ferp420 Posted October 14, 2017 Share Posted October 14, 2017 Thank I'd like to seem really put that long travel car they built through its paces. Me too it looks like one of my rc cars lol Any idea what in the transmission would cause a gravelly noise while engine braking or coasting down? I dont realy know anything about trasmissions but from the basic discription i would guess dirrty gears the back side dosent get used as much so if it sat for any time there might be deposits on the back side of the gears i would do alot of down shifting and engine breaking try to ride the back side of the gears as much as posable then flush it and add some super gooupy additives and see if it goes away if not its probably a bad bearing but im just guessing Link to comment Share on other sites More sharing options...
pontoontodd Posted October 15, 2017 Author Share Posted October 15, 2017 Me too it looks like one of my rc cars lol I dont realy know anything about trasmissions but from the basic discription i would guess dirrty gears the back side dosent get used as much so if it sat for any time there might be deposits on the back side of the gears i would do alot of down shifting and engine breaking try to ride the back side of the gears as much as posable then flush it and add some super gooupy additives and see if it goes away if not its probably a bad bearing but im just guessing Boy would I be happy with the backside of the gears being dirty and just needing to be run. Sounds like a good explanation! Link to comment Share on other sites More sharing options...
pontoontodd Posted October 15, 2017 Author Share Posted October 15, 2017 Took the Outback to our friend's place and gave him a ride in the woods with the low range. We were both impressed with what it could do. You can creep up pretty steep obstacles at a walking pace. Then I got it high centered, partially because I was trying to go as slow as possible so I had no momentum. Fortunately with the electric jacks and recovery ramps we got off quickly and easily. I got some video but it's probably not very good. By the time I'd gotten out to his place (before offroading) the car was making some intermittent scraping noises, kind of like a brake dust shield rubbing or a dried out worn ball bearing. Definitely load and vehicle speed dependent, mainly makes noise when engine braking or coasting down. Sometimes it will make noise for a minute and then go quiet for a minute. He thought it was something out at the passenger front wheel. He noticed the RF IB CV boot was torn so I replaced that when I got home but didn't see anything out at the wheel rubbing or scraping. By the time I got home it was making some noise even in neutral when the car was stopped. I crawled under and the noise was definitely coming from the trans, not sure if from inside or the throwout bearing. When it does this and you push in the clutch the noise goes away. My wife and I went to central Illinois to go camping this weekend. Weather forecast turned out to be accurate and they had nice weather and it rained at home. Took the kayaks with us and had a good time. The relevant part of this story is that the trans continued to make the scraping noise intermittently, but never when under load, for the ~400 mile trip. The only other noise I noticed was a few times when we got back into town accelerating from a stop it would make a squealing noise, usually in second, kind of like when you first start up some cars and the belts squeal. This trans does have more overdrive than the stock Outback trans, which is nice, drops RPMs to about 3500 at 80mph in fifth. It can still accelerate up a grade into a headwind with the kayaks on the roof so it's not too much overdrive. If anybody else has transmission noise ideas I'd like to hear them. Link to comment Share on other sites More sharing options...
jf1sf5 Posted October 16, 2017 Share Posted October 16, 2017 Any idea what in the transmission would cause a gravelly noise while engine braking or coasting down? Could be the back lash of the front ring and pinion, or not enough/too much preload on the diff bearings Link to comment Share on other sites More sharing options...
Gloyale Posted October 17, 2017 Share Posted October 17, 2017 Any idea what in the transmission would cause a gravelly noise while engine braking or coasting down? Most common failure I see is the upper shaft rear bearing. Pretty easy replacement if you open the trans. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 17, 2017 Author Share Posted October 17, 2017 Most common failure I see is the upper shaft rear bearing. Pretty easy replacement if you open the trans. The one on the rear transfer gears? Or the one on the end of the input shaft? I'm working on taking the tailhousing off. Several people have suggested the rear transfer gears / bearings / rear center diff bearing are most likely to be causing the noise, and I figure I have to pull most of the same parts out of the way to check that in the car, if it's not obviously something back there, the whole trans will come back out. Link to comment Share on other sites More sharing options...
