Should I Replace the Transmission or Fix it?

First of all, I’ve been reading the threads on this forum and you guys are great! I appreciate the time you have taken to help others out. Maybe you can help me decide what to do, as well.

I have a 1997 Lumina with a 4T60E tranny. I stopped at a gas station to get some gas, filled up, and when I took off, the tranny wouldn’t go into second, and the speedometer stopped working. I coasted into a parking lot and found transmission fluid low and leaking, so I had it towed home. I put the car on ramps, and got under it and found a piece of the tail shaft or differential housing (whatever it’s called technically), busted off. The broken piece is about half the size of a baseball and it’s just lying on the sub frame. It’s a piece that had a sensor connected to it too, because a wire is connected to it, which is what stopped the broken piece from just flying out from underneath the car. I have no idea how it happened. I doubt the inside of the tranny blew something out, so I am guessing that a big rock or something just flew up under the car and busted it. However, it looks like a replaceable part and it might even be possible to replace it without pulling the tranny out. I’m willing to put the work in to fix the housing (might even be fun since I haven’t had a reason to work on a car in a while), but I don’t know if it will even be worth it considering the tranny may be shot anyway, since I have no idea how long I drove it like that. Evidently long enough to lose second gear, LOL. It would be worth the trouble if something like that could have caused the computer to shut down all the gears except first and reverse (which I’ve read on this forum has happened), because that’s the only gears the tranny has right now. So now I’m wondering what I should do and looking for some direction. Hey thanks guys! :)

fix it. 4t60e's are a dime a dozen. If the speed sensor isnt in place, the transmission wont shift at all. This is more than likely why you only have 1 forward gear and reverse. I'd buy a case and a rebuild kit and have at it. Big job.

Is the Speedometer connected to the tail shaft? If so then that would make a ton of sense.



The part that is busted is where the drive shaft goes in [bottom left].

http://www.charlietranny.com/4T60E%20WITHOUT%20CONVERTER.JPG



You can see here that it is detachable [Bottom Right]

http://www.charlietranny.com/4T60E%20FIREWALL%20SIDE%20VIEW.JPG

I wonder if a junk yard would let me get one of these off an old transmission, because I can not find where to buy it anywhere. That still leaves the problem of finding a gasket though. I could get an entire rebuild kit, but it seems excessive for just one gasket.

Is the Speedometer connected to the tail shaft? If so then that would make a ton of sense.



The part that is busted is where the drive shaft goes in [bottom left].

http://www.charlietranny.com/4T60E%20WITHOUT%20CONVERTER.JPG



You can see here that it is detachable [Bottom Right]

http://www.charlietranny.com/4T60E%20FIREWALL%20SIDE%20VIEW.JPG

I wonder if a junk yard would let me get one of these off an old transmission, because I can not find where to buy it anywhere. That still leaves the problem of finding a gasket though. I could get an entire rebuild kit, but it seems excessive for just one gasket.

If you can find that piece, change it, as for gasket, wait till you see what is on it now, if its a sealer, use sealer, if its a gasket, see how thick/thin it is and buy gasket material and make a gasket.

I second that. You should be save using a good high temp silicone gasket sealer providing both surfaces are good and clean. I think its chrysler that makes a tranny silicone that actually cures and seals in the presense of atf believe it or not. Maybe look into that is you cant find a gasket.

I would not rebuild it,the 4t60e can be a pain in the butt to rebuild if you do it wrong.My father will not rebuild one of those anymore,one kicked his butt after rebuilding one and now sends the customer down to nearest transmission shop he knows.you do need a special tool to get the c clip off for the final drive and is not cheap,$264.00 for that tool.Do not ever paint over the metal tag.you need some things off that and it tells what the gear ratio is in a shop manual

Okay, you guys talked me into it. I'll get on it in a few weeks and keep you updated. :)

If you didn't drive to far like this, that tranny can be fixed. The reason why your not getting anything other than first is becasue the housing you mention has a speed sensor located on it. If the PCM is not getting any readings from that sensor, it won't shift gears.

