I have a '97 Civic with the D16Y7 and MT, and was doing an oil change yesterday. I noticed grease slung on the backside of my engine, and some on the firewall as well. It is directly in line with the inner driver's side CV axle boot. Problem is...the boot looks fine. I spun the wheel slowly by hand to look for tears or rips in the rubber, and I couldn't find anything wrong. The two "hose clamps" seem to be on there tight as well..

I was wondering if the CV axle could fail like this and throw grease, without having an obvious defect? Every one I've seen that's done this has had a ripped or torn boot.

Sorry if this is a stupid question, I had never seen it before. And when I tried Googling it, it just kept coming up with "torn CV" results. Thanks in advance.

 

If you examine the boot very closely I think you'll come to find a small pinhole.

 

That grease is also really persistent. If you (or the previous owner) had a blown boot in the past, and replaced the axle, the grease from the old axle would still be there. Your average drive through undercarriage spray isn't going to get rid of it.

 

Clean the grease off and drive the car norally. Inspect in a week. If there is more grease, then replace the boots.

 

Had a Limited Lifetime from AutoZone, so went ahead and replaced it. I'm under this car regularly to do oil changes, and would have noticed this if it were there last time. Here are two pictures:






Isn't that odd? You can see the perfect circle that the grease was being thrown in.. I cleaned it up with a towel and replaced the CV axle. Just thought it was HIGHLY strange that I couldn't find a rip or tear in the boot, even after I took the boot off.

 

Maybe it's just your camera/flash, but that's the most oddly granulated grease I've ever seen.

 

It does look granulated, but it could be that pinhole theory. If it's small enough for the driver not to notice, I'd be willing to bet the hole only lets out very small amounts of grease, so it'd be tiny drops. Just, accumulated. Am I making sense?

 

Makes sense. I thought it was REAL weird too. Judging by the placement, the spatter, the trajectory.. it HAS to basically be CV axle grease, though, right? I'm not burning oil at a higher rate.. expansion tank / coolant has stayed good (hasn't overheated or anything).. I mean I just drove this thing back from Texas two weeks ago for work, and am about to go out-of-state again. Definitely weird.

 

That's grease, definitely not oil, so yes only the cv boot would be the culprit in that area.

 

Had the same problem, that IS pinhole spatter. The grease usually wont show up by the pinhole either, as it only expands by centrifugal force and pretty much cuts off the grease flow as soon as the cent. forces reduce....by far a very effective sphincter. Congrats, your old axle has an *******.

 

Damnit you *******, I was drinking!

 

Hahahaha ******* laugh riot over here XD

 

I've had boots go bad and start throwing grease from between the boot & CV joint. They weren't torn.....their ability to hold back the grease had simply failed. The grease is heavy & axle spins quite fast. This means the boot's seal must hold back quite a bit of pressure at speed.

I replaced the boots and all was well.

The pinhole thing sounds good too.

Good luck.

 

Did you guys know there is no such thing as a "centrifugal force"? It's actually "Centripetal Acceleration" that causes these effects. This is an EXTREMELY common misconception.

Think of it this way.... When you stomp on the gas, are you pushing your seat backward, or is the seat pushing you forward? Hopefully everyone understand that yes the seat is in fact pushing you forward.

Now apply the same observation to a turn. When you crank the wheel right at speed, are you pushing your seat to the left, or is your seat pushing you to the right?

Centripetal Acceleration.