Gloyale Posted October 17, 2017 Share Posted October 17, 2017 I mean the large one at the rear of the input shaft. You will have access to it to check it if you have the transfer section off. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 17, 2017 Author Share Posted October 17, 2017 In the process of getting at the trans I took out the propshaft. Looks like it might have been rubbing a little, but who knows when. Might have been rubbing on the little bracket that bolts to the trans tunnel that holds the shifter brace/pivot so I hammered that up a little. Judging by how much rubbing and scraping I've heard, I think it would look a lot worse if had been the propshaft. This is after I cleaned up the middle. I cleaned up the whole thing and painted it so I can tell if it rubs again. Most of the Subaru trans experts I talked to suggested the noise was probably coming from the rear transfer gears, bearings, or center diff bearing. I took the back of the transmission apart. Didn't see any bearings noticeably sloppy or discolored. I did notice this one has tapered roller bearings for the upper rear shaft and a bolt on bearing for the lower rear shaft. The original trans in this car had normal ball bearings for all three. I probably should have listened to jf1sf5 and played with diff bearing adjustment first. All drive subaroo also said that was the most likely cause of the noise. So that will probably be next. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 17, 2017 Author Share Posted October 17, 2017 I mean the large one at the rear of the input shaft. You will have access to it to check it if you have the transfer section off. You mean the one with the snapring on it? I can see it but I can't see any of the balls or anything to tell if it's failed. Also in these pictures you can see the high/low cable shift in place. Link to comment Share on other sites More sharing options...
Gloyale Posted October 17, 2017 Share Posted October 17, 2017 You mean the one with the snapring on it? I can see it but I can't see any of the balls or anything to tell if it's failed. Also in these pictures you can see the high/low cable shift in place. Grab the tail of that upper shaft and give it a wiggle. It should not move at all. If it does, that's the culprit. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 18, 2017 Author Share Posted October 18, 2017 Upper shaft had no wiggle. I decided to just pull the trans since I had most of the work done with everything disconnected. I think I discovered the source of the noise: I may not have had the pin lined up perfectly with the hole, but I could tell when I had it apart last time that it had been put together and not lined up before. Probably why the pins are pushed flush with the bearing saddles. So now for the fun of disassembling that shaft, replacing the bearing, and trying to set up the front R&P. Anyone know what year/model that bearing should fit? Like I said, the transfer gear bearings are different than the ones in my original 99 trans, so I'm wondering if this one is too. Link to comment Share on other sites More sharing options...
Subaru Scott Posted October 18, 2017 Share Posted October 18, 2017 Yeah man, after something like that, you're gonna need to go over that trans with a magnifying glass, looking for cracks, warping, etc. Manual trannys are pretty forgiving, but there are limits. When I saw you shimming under the nosecone, I knew that box wasn't right. Of course, if it wasn't D/R, I'd say start over. The pinion bearing should be the same as most. My JDM D/R came from a 98 Forester, if that helps. Good luck, leave no stone unturned! Link to comment Share on other sites More sharing options...
pontoontodd Posted October 18, 2017 Author Share Posted October 18, 2017 Since that bearing just rides on the pinion shaft, which is worn about .010" now, I will probably just use a different used ring and pinion out of one of my other transmissions. Anybody know how important it is to really use those pins? I was thinking about just grinding them flush. Either that or I have to pull them out and space them up a bit so I can actually tell if they're lined up with the bearings. Also, I can't seem to find the shifter cross joint on the Subaru dealer site or Rock Auto. I know I've seen them for sale before, I think from the dealer for about $30. The bushings in this one are going out so I'd like to replace that while it's all apart. Link to comment Share on other sites More sharing options...
Gloyale Posted October 18, 2017 Share Posted October 18, 2017 Pins, espescially that one are important. It keeps that bearing from spinning in the case, and keeps it from walking fore/aft where it could interfere with the pinion or the gear set. They should protrude about 2-3 mm above the bearing seat. If you find that a bearing has spun, and the seat in the case is worn/damaged it's a throw away.......or post apocolypse, you can take a slightly blunt point punch, and hammer "dimples" about every 5mm in a zigzag pattern. The edges of the dimples will be raised and provide for the clamping force required to hold the bearings still in the case. similar to knurling a piston. This is particularly important for that large input shaft bearing, as it has no pin to keep it from spinning. Link to comment Share on other sites More sharing options...
