Transmission replacement?

Dandy. Before you waste any money on something that might not be needed, take the shaft to a Honda mechanic and have them inspect it. Out of 100 cars that leak transmission fluid from a half shaft, 99 are going to have nothing more than a worn seal. Those are about five bucks. The metal parts, including everything with splines, are hardened steel. I've never seen those parts fail, and if there was excessive wear, you would have had some noticeable vibration before this. I'm hoping you're finding a problem where there rally isn't one.

I'd feel better if you had a mechanic look at the parts. There very well could be something wrong there, but until I see it myself, I'm betting you just have a bad seal. If you reach inside the differential to that splined gear, that will move around. There's just the teeth of two mating gears holding it in place while the half shaft is out. You'll see two machined and polished surfaces on the inner cv joint next to its splines. The smaller diameter one rides on a bushing and there will still be some play there between the cv joint and that bushing. The larger diameter surface is where the lip seal rides. That seal is flexible enough to move around and follow the cv joint as it wobbles. If there's leakage there, there's one of two causes. The seal has become dry-rotted and / or hardened from age and heat, and it has cracked, or that bushing has been chewed up. I've never actually run into a chewed-up bushing. There would likely be no damage to the cv joint because that surface is hardened, but the bushing is made of very soft metal and you would feel the roughness, and you'd find a pile of gold metal flakes when you wipe your finger inside. Many bushings have oiling grooves in them. Don't let those fool you into thinking that's damage or wear.

With excessive wobble from a worn bushing, the cv joint can move far enough away from the lip seal to allow it to leak, but you would most likely also feel a vibration at certain speeds. Rotating parts that wobble have a "resonant frequency" they like to vibrate at, just like the pendulum on a grandfather's clock. At anything other than that rotational speed the shaft or joint is less likely to vibrate. Hit that magic speed though and you'll feel it. That much wobble would cause quite a bit of fluid leakage while you were driving, and usually less leakage standing still.

If you can see into the center of the seal. Try to see if here's any cracks in the rubber. If you see any, the rubber is hardened and brittle. Pop a new one in and the leak should stop.

Your pictures didn't load. Other people are having the same problem. I don't know what the answer is, but I think they have to be in. Jpeg form. I used to be able to use Microsoft Word to draw pictures, then copy them to Microsoft Paint and save them as a. Jpeg file in the drop down menu. Maybe that still will work.

Wow. You definitely do have an issue there. Look for a bushing outside of that splined gear that's chewed up. The gear can be loose. It meshes with two other similar gears. Along with the one on the other side, they all rotate inside the differential assembly as a unit. They won't cause a vibration, but that bushing will let the inner cv joint move away from the axle seal too much and cause the leak you found. You might be able to replace that bushing by using a special tool to pull it out once the seal is removed. The new bushing is tapped in but be careful to not twist it or push it in crooked. That can deform it and cause it to rub on the cv joint and fail again. Use a new seal too.

Not sure what issue you're referring to. That bushing is pressed in but to my knowledge, there's no bearing that's pressed in. If you remove the small bolt in the differential that lets the large round pin slide out, that will allow the two axle gears to fall out or be lifted out. That large pin also has two similar gears on it. Those will fall out too. None of those four gears ride on bearings. The outer two do turn with the cv joints, but in relation to the housing they sit in, they only turn a little, and very slowly, when the two front wheels are going at different speeds, (turning a corner).

Not sure what Honda uses in their differentials. U.S. Domestic cars have used a 5/16" head bolt since almost forever. The threads are right under the head of the bolt, then the pin extends about another inch. Sometimes when that large center pin gets hammered out, the pin can shear off. You can often get them out by drilling a small hole next to it so you can reach in with a pick to pry it out. That happens most commonly with manual transmissions because you're on and off the power so often when shifting gears.

I don't see anything obvious there, but it's hard to tell from a picture.

Make sure the motor mounts are good and tight

roy

Yes it could. Did you use a new or used trans?

Roy

I would suggest doing that as a start

Roy