Hank Roberts Posted June 28, 2005 Author Share Posted June 28, 2005 The bang sounds like bind between the front and rear axles, caused by tire rotational differences. Miles point about matched tires is very important. Naru's suggestion on checking the rotational difference sounds very practical. Normally, as long as you are on a loose surface, bind isn't much of an issue unless either diff ratios are mismatched or tire diameters are mismatched. By rock-crawler, I was thinking of the folks amongst us that do not dodge those 3' boulders but go OVER them. To some of them, a few percentage points of difference in a low gear or intermediate gear might be important, especially as magnified by additional transfer cases and such. Umm... your car had a dual range and CCR sent you a single-range? Anyway check your tires for matched type/manufacturer, size, and wear. And try naru's rotational test. CCR sent a turbo manual 5-speed dual range (weeks ago, they took it back when it didn't fit). I have a non-turbo vehicle. The splines had the wrong number of teeth as noted above. It did not fit into the vehicle, was never used, jmust noticed byt he mechanic and returned to CCR. ALL FOUR TIRES ARE THE SAME SIZE (185s - the size too big to fit under the hood) and are, or were, the same wear level-- before this last week on the road. Now the rear tires are noticeably scalloped /cupped out and feathered (edges of rubber extend over the grooves) after the extra wear of slipping all the time. I'll buy four new tires, but want the transmission fixed first or I'll just destroy another set. Going over a three foot boulder can't be much different than going up a ten or twelve percent slope in the lowest possible four wheel drive -- some of the erosion cuts in the road I use are a couple of feet deep, so it'd be easy to drop a wheel into one and high-center the vehicle. I think the effect on the transmission is probably comparable, considering I may have five people and a load of equipment in the car while climbing or descending these. I'm sure I"m noticing the same small percentage difference anyone would putting full use on the system. I'm starting to understand how a mismatch, for someone using the 42d only for ski trips on snow and ice, might not be noticeable. Thanks Naru for the post about how to test the rotation. I'll take that to the mechanic tomorrow. I mean today. Losing sleep over this stuff, bleah. The mechanic will only test it on the lift -- in Berkieley there are only a couple blocks of gravel/dirt road accessible, a ways away from the garage -- do you think the same chalk mark technique will show the same difference if all four wheels are up in the air? I had thought of asking the mechanic to do that, but didn't know if it would show the rotational difference. Many thanks for the exact Subaru part number. Major warning to anyone with a 1987 California GL, I wonder what that was about. Mine is a 1988 California GL, as far as I know. Gulp. Now I'm going to have to question the exact year it was built, how do I make sure of that? Vehicle ID number, I suppose. Link to comment Share on other sites More sharing options...
LPGsuperchargedBrumby Posted June 28, 2005 Share Posted June 28, 2005 that sounds the same as what happened when i got a replacement 'box that had the 3.9 ratio in it when my rear diff was 3.7...i was told that the new box was 3.7 as well..gotta love(some) JY lunch eaters except i knew something was wrong within a couple of seconds of engaging 4wd ( far to much time driving crusty old Landrovers that torque bind to the max on sealed roads) same problems and 'thump' when coming out of 4wd Link to comment Share on other sites More sharing options...
naru Posted June 28, 2005 Share Posted June 28, 2005 -- do you think the same chalk mark technique will show the same difference if all four wheels are up in the air? Yes,but w/the wheels in the air, the diffs will allow side to side rotational differences that may confuse the issue. Link to comment Share on other sites More sharing options...
Hank Roberts Posted June 28, 2005 Author Share Posted June 28, 2005 -- do you think the same chalk mark technique will show the same difference if all four wheels are up in the air? Yes,but w/the wheels in the air, the diffs will allow side to side rotational differences that may confuse the issue. I'll push them to try the test on the lift, AND to drive over to the one short block of dirt/gravel nearby and chalk-mark it on the ground. Is the math on this -- with "3.70" in the front and "3.90" in the rear, the difference between the chalk mark angles should be about the difference between those numbers, so about 2/37ths of a revolution on each turn? The front wheels will turn, say, 370 degrees as the rear turn 390 degrees? So after ten turns, 200 degrees' difference, the chalk marks should be back to where they started on the front wheels, and should have gone about another half turn on the back wheels? Or am I mathematically a dunderhead here? I know the shop isn't going to be able to understand this math. But -- I guess that's the only way to tell! --------------- I've already chewed up the rear tires considerably -- we did drive maybe fifty or sixty miles of dirt/gravel road in 4wd low range first gear, last week, all steep and nasty. What scares me is -- maybe I'm making the symptom go away by grinding the rear wheels down! If so I'll have to put on new tires just to demonstrate for sure that there's a problem. ------ Any way, at all, to identify a transmission when the serial number tag is unreadable? Or could any case contain any gear ratio, off the "Used Japanese" inventory anyhow? I guess even knowing an unused transmission's serial number wouldn't help -- I gather there's no list of what serial number is what specific transmission, unless Subaru keeps track internally. Link to comment Share on other sites More sharing options...