Subaru Scott Posted October 19, 2017 Share Posted October 19, 2017 Mark the bearing with a sharpie if that helps, to get it lined up close. Then turn the bearing till you feel it clunk down. I made new bushings for my cross joint with some nylon tubing from the hardware store. You will have to grind off the end of one of the pins to get it out, then drill and tap a hole in the end of the pin to install a small bolt to hold it back in. I did have to ream the ID of the tubing a little with a drill bit to get perfect fit. It's amazing the difference it makes in shifting! Link to comment Share on other sites More sharing options...
pontoontodd Posted October 19, 2017 Author Share Posted October 19, 2017 (edited) Pins, espescially that one are important. It keeps that bearing from spinning in the case, and keeps it from walking fore/aft where it could interfere with the pinion or the gear set. They should protrude about 2-3 mm above the bearing seat. If you find that a bearing has spun, and the seat in the case is worn/damaged it's a throw away.......or post apocolypse, you can take a slightly blunt point punch, and hammer "dimples" about every 5mm in a zigzag pattern. The edges of the dimples will be raised and provide for the clamping force required to hold the bearings still in the case. similar to knurling a piston. This is particularly important for that large input shaft bearing, as it has no pin to keep it from spinning. Good to know. I can't imagine these bearings spinning but OK. These pins were pushed down almost flush. I think I can get them out and shim them up a bit. Edited October 19, 2017 by pontoontodd Link to comment Share on other sites More sharing options...
pontoontodd Posted October 19, 2017 Author Share Posted October 19, 2017 Mark the bearing with a sharpie if that helps, to get it lined up close. Then turn the bearing till you feel it clunk down. I made new bushings for my cross joint with some nylon tubing from the hardware store. You will have to grind off the end of one of the pins to get it out, then drill and tap a hole in the end of the pin to install a small bolt to hold it back in. I did have to ream the ID of the tubing a little with a drill bit to get perfect fit. It's amazing the difference it makes in shifting! I did mark them with a Sharpie but since they were basically pushed down flush there was no feel. I'll get them sticking up a little. I made a bushing for my Impreza and I know what you mean. I just thought if I could get a new cross deal for reasonable it would save me some time, but the dealer wants $70. Next question, the big needle bearing next to that bearing that failed will not fit back in the hollow shaft that holds all the gears. The hollow shaft from the dual range measures a few thousandths smaller than the one from my old trans. Both pinion shafts measure the same and the bearings fit the same. I'm thinking I'll just polish out the hollow shaft, just wondering if it should be a press fit for some reason. I'd really prefer to use the gearstack that was in the dual range since it looks very good and has a little more overdrive in fifth. Link to comment Share on other sites More sharing options...
Gloyale Posted October 19, 2017 Share Posted October 19, 2017 Good to know. I can't imagine these bearings spinning but OK. These pins were pushed down almost flush. I think I can get them out and shim them up a bit. Oh, they spin if there is no pin there. Like old air cooled VW main bearings. don't know why they were so far pushed down. Wonder if someone drilled them deeper to "get them out of the way". It can definately be frustrating to get the bearings on the pins. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 19, 2017 Author Share Posted October 19, 2017 Oh, they spin if there is no pin there. Like old air cooled VW main bearings. don't know why they were so far pushed down. Wonder if someone drilled them deeper to "get them out of the way". It can definately be frustrating to get the bearings on the pins. I'm guessing when it got assembled one time someone didn't line those up and tightened things down, pushing the pins almost flush and leaving marks on the bearing. Probably what cracked the one that broke. I got that hollow shaft polished out so the pinion shaft spins in it, then swapped around the washers on the small end to get the drag called out in the FSM. Next up is R&P mesh, going to try to get it close and then have to wait because I had to order gear paint, no one in town seemed to have it. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 21, 2017 Author Share Posted October 21, 2017 More pictures of the carnage. You can see the flats worn in some of the rollers, at least one of them was sideways when I took it apart, not sure if it was really going around that way while it was together. You can see the wear on the pinion shaft too. You can also see the needle bearing got toasty. Here you can see where some RTV has plugged one of the oil holes. That has to be from my assembly, it was sealed up with gray stuff before and I used red stuff. Gear paint came in, so I checked the R&P mesh this morning. Here is where I started once I had good backlash and preload on the diff bearings: drive side coast side FSM seemed to indicate the pinion needed thicker shims, so I did that and re set the backlash. drive coast Seems pretty good now, if anything maybe it should have more backlash based on the mesh pattern but it is right in the middle of the spec in the FSM at .006". One half adjustment on both diff bearings brings it up to .008", which is over spec. Any experts out there have an opinion? Link to comment Share on other sites More sharing options...
