Hi All,
Even after replacing both Axle seals, the Pan, and Pan Gasket, my Transmission still leaks gear oil. It only has 89k miles. Where else can it possibly be leaking from? I even checked the reverse light switch and it’s dry. I’m completely dumbfounded by this.
Thank you for the help,
Harris
-Input shaft seal behind flywheel
-Case vent, unlikely unless fluid is overheating or foaming, but not impossible
-Crack in trans case
-Possible leak from clutch slave cylinder
-Shift cable input sliders
Spray the entire case down with brake cleaner. Head over to a local auto part store and grab a A/C system leak finder kit. You will want the kit that has a pair of yellow glasses, and a UV pen light, you will also need a small bottle of the special fluorescent dye mixed with PAG oil, but not refrigerant, the weight of the PAG oil won't matter much.
Add about an ounce to the trans fluid, then drive it. At night, grab the UV pen light and glasses, pop the hood and start looking.
If no UV light leaks are detected, the only remaining culprits would be engine oil, or leaking clutch fluid. Do NOT add the UV dye to the clutch fluid. The light/glasses kit and a small bottle of the UV dye PAG oil should be around $30.
Thank you! Very helpful info. I sure hope its not the input shaft seal as I would hate to remove the transmission. Could you pls point out where the case vent, clutch slave cylinder, and shift cable input sliders are generally located? I know for a fact I havent checked any of those.
I have tried the UV method with little to no success. As far as the actual oil leaking, I’m 95% sure it’s gear oil, as gear oil (as you know) has a distinctive smell.
The clutch slave cyl is in located on the front of the trans, look down to the right of the exhaust manifold, you should see a 3-4" long tube bracketed to the side, it will have a ribbed boot on one end where it attaches to the throwout bearing shaft. It will be one of the more obvious leaks if it is, as the clutch fluid will be running down the forward face of the trans.
The vent tube and cable input slide is actually one "unit" on the top of the trans. Trans vent tubes are always located above the highest point of the case, on manual or auto. The vent is a small, domed black plastic cap, in an Aveo it is actually located on top of the cable input slide. The slide assembly is a square looking aluminum casting with a long cast "finger" on one side, facing forward, the finger is where the slide actually travels, I'm not sure what type of seal is on the shaft, but I do know that unlike an auto box, the trans fluid in a manual isn't really pressurized when operating, the motion of the gears just slings the fluid around inside the case. And yes, used gear oil is a horrible smell, makes my nose flare up just thinking about it!
Here is a crappy pic from a used trans on ebay that shows the vent and cable slide input "box" on top of the trans.
One more possible item:
The differential bearings. When the diff bearings go bad they allow play in the CV axle stubs inserted into the trans, even replacing the axle seals won't solve it, as the amount of motion due to bad bearings can't be hidden by the seals.
Link to a short YT vid: https://m.youtube.com/watch?v=5LZXlCnIQSU
Thank you very much! Extremely helpful. After checking all those components you listed, they all appear to be fine. When I tugged on the CV axles, however, they moved in very much the same manner that the axle did in the video you sent. And granted that I can still see gear oil in the area where the axle seals are, it only makes sense that the bearings are bad. As much as this sucks, I am so glad to atleast find out what the dang issue is! Thank you!! Now, i’m thinking I can remove the trans and take it to a gear shop to have them replace the bearings (if its not outrageously expensive). I’ll call around tomorrow to get quotes. Thanks again for the help!!!!
Glad you were able to verify it!! Not the greatest news, but at least you know!
You are making the right choice on taking it to have the bearings replaced. There are a few used boxes available, but chances are most of them wouldn't be too far behind with the same issue, unless they had extremely low miles.
Let us know what happens, that could be VERY useful info if someone comes up with a similar issue!
I’ve scanned for a few on Ebay and not many look promising. I think the lowest mileage was the same as mine: Right around 86k. Still hard to believe the bearings are showing failure at this mileage. Is there any way I can determine exactly what tranmission is on my 2009? The PDF service manual I have lists a few different ones. Thanks again, will surely keep this thread updated.
You would have to verify fitment by matching the RPO code in the glovebox for the manual trans, and have the seller confirm it, but, most junkyards do not keep that info on hand for used parts, they just list make/model/year, GM is also notorious for having multiple part #'s and revisions for the same thing, and none of the Aveo models were actually built by GM, but by Daewoo further complicating the actual #'s...
However.... I looked at a GM part online site and came up with only ONE :) manual trans for all Aveo/Aveo5/G3/Wave 2005-11:
RPO: Y4M
GM part #: 96957196 @ $1,600.00 (This is a replacement part #, not the same indexing system used for parts on a production line)
So it appears that any manual from a 2005-11 would work, as long as it is for a US/Can car. If the bearings can't be replaced (in my searching I was unable to find service parts for the box itself, only a new unit, I would consult a shop that has verifiable experience with manual boxes before taking it to them), then the lowest mileage box not crying oil out from the seals would be the only option, well beside that fancy new $1,600 unit...
The bearings can be replaced, of this I am sure, finding out what bearing size/type they are and removing the gearsets to access them would be the hardest part. In other words, if you can find a good local shop willing (key word) to do the work, it may be gone for a week or two while they wait on parts. But places like AAMCO/Goodyear service centers will only replace the entire unit, contrary to popular opinion, neither operation rebuilds one single part. They just swap 'em out!
$1600 for a brand new gearbox isn’t as brutal as I would have thought. Yes, my PDF service manual references the Y4M. I’m currently talking to a local gear shop right now that is highly rated and suggested. He gave me a quote so far of 400 something for labor (if I bring the trans to him), and is currently looking up to see if he can get his hands on the bearings. Lets see what he is able to come up with.
Could you send me the link for that transmission at $1600? I will consider that as Plan B if the gear shop isn’t able to get their hands on the differential bearings.
Attachment 12061Sorry about the delay, I'll be back on tomorrow! I had to do brakes on my Roadtrek.
Thank you Houdoxi. I’m now getting ready to remove the transmission from the Aveo. Planning to pick up a transmission jack before starting. Is there anything unique to these Aveo’s when it comes to removing the transmission? It looks like there’s enough clearance down there to move it out without having to tilt the engine, but I guess I’ll know as I get further into it.
Attachment 12066Attachment 12067
Ended up yanking the trans. Will be replacing the Diff bearins later in the coming week. Thanks again for all the help!
I replaced the diff bearings in my 2007 Aveo5. I replaced the clutch somewhere past 300,000 miles. When I did, I replaced all bearings and gaskets. RockAuto.com lists the bearings. I had to pull the third member out of the trans to get to them out. BTW, they where a PITA to get off of the third member. I ended up trying 3 different gearpullers. In the end I used on that I had to cut the tongs down on. I then used a press to press the bearings onto the thirdmember. The races went in pretty easy, just a little tricky to torque down. I didn't have the OEM guage and tool. I just used a large screwdriver and tightened as tight as i could get.Quote:
Originally Posted by Houdoxi71
I find it hard to believe the bearings are bad @ 80k. BTW buy the Redline MT fluid. It is synthetic. Much cheaper than the GM fluid and the trans mission really seemed smoother with it.
Good luck.
Thanks for the note. On the D16 transmission for my 2009 there were 2 differential bearings. The GM bearing puller tool costs $100. I took the differential to a machine shop to have them replaced for much cheaper. I noticed some pitting on the spider gears and will be replacing them as well. I know the mileage is low for bearings, but the transmission is leaking and this is the only thing I havent ruled out yet.
Could you post the link of where to buy that Redline Fluid? Thanks!