NorthWet Posted June 28, 2005 Share Posted June 28, 2005 Turbo D/R tranny... sounds like they sent you an RX tranny... REALLY odd. Are you nearer UCB and Montclaire, or Emeryville/Bay? Used to be gravel/dirt lots out along the frontage road near the Bay. Should still be gravel/dirt lots in the parks in the hills. Its been a decade.5 since I stomped around there, so maybe it has changed. I haven't run through the math, but your basic reasoning sounds good. Chalk marks are on the tires, right? Any significant difference between mark angles after 5-10 revolutions would indicate a mismatch. as naru mentions, the open-diffs wil likely confuse things if in the air. Regarding tires, one of my cars had 4 tires that were all nominally 185/70-13s, but they were different brands F-to-R. In heavy rain (wipers having trouble even on full blast), I switched it into 4WD at freeway speed and nearly slid off of the pavement due to the bind. Bind from minor mismatch shouldn't be so noticeable on loose surface, though. Link to comment Share on other sites More sharing options...
Hank Roberts Posted June 29, 2005 Author Share Posted June 29, 2005 Turbo D/R tranny... sounds like they sent you an RX tranny... REALLY odd. Are you nearer UCB and Montclaire, or Emeryville/Bay? I haven't run through the math, but your basic reasoning sounds good. Chalk marks are on the tires, right? Any significant difference between mark angles after 5-10 revolutions would indicate a mismatch. as naru mentions, the open-diffs wil likely confuse things if in the air. Regarding tires, one of my cars had 4 tires that were all nominally 185/70-13s, but they were different brands F-to-R. In heavy rain (wipers having trouble even on full blast), I switched it into 4WD at freeway speed and nearly slid off of the pavement due to the bind. Bind from minor mismatch shouldn't be so noticeable on loose surface, though. TYPE: It's not a turbo transmission this time 'round -- that was first try, weeks ago, from CCR. This is the third try -- electrically matches but gears don't. I'll believe an RX, I have no way to tell. (Apparently the suppliers also can't tell them apart on the inventory shelf, nor can the mechanic, just by looking -- all they can do is identify the turbo spline count, but can't tell the other non-turbo transmissions apart by looking at the outsides. Eeeeeeuggghhhhh! TEST TRACK: We checked and there's still two blocks of dirt road along the railroad tracks just south of Ashby, I think it would be 7th Street -- there was another 4wd vehicle there also testing its shifting when we went. We confirmed the difficulty getting out of 4wd persists. And it popped out of first gear one of the times I did shift from 4wd to 2wd, when the lurch/bang happened as the lever finally moved. Rats. The mechanic was out, the owner was sleeping, 'call tomorrow' says the mechanic's front office. And she was the only person in the place who DID know where it was possible to test the shifter. I asked her to make sure the mechanic knows (sigh). TIRES: All exactly the same size and brand. I suspect that while there's a mismatch in the transmission, the rear pair will keep wearing out fast on dirt/gravel -- but I haven't figured out if that will make things worse, or better. Obviously with proper gearing matches, the tires have to match. But with a mismatch betwen front and rear -- I'm not sure which is turning faster. Well, we'll go get the chalk out and find out later today or tomorrow morning. Arrrrrrrgh. Besides, I also just noticed I have an inch of water inside the bottom of the rear light plastic, noticed it with the backup lights lit, there's this _sloshing_ in there. Gotta take that apart too. But that's for a different thread, don't get me sidetracked, I say to myself .... Link to comment Share on other sites More sharing options...
Hank Roberts Posted June 29, 2005 Author Share Posted June 29, 2005 Nothing sure yet, the news thus far today Tested the transmission on Berkeley dirt road. Definitely binding from 4 to 2wd. And it started popping out of first gear. So this one goes back to wherever the mechanic bought it and he's looking for a replacement still. Mechanic at SOS Subaru now said he "took all the numbers off the original transmission and has found one in Sacramento, used, with exactly the same numbers." And he hopes this one will be right. I'm going to try to get the numbers from him and post them, whatever he's using, see if it makes sense. I tried calling around -- Rising Sun in Chico says, these transmissions now are so scarce they can't rebuild them nor find them. No hope there. Anyone else know of a place that can rebuild transmissions, or that can guarantee supplying the 1988 GL manual 5-speed dual low 4wd replacement? Meanwhile, we're just chewing hell out of the tires and hoping they don't wear out before we get the right transmission in. What else might I break, with a mismatched ratio? Am I likely to destroy the back differential, break an axle or break the driveshaft? Or does it just feel that way when it goes "bang-clunk!" coming out of 4wd? Maybe I just need to carry a bucket of mud and slick up the dirt road under the tires, when I am ready to switch out of 4wd, so the wheels spin easier? Link to comment Share on other sites More sharing options...