jf1sf5 Posted October 21, 2017 Share Posted October 21, 2017 Gear mesh seems good. Have you already changed all the bearings or just swapped ring and pinion from another gearbox ? Back lash can be verified from the drain plug hole after the gearbox is assembled. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 21, 2017 Author Share Posted October 21, 2017 Gear mesh seems good. Have you already changed all the bearings or just swapped ring and pinion from another gearbox ? Back lash can be verified from the drain plug hole after the gearbox is assembled. Mainly just using ring and pinion from another gearbox. Most of the other bearings seemed good except those I posted. I measured the backlash at .006". Link to comment Share on other sites More sharing options...
jf1sf5 Posted October 21, 2017 Share Posted October 21, 2017 If I remember last time I did it, it was something between 0,12 and 0,18 mm and 0,10 mm preload on the diff bearings. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 23, 2017 Author Share Posted October 23, 2017 I got the pins out of the saddles. Had to weld a piece of metal to the one for the pinion bearing to get it out. Put small pieces of rubber under both to space them up. The one for the pinion bearing is sticking up too high in this picture but you can push it down with your finger so it's only sticking up a little bit. Now I can tell when the pins are lined up with the holes in the bearings. The next problem I ran into was that the ring gear rubbed on the dual range selector ring. In the picture below you can see the dual range ring gear (right) had a chamfer on the outer face. The one out of my old trans (left) did not. So I put it in the lathe and took the angle grinder to it, turned out like this. Dual range original ring gear on the left, modified one on the right. This was the best picture I could get of the clearance issue, high range is the worst case, has some clearance now. So I got the rest of the trans together. A couple of my friends stopped by and we got it in the car and hooked everything up. We drove out to our other friend's woods and tested the dual range again, my friend who usually goes on trips and races with me was impressed with what it could do. Put 60+ miles on it and it's quiet so far, not noticeably leaking, and shifts through all the gears. Link to comment Share on other sites More sharing options...
pontoontodd Posted October 23, 2017 Author Share Posted October 23, 2017 While I had the trans out I did some other things. Put the stock passenger seat back in. Inner tie rods were slightly loose so I replaced those. We set the toe and centered up the steering. Coolant wasn't really 50/50 anymore so I drained that and we put in a new thermostat (old one had holes drilled in it) and fresh 50/50 for the winter. New exhaust manifold gaskets. We fixed the hood latch, the safety catch was hanging up so my friend ground part of the lip off so it didn't catch on that. I turned up a delrin bushing for that shifter u joint, the stock bushings were starting to go. Put in a new throwout bearing. Got the windshield replaced a while ago. While it was out (they brought the wrong one the first time) I tried to seal up the sheetmetal in front of it. This is what that looked like after we pulled the body back together: I just bent it back relatively flat and put RTV on it. Super thin so I don't think welding it would have strengthened the car much and I probably would have just gotten weld spatter in the blower motor. A while ago I'd fabbed up this bracket for the passenger side tablet. The rubber came off the RAM ball mount by the end of the V2R. This one is much stiffer, thinking about doing something more solid like this for the center tablet. I took this picture while the windshield was out. I made the visors before the V2R, helps with glare a little bit. Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now