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Differential oil change interval

I have a 2007 Dodge Ram 3500 6.7L diesel 4x4. The owners manuel say’s to change the oil in the front and rear Differentials every 15K miles. Why so often? The dealer gets $100 per axel for this maintence so i have been doing them myself, but with the cost of lube these day’s it still costs me over $80 in oil. When i asked the dealer they just said that’s what the manufature recomends. Differentials used to go 100,000 between changes. The only change i can figure out is Dodge used to uses Dana diffs and now use American axel. What do you think?
Thanks
Craig

If you tow, go off road, or live in a severely cold climate, or have a positraction or limited-slip diff, MAYBE this would be a good idea. But I can’t imagine why you’d need to change the oil this much. Maybe because of the heavy duty nature of your truck, and the assumption that it would have severe duty.

If you don’t tow a lot or otherwise abuse it, I’d consider changing it maybe every 50K or so and using a good synthetic lube.

What did you read? You read it in the owner’s manual and that matters. If you think that changing the fluid is expensive, wait until you find out how much it will cost to repair those diferentials. $4,000 or more will buy a lot of oil; if you have the $4,000. Plus, when the repair is done, will the problem be done too? Maybe, maybe not. American Axel might be the problem. If they can’t spell it, how can they make it? Maybe Axel Rose owns the company.

I didn’t say i wasn’t doing the oil changes at 15K i was just wondering why it was so often . I am sure that American AXLE is not the problem as they DO spell it correctly i did not. Thanks for your smart ass reply.
BTW Alex Rose sucks!

The severe service schedule for axle oil has been 12,000 or 15,000 miles since the mid 1990’s. Corperate, Dana or American axles.

In my experience the front axle oil that is drained is very clean, the front axle is usualy just coasting. Unless you do alot of off-roading, drive through water or plow snow I would only change the front axle oil every 5 years.

“Driving in dusty conditions, frequent trailer towing, Extensive operation at high engine speeds (greater
than 2900 rpm) and loads (greater than 70% throttle).” Severe service may not aply to you (I don’t think “extensive idling” or short trips affects the axles). You may be able to go 30,000 to 50,000 miles between rear axle oil changes.

If you change the oil yourself note that American axle differential cover gaskets are reusable.

See if you can buy 5 or 30 gallon drums of the oil.

I assume you have 4WD I would suggest that you should not skimp, even a little on that maintenance. Follow the owner’s manual (as it appears you have been doing) as a minimum.

Good luck and congratulations on doing your homework.

I’d personally worry a little more about the transfer case oil if you have 4WD.

I’m with Nevada_545; I am reluctant to say the front and rear should be changed at the same time if the front is used much less. If you change then at the same time, you will find the front looks almost new.

The biggest reason might be if you have a limited slip or automatic locking rear differential with more “expensive to replace” moving parts. That along with heavy use would account for more frequent rear change. Unless you went through water off roading, every other on the front and normal change interval on the rear according to the manual. Beware…most problems in the front occur because of too little use, not too much and changing the oil frequently in the front does nothing for that. Run the fronts at least 20 minutes continuously every month.

I have a 1991 W250 Dodge P/U with 160K miles and I have NEVER changed the oil in the axles…Changing it that often is silly unless you do a lot of stream or other deep-water crossings where water might get in…

A little trick I have learned is to place a powerful magnet on the inside of the cover to pick up and remove any metal filings that gearboxes can produce. The rare-earth magnets removed from computer hard-drives work best for this…

Follow the owners manual? This is a statement from the owners manual;

Drain And Refill
Vehicles operated in normal service do not have regularly
scheduled oil changes. If fluid has become contaminated
with water or subjected to severe service, follow the
recommended change intervals in Maintenance Schedule
“B” in Section 8 of this manual.

Schedule “A” is for for normal service, requires no axle maintenance.
schedule “B” severe service, reqires axle maintenance every 15,000 miles.

My vehicle use falls somewhere in between, I change my axle oil every 30,000 miles.

Or even every 60,000 …That’s far more often than most vehicles get…

I think passenger cars easily go 150k miles with no change.
I changed mine at 120k for the first time.

It is a VERY easy DIY job, so you might as well learn to do this
All you need is this: for $12
http://www.autozone.com/autozone/accessories/Autotec-16-oz-suction-gun-with-12-in-flexible-hose/_/N-255s?itemIdentifier=142102

And I didn’t spell Axl Rose’s name right either. Oh well. Happy we have all the speeeling right. It’s hard to be perfect when I’m humble in every way. I wouldn’t want to do those oil changes every 15,000 miles either. I guess they figure that if somebody owns a one ton with 4WD, they must be using it for some rugged duty. The only thing that does rugged duty on my truck is the windshield. There are lots of bugs in Northern Maine and the speed limit between Orono (Bangor) and Houlton is 75. 115 empty miles and I had to make the trip so I could see the only person I know in Caribou. Love that speed limit.

Thanks for all the info. I think i will do the oil changes at least every 30K because we do tow a 12500lb 5th wheel. It will be interesting to see what the oil looks like at the next change.
We are finding this truck is very expensive to maintane. Axle oil $100 every 15K Transfer case $80 at 30K fuel filter $100 every 15K engine oil change $70 every 3500 miles ( owners manual says 7500 miles but the oil change light comes on at around 3500) Dealer claims engine oil needs to be changed more often to to stop n go city driving. I didn’t really buy that until i changed the oil right before a 8000 mile long trip towing the 5 th wheel and the oil change light came on at 7400 miles

Cost money to play with the big boy’s. Truck does have awesome pulling power

@disqgolfer: The next time you change the diff oil, why not send a sample out for analysis to determine what shape the used oil was in? You could probably base your change intervals on that. Blackstone Labs (google them) will do the job for around $25 I think. If you inquire with them, they will send you preaddressed sample containers as well.

I used to want a big truck just for fun. When I started finding out just how much routine stuff like brake jobs cost, I figured to just keep muddling along with half tons. I don’t have to tow anything. By the time I get back to Ca. to bid on storage lockers, there will be so many people doing it that it will be impossible to win one. I still won’t have to tow anything.

Wait the oil change light comes on at only 3500 miles?? That seems very low for a truck like this. Are you sure the system is getting re-set at each oil change?? I ask because unlike what most people think, there is not sensor in the oil pan seeing how much life is left in the oil. ALL oil change monitoring systems are basically complex mathematical algorithms, that take into account air tem, motor temp, RPM’s, start/stop cycles, etc… IT MUST be reset at every oil change to even be close to right… You also MUST use the correct oil, or the calculations will be wrong. With that said, I think 3500 is too short of an interval, especially on a dsl assuming you are using a good dsl oil like Rotella or the like.

As a side note yes your oil life will drop much faster around town then on the highway.

Yeah i thought 3500 was to short too but if ya check the Dodge forums it is a common problem on the 2007 and newer trucks with all the emissions controll stuff. Owners manual say’s " Up to " 7500 max but to follow the oil change light.