NorthWet Posted June 30, 2005 Share Posted June 30, 2005 Honestly, I am surprised that it has been such an ordeal to find the right transmission. If I had to watch some mechanic do all of this I would go nuts. Yes, the binding of mismatched diff ratios (if that is what this) can cause all sorts of damage. I happen to have two 88 D/R 5-speeds, but distance and pre-allocation makes them unuseful for you. They are not that uncommon, especially around here, and I can't comprehend why it is such a problem for folks to find one for you. Good luck. Link to comment Share on other sites More sharing options...
Hank Roberts Posted June 30, 2005 Author Share Posted June 30, 2005 Do you just know their history personally? Or do you have some way of looking at a transmission and being able to tell what it is set up to be used in? My guess is, as long as you know personally what something is, or know the people you're dealing with personally, it's not too hard to keep track. But that here, -- buying off someone's inventory shelf -- picked by people who probably don't know what they have very accurately, or care -- where most drivers would only switch to 4wd when on snow or ice, say driving to Tahoe, and likely never notice or complain about a mismatch .... Someone like me, who uses 4wd a third of the time I'm driving the car, and on mountain roads, is going to be a lot more sensitive to having a wrong gear ratio than most people Heck, the local mechanic claims not to have known there was a grinding-into-second technical service bulletin and fix as of early 1989 for this kind of transmission (tried fixing the second one we got with different gear oil, til I showed him the TSB, and since it threw bad computer codes anyway, sent that one back). And -- I didn't know myself before I got into this mess that there was a TSB for popping out of first gear. It might have been an easy repair, if anyone had read the TSBs and known what they were doing. An old hang gliding buddy owns a trahsmission exchange up in N. Ca., and recognized this problem exactly when I descrcibed it today -- but his old partner who knew how to rebuild Subaru transmissions is long gone, nobody else he knows actually does them nowadays, here. I lived in Seattle from 1970-75 -- there were a LOT more Subarus around and more dirt/gravel road drivers so probably better info about what transmissions are on the shelves, even today. Link to comment Share on other sites More sharing options...
Hank Roberts Posted July 1, 2005 Author Share Posted July 1, 2005 Cross-posting, because this is important info: CCR did respond, and I believe they're right that my mechanic screwed up and ordered the wrong transmission from them, some weeks back. See their post here: http://www.ultimatesubaru.org/forum/showthread.php?t=33119 Everything they've said matches the situation as I saw it at the SOS Subaru garage; it seems the mechanic there was telling me the truth --- when he said his dime store reading glasses weren't good enough. He's mis-read or mis-transcribed part numbers twice that I know of, for the rear differential and the transmission itself, and no wonder he's getting the wrong parts. Link to comment Share on other sites More sharing options...
NorthWet Posted July 1, 2005 Share Posted July 1, 2005 Regarding the final drive ratio in your transmission: I do not know the actual numbers, but I would guess that 95% of Dual-Range 5-speeds have the ratio that is correct for your car. The only car to my knowledge that had a different ratio and had a D/R was the RX, and they are uncommon. Further, the RX was a kind of car that asked to be driven hard, so their transmissions almost certainly wore out at a higher rate than the ones in the everyday soobs. (They were a pregenitor of the current WRX, which are commonly found wrapped around stationary objects near the side of the road.) I am personally unaware of any wiring differences, but it is possible/probable between carb'd and SPFI'd versions. It still should not be that hard for a mechanic to find the right one, and every JDM importer with whom I have dealt over 25 years knew their stock VERY well. As far as possible drivetrain damage caused by driving with mismatched ratios (have you determined this to be the case yet?), I would suspect the the transmission will take the worst abuse (the rear transfer gears and/or bearings), followed by the axle joints, with the rear diff being my last worry. The rumble could also be caused by the damaged tires. Link to comment Share on other sites More sharing options...
Hank Roberts Posted July 1, 2005 Author Share Posted July 1, 2005 Thanks, good reminder the rumble could be the tires. I decided not to take the car back into the mountains this week with the mismatched tranny, despite the mechanic's assuring me it was not a problem. They're putting in transmission number four late today or next Tuesday, and this one was, for the first time, ordered using the Subaru part number they got off the original transmission (confirmed by someone here at USMB). So, I'll just be hoping for another week, then know something. I don't know if the rear power train was damaged -- I did tell the mechanic to look into it for metal chips and change the lubricant. He also said he didn't think it could be damaged and I'll hope you're right. Link to comment Share on other sites More sharing options...