The problem you have is that the retaining pin from the final drive cross shaft has broken or come off. The cross shaft starts coming out of the final drive gear and rides on the inside of the housing while your driving down the road, slowly, yet surely carving metal out on the inside of the housing. It eventually cuts the housing in two pieces, the sensor comes off with the outside housing, and the oil in the transmission starts gushing out.

Take the drive axle off, unbolt whats left of the output housing, pull you final gear drive carrier off, replace the retaing pin on the cross shaft, throw the final gear in place again, install a new housing, reinstall everything the way it was, and should be good to go from there.

If you still getting first, chances are, the transmission is alright.

If you didn't drive to far like this, that tranny can be fixed. The reason why your not getting anything other than first is becasue the housing you mention has a speed sensor located on it. If the PCM is not getting any readings from that sensor, it won't shift gears.

The problem you have is that the retaining pin from the final drive cross shaft has broken or come off. The cross shaft starts coming out of the final drive gear and rides on the inside of the housing while your driving down the road, slowly, yet surely carving metal out on the inside of the housing. It eventually cuts the housing in two pieces, the sensor comes off with the outside housing, and the oil in the transmission starts gushing out.

Take the drive axle off, unbolt whats left of the output housing, pull you final gear drive carrier off, replace the retaing pin on the cross shaft, throw the final gear in place again, install a new housing, reinstall everything the way it was, and should be good to go from there.

If you still getting first, chances are, the transmission is alright.

That's awesome! Great detail too. I appreciate your help. :)

Glad to help. Also, I forgot to mention above, when you take the final drive off, carefully note how everything is there. There are shims/bushings thrust bearings, that MUST go in one way only. If this is not done properly, then you will forsure have to be investing in a new tranny, so just be careful when disassembling everything, and your good to go.

Glad to help. Also, I forgot to mention above, when you take the final drive off, carefully note how everything is there. There are shims/bushings thrust bearings, that MUST go in one way only. If this is not done properly, then you will forsure have to be investing in a new tranny, so just be careful when disassembling everything, and your good to go.

Thanks again for your help. The tranny doesn't even hesitate to go into first or reverse so I think you're right and that this can be fixed. I am going to actually get started on it tomorrow. :) I went to the junkyard today and found a 1997 Lumina with the exact same tranny sitting up in the air just perfectly. It was asking me to take the part off right then and there, but they were closing in about an hour and I wanted to look around some more anyway, so I figured I would just make a day out of it tomorrow.

I think you will need a diff to. Those extension housing just don't bust. As for a gasket its a rubber square cut seal you can reuse it if you like as long as its on damaged of course. Diff explosion see this thread: http://www.automotiveforums.com/vbulletin/showthread.php?t=680149

The bushing also wears on the extension housing any tranny shop should be able install one for less than $20

I think you will need a diff to. Those extension housing just don't bust. As for a gasket its a rubber square cut seal you can reuse it if you like as long as its on damaged of course. Diff explosion see this thread: http://www.automotiveforums.com/vbulletin/showthread.php?t=680149

The bushing also wears on the extension housing any tranny shop should be able install one for less than $20

Well that thread was good for a laugh, but I don't think I have the same problem. My internal gears are all okay. The final one is just loose. But it was fun reading that. :iceslolan

make sure the pin is not loose. I would almost bet you have diff problems.

Troy

The retaining pins they use are, in my opinion, not the best choice. It could be better enginered. If you have ever seen one, you'll know exactly what I mean. They get weak, the oil sloshing around makes these pins walk out of the bore and the cross shaft just slips out. I have seen many like this.

From what I gather reading this, it doesn't sound like a diff problem. As for that other example of that guy exploding his gears, at 4000 rpm with one tire slipping on the road the other stationary - what do you expect?

These are tranny mans best/worst types of customers. Best-they will always have work for you, worst-because you will always have them blaming your work as the problem for their trouble.:wink:

I know this is an old thread, but my daughters car just did the same thing...blew the diff housing.

My question is, does the tranny/engine need to be pulled to fix it?


Thanks to You Tube user bah53 for pointing out this forum.

Repairs can be done in the vehicle, but it is obviously not as easy as with a removed unit. Things like exhaust, the cradle, wiring, and others will get in the way.

The right halfshaft will be removed, so the steering knuckle has to be separated from the LCA or strut, meaning the car will have to be supported.