2004 differential goes out

I'm still trying to figure this out. Where did the common belief come from implying that because a product claims that it is "synthetic" on the label means that it is better than the OEM approved/specified fluid?

To the OP: Yes. sometimes bearings/gears do fail early due to fatigue or other manufacturing defects. It is rare. Without more information about your specific failure (pictures, history, etc.) it is a waste of time to speculate.

Chum lee

But I did learn why European drivetrain components could not tolerate non-specification lubricants. Miami screamed about cost. Meanwhile back at the ranch, Reno, fell into low single digit customer complaints. The Carter flaming Thermoquad problem was solved by wrapping aluminum backed insulation around the fuel line to the carburetor. The Ford blinking lights headlight switch issue was resolved with the installation of a relay. The Ford cube van stalling problem was harder to fix. Because the fuel pickup inlet was placed at 60% of the height of the tank. Any lower fuel level than 60% the unit would run out of gas (I discovered this at 0200 hours in Winnemucca, NV.)

Wotta Hoot. Troubleshooting P.T.

MEXICOWANDERER wrote:
***JARTRAN*** I was hired for a six month stint to try and straighten out nightmare service problems with the trucks.

***JARTRAN*** Forty years ago, my wife and I led a team from our church that transferred JARTRAN trucks around FL as a fund raiser. The number of those trucks that died on us was staggering. Most transfers were Cube Vans on Dodge. Clogged mufflers, failed charging systems, but worst, they SLUNG BELTS. That's the ones where the plastic Holley ThermoQuad carburetors didn't catch fire. The ones on E350's weren't as bad. The 22-footers on F650 were a joy to drive but few and far between.

I'd plan, JT would change. I'd plan, JT would cancel. I'd call JT and no transfers till they called Friday night wanting Saturday.

Now I know why BOTH of us have Heart Trouble.

In this day and age a lot of manufacturers of vehicles and or vehicle components do their development work with an oil supplier and this supplier makes additive changes to their product for that manufacturer. Even without government mandates purchasers of OTR vehicles are looking for mileage improvements. Do the math on 15 trucks running 100s of thousands of miles per year and a .5% increase in fuel mileage enhances the bottom line significantly. So, unfortunately, using an aftermarket/non-approved oil can have detrimental effects on the life of a component. I can give you one example that will never leave my memory banks. Our shop had an area referred to as the penthouse. It was on a separate level and accessible through a single door. The guys that worked up there never knew that there was a reason for having 2 gear oils in the overhead and only used one for diffs and transmissions. All of the differentials serviced in the penthouse started to make noise. They were putting the non-hypoid gear oil in diffs and the gears would gall slightly. On the other hand I have seen guys put hypoid oil in a manual transmission and wonder why they no longer shifted smooth. The syncros would notgrab on the gear face. One simple additive can have a profound effect on the service life of a component.

Dana rear out at about 105k...maintained, never abused. Weller two years ago, smooth, quiet. Synthetic per Dana/Weller/ Kenworth dealer that did the work.

http://bevo.mercedes-benz.com/bevolistenmain.php?language_id=1

Grab can of your "synthetic gear oil" and start searching these Mercedes specifications. Your failure I strongly feel was artificially induced. Volvo, Magirus and Mercedes.

Forty years ago Magirus was the truck of choice for JARTRAN. I was hired for a six month stint to try and straighten out nightmare service problems with the trucks. Failed transmissions and differentials. Mercedes, Volvo and Magirus used the same driveline components. I ---- canned the Paris Rhone alternators and switched to Bosch. That problem ended dramatically.

But they insisted that Eurospec lubricants be used. Pure 100% factory approved.

I fought Miami Florida hdqts and purchased carboys of OEM lubricants (expensive) changed all the lubricants and guess what (?) the failures stopped.

Best of luck to you.

A big truck differential is like a Allison 3000 tranny...something you do not worry about. At 85K miles I have no plans for changing my gear oil. I think you just had bad luck.

MB is not RR, but close, so let's repost old joke about high-end vehicles.

old joke wrote:
British pride in native products has not dimmed.
A London plutocrat was driving his fine new Rolls-Royce over the Alps when he heard a disquieting “twang.” His front spring had broken.

He called the Rolls plant in London by long distance, and, in what seemed like no time flat, three gentlemen arrived by plane with a new spring — and off went the plutocrat on his interrupted jaunt.

Now comes the really interesting part of the story. After six months the plutocrat had received no bill from the Rolls people. Finally he appeared at the plant in person and asked that the records be checked for “the repair of a broken spring in Switzerland.” After a brief delay the manager of the plant appeared in person, gazed at him rather reproachfully, and announced, “There must be some mistake, sir. There is no such thing as a broken spring on a Rolls-Royce.”

Folks

All of these comments about the automatic transmission are interesting but have nothing to do with my problem. My rear differential failed. I am trying to find out if any other people have had any wonderful luck like I just had with their differential that was made by Mercedes in 2004 or around that time.

Ken

.............The Key (Repeated)........................

Is/was the synthetic oil specifically approved by brand name and weight, by Mercedes?

Mechanics, Snake Oil advertising, and bad advice abound. After digging HARD AND LONG into whether or not MoPar approved synthetic transmission lube is mandatory for my toad, facts finally emerged. Sourced at MoPar

Synthetic lube is NOT mandatory, however the transmission life will be greatly enhanced because the "MoPar approved synthetic fluid does not decompose at elevated temperatures, and offers a better level of lubricity compared to proper grade of petroleum ATF".

I elected to stay with the much more costly MoPar approved ATF.