CV Axle report and question. - PeachParts Mercedes-Benz Forum

cirrusman · #1 01-18-2011, 04:30 PM

I rebooted my axles a couple of months ago, put grease in them and went on my way. A a couple of weeks after that my drivers side axle had the clickety-clackettys so I replaced it with a newly rebooted (great job by vstech) axle. A week after that the pass. side started to do likewise. This time, by someone's suggestion in this forum, I decided to just put gear oil in it (I used Lucas gear oil) first before going for the more expensive option of replacing the other side. It worked just fine, the horrible noises (which my wife could hear from her car driving behind me) stopped and the car is running like on butter. Before I tried this, a mechanic suggested that I should replace the whole axle because that noise was metal against metal and it showed metal wear, but I tried the oil anyways.
So, the report is that so far, the gear oil works just fine (it's been a couple of weeks so far) and I'd recommend anyone to try this first if you have good boots but a bad noise.
The question is, how come a little gear oil fixed it? Has anyone worked on an axle before and knows why the oil caused the horrible sounds to stop? And how come the axle grease that I had put in didn't?

Just curious

Diesel911 · #2 01-18-2011, 07:03 PM

Quote:

Originally Posted by cirrusman

I rebooted my axles a couple of months ago, put grease in them and went on my way. A a couple of weeks after that my drivers side axle had the clickety-clackettys so I replaced it with a newly rebooted (great job by vstech) axle. A week after that the pass. side started to do likewise. This time, by someone's suggestion in this forum, I decided to just put gear oil in it (I used Lucas gear oil) first before going for the more expensive option of replacing the other side. It worked just fine, the horrible noises (which my wife could hear from her car driving behind me) stopped and the car is running like on butter. Before I tried this, a mechanic suggested that I should replace the whole axle because that noise was metal against metal and it showed metal wear, but I tried the oil anyways.
So, the report is that so far, the gear oil works just fine (it's been a couple of weeks so far) and I'd recommend anyone to try this first if you have good boots but a bad noise.
The question is, how come a little gear oil fixed it? Has anyone worked on an axle before and knows why the oil caused the horrible sounds to stop? And how come the axle grease that I had put in didn't?

Just curious

Those People who would only use Oil will be saying that they were made for to use Oil so Oil fixed the problem.

However, somepeople have used Grease with no issues.

I am going to make a guess that there was not enough Grease in the right places. And, it would be hard to Grease the Joint properly with the "Cans" still on and the Cone shaped end of the "Can" still attached.
Below are some pics from a thread on another forum. I had to Photo Shop some of them to lighten them up as some were very dark.

But, you can see that the rebuilder went through a great effort to insure there was adequate Grease. He, did everthing but pack the Boots with Grease.
Grease comes in some of the Boot kits sold by parts places.

cirrusman · #3 01-18-2011, 07:54 PM

That's very possible... I poured the whole contents of the little bags that came with the axles but I didn't get to give it a good greasing like you show in these pics... I get it now, thanks!

barry123400 · #4 01-18-2011, 07:56 PM

Especially at cooler temperatures the grease will be congealed somewhat. Plus once squeezed out has no reaon to work it's way back into the needed areas.

I am a believer in the heavy oil approach. Technically it may not be as much of an issue on a joint that has absolutly no wear. I just do know why they switched over to grease so late in the game. If they had felt it really better they would have used it from the start.

vstech · #5 01-18-2011, 08:06 PM

on the axles I pack with grease, the bags that come with the universal fit boot is insufficient to fill the cans. I start with the axles pulled out, and tilted all the way to one side, then PUMP the grease under the spider. then I keep the axle pulled out and finish off the bag, and get a new bag of grease and nearly 1/2 of the extra bag gets packed in.

Diesel911 · #6 01-18-2011, 08:57 PM

Quote:

Originally Posted by barry123400

Especially at cooler temperatatures the grease will be congealed somewhat. Plus once squeezed out has no reaon to work it's way back into the needed areas.

I am a believer in the heavy oil approach. Technically it may not be as much of an issue on a joint that has absolutly no wear. I just do know why they switched over to grease so late in the game. If they had felt it really better they would have used it from the start.

There is at least 2 threads debating Grease verses Oil.
The fact is most of the vehicles on the road that have CV Axles are have Grease in them.
Until I was a member of this Forum I never knew that a Car maker would fill them with Oil.
I think there is advantages to both. The Oil may give better lubrication in the long run but if the Boot loses integrity the Oil can leak out.

bustedbenz · #7 01-18-2011, 10:48 PM

There are a lot of cars out there with grease in their CV joints, but there are also a lot of cars out there with recalled brakes, a tendency to explode when crashed, and all sorts of other things. Fact is, I believe oil is simply a better product for the application.

Grease by definition doesn't move around as freely as oil. In a part that's changing orientation constantly, it stands to reason that once the grease wiggles its way into a position where it's not doing any good, it's going to be very difficult to persuade it to work its way back into the actual moving joints. Oil, since it flows, can get in all of those places -- provided you don't under-fill it (centrifugal force keeps it from reaching the center except to leave a film when stopped) or have leaky boots (as diesel911 mentioned).

When I rebooted my first set (240D was clunking around terribly) we put heavy gear oil in, with nothing else. No problems yet. The 300SD was looking a bit ragged, and we were working on it and the 300SDL simultaneously, so I decided to get hold of the gun one more time (Thanks again VStech) and do all of my remaining ones need-it-or-not just so I wouldn't have to worry about it. These, I refilled by packing the full pouch of grease that came with the boots into the joints -- and THEN filled the cans with gear oil. Figured I'd take a chance on there not being some kind of glue-making reaction, and that the combination would eventually mix together into one big greasy-oily slurry that would keep everything lubricated. Again... so far so good.

Main question in my mind is how long those flexx boots will actually last. I'm HOPING (and gambling) that they've got a long life span, but if they fail in 5 years I guess I won't be shocked either. It's awfully thin rubber... that's what gives it the ability to flex without stressing, but... it sure wouldn't take much weathering to beat through them. I'm using a grand total of 12 of them at the moment so I guess I'll find out.