NorthWet Posted July 1, 2005 Share Posted July 1, 2005 I doubt that you will find chips. The thing I would be concerned about (just from my Datsun experience... same diff) is too much strain on the bearings, particularly the side bearings that support the ring/diff-carrier/stub-axles. These can growl quite a bit if abused, but they can also be changed fairly easily. I found it easier just to replace the diff in my Datsun. Off-roaders/rock-crawlers talk about snapped stub-axles more than blown up ring-and-pinions. Link to comment Share on other sites More sharing options...
Hank Roberts Posted July 2, 2005 Author Share Posted July 2, 2005 I doubt that you will find chips. The thing I would be concerned about (just from my Datsun experience... same diff) is too much strain on the bearings, particularly the side bearings that support the ring/diff-carrier/stub-axles. These can growl quite a bit if abused, but they can also be changed fairly easily. I found it easier just to replace the diff in my Datsun. Off-roaders/rock-crawlers talk about snapped stub-axles more than blown up ring-and-pinions. Well, I'm glad I didn't take it back to abuse it more over the weekend. (Can I be a rock crawler if I never get it out of low-range-first-gear 4wd? Maybe a junior creepie-crawler ...) This weekend I go set up insect traps on the mountain, and mail what I catch to the Santa Barbara Beetle Survey .... Link to comment Share on other sites More sharing options...
Hank Roberts Posted July 18, 2005 Author Share Posted July 18, 2005 The fourth transmission replacement is now in the car. It's the first one that actually matches the part number -- all but the last two letters, which I have read several places don't matter. The local shop (finally) wrote down the number they found on the transmission that was originally in my car (the one that had started popping out of first and third gears) -- TW75F9A2... and found one of those, in Sacramento, and got it in last week. I just drove it 30 miles, from Berkeley through the hills of Tilden Park to Orinda and back. It popped out of first gear, three times, first in Orinda (on a city street, as I let it roll toward a stop sign in first gear using engine braking) and then twice more on the road downhill from the crest at Tilden going back into Berkeley, again while using engine braking. Same symptom. Dang. Supposedly that was the last available used Japanes transmission this side of Sacramento with that part number on it. Anyone got pointers to another? I'm trying to contact CCR again, about rebuilding the original one, which is here in the back of the Subaru. Brakes don't feel fixed either. Discouraging three months of Subaru ownership, I start to wonder how y'all stand this. It gets better? ------ Meanwhile -- when you posted the actual correct Subaru transmission part number, I'd taken it in the next day, and the mechanic told me that day they'd actually found the number on the transmission I originally had come in with (made me wonder if they read here, but apparently it was coincidence). Now that their first replacement found matching that number is also popping out I searched the web, and found a match in only one place --- rsgear.com -- makes bearings, and lists this among a huge list of part numbers. ..... BK406 85-90 TY75F 5spd 4x4 D/R 1800 BK407 85-90 TW75F9 5spd 4x4 D/R 1800 .... The second is the one that matches what was posted earlier. The exact number, on the original transmission for my car: TW75F9A2BV (for the non-turbo 5-speed 4wd dual range). My speculation is the "TY" is for the Turbo, but I'm only guessing that. Link to comment Share on other sites More sharing options...
Chewy_719 Posted February 15, 2017 Share Posted February 15, 2017 I just picked up a transmission with the SN:TW75F9A2BV. Is this a good or bad transmission? Link to comment Share on other sites More sharing options...
GeneralDisorder Posted February 15, 2017 Share Posted February 15, 2017 I just picked up a transmission with the SN:TW75F9A2BV. Is this a good or bad transmission? Did you ask to see its report card? Did it do its chores? Maybe you should talk to its mom. Zombie thread. Shoot it in the face! GD Link to comment Share on other sites More sharing options...
BEECHBM69 Posted February 15, 2017 Share Posted February 15, 2017 Did you ask to see its report card? Did it do its chores? Maybe you should talk to its mom. Zombie thread. Shoot it in the face! GD I must be sick in the head because I actually learned something about second gear grinding, from a 12 year old thread....... Dan Link to comment Share on other sites More sharing options...
Chewy_719 Posted February 15, 2017 Share Posted February 15, 2017 Did you ask to see its report card? Did it do its chores? Maybe you should talk to its mom. Zombie thread. Shoot it in the face! GD Link to comment Share on other sites More sharing options...
Chewy_719 Posted February 15, 2017 Share Posted February 15, 2017 That's cute????. I got the trans from a junk yard. And are there any issues that I should know of Link to comment Share on other sites More sharing options...
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