these transmissions to where the shifts were remarkably smooth. Only the range changes were still very slightly rough. Anyway, my point is that we could always tell when a tractor transmission needed service when the shifting became rough, and some extra noise would attend gear shifts. Range changes would show the roughness first and to the greatest degree (3 gear 'ranges' x 6 gears/range). Re-charging the accumulators would completely eliminate the rough shifting, and all was normal again. The accumulators on the series of tractors we had would slowly lose their nitrogen pressure over time, apparently. Anyway, hopefully this long, rambling account of something not Subaru-related at all can be useful in some way that I can no longer recall. Can you re-charge the accumulators in a 4EAT, or are they 'permanently sealed' units of some kind? Edited June 25, 2010 by bulwnkl Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted June 26, 2010 Author Share Posted June 26, 2010 Can you re-charge the accumulators in a 4EAT, or are they 'permanently sealed' units of some kind? from what i read on the endwrench link, they are pressure charged by the fluid system, if that makes any sense. (i don't even know the right terms.) i say this because they made a point of saying something like 'not springs that can weaken like other transmissions'. my thinking was that one of them is gummed up and not moving as it should or the seal is bad and it's not holding pressure. but i'm not at all sure how it works. Quote Link to comment Share on other sites More sharing options...
bulwnkl Posted June 28, 2010 Share Posted June 28, 2010 (edited) I surely don't know how they work in the Subies, either. Maybe it's not that at all, but they symptoms reminded me of the accumulator issues in the tractors, and when you talked about accumulators, I thought maybe that was the issue? In the tractors, the accumulators are essentially a pressurized cylinder can thingy with a divider or even a bladder inside. Very similar conceptually to how the newer pressure tanks are built for domestic wells, if you're familiar with them? Anyway, one side of the accumulators are charged with nitrogen or compressed air, and the other side sees hydraulic pressure (tractors use a single fluid and sump for transmission and hydraulic fluids/functions). I kinda think the Subie accumulators have to work the same way. If they were just 'cans' that got ATF pumped into them, they couldn't really have any function, since ATF is essentially non-compressible. It's the compressible gas 'on the other side' of the accumulator that allows it to absorb pressure spikes and deliver fluid when/if line pressure drops. I'm sorry that this is only theoretical, and thus not really helpful to you. I just haven't had to have an accumulator charged on a Subie before. Edited June 28, 2010 by bulwnkl Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted June 28, 2010 Author Share Posted June 28, 2010 I'm sorry that this is only theoretical, and thus not really helpful to you. I just haven't had to have an accumulator charged on a Subie before. thanks for th input, it's good to know in theory how it works. piece by piece i'll learn. from some of the pics it looks like the accumulators might be accessable by removing the valve body. but i'm not likely to open up the trans unless i 'know' what is wrong and know how to fix it. even then i'll be very reluctant. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted October 21, 2010 Author Share Posted October 21, 2010 (edited) update: this is my wife's car and until recently i only drive it for short hops to the store or 2m i. commute. but over the last week i have driven it continuously and on a long 3 hour trip. new info: once the trans warms up it shifts just like my other legos, no harder. but when cold first thing in the morning it shifts hard. eulogious mentioned this earlier about his trans. anyone have any insight as to why? would a seal 'warm up' and work better? would a seal that leaks down over night pump up over time, as the trans warms up, and then work better? i guess i should drive it until warm, let sit to drain down for a while but not long enough to cool off the fluid and then drive it again. do they make trans fluid warmers like they do engine oil warmers? Edited October 21, 2010 by johnceggleston Quote Link to comment Share on other sites More sharing options...
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