FL Differential Annual Oil Change?

[Old Snipe]

The FL XC-S chassis on my WB Journey requires an annual oil change of the Meritor differential. I just had it serviced at my local FL shop, they were of the opinion it wasn't required until I showed them the maintenance schedule that came in my owner's packet. They changed the fluid and replaced it with Mobil 1 synthetic differential fluid.

My questions are:

1. Why is this an annual requirement, I thought the diesel chassis were heavy duty, I didn't have to change the differential oil this often on my previous MH with the Workhorse chassis.

2. With the Mobil 1 synthetic diff oil, now can I extend the change intervals to every other year or even three?

Thanks and Best Regards!

[Old Snipe]

The FL XC-S chassis on my WB Journey requires an annual oil change of the Meritor differential. I just had it serviced at my local FL shop, they were of the opinion it wasn't required until I showed them the maintenance schedule that came in my owner's packet. They changed the fluid and replaced it with Mobil 1 synthetic differential fluid.

My questions are:

1. Why is this an annual requirement, I thought the diesel chassis were heavy duty, I didn't have to change the differential oil this often on my previous MH with the Workhorse chassis.

2. With the Mobil 1 synthetic diff oil, now can I extend the change intervals to every other year or even three?

Thanks and Best Regards!

[Harry B]

Paul,

I had the same questions last year and consulted both FL and Meritor. The answer was the same for both, which was that they are concerned about moisture buildup due to the lack of continues operation.

I also raised the issue of putting in synthetic oil and if I recall correctly the mileage interval changed to 240,000 miles but the time interval remained the same namely every year.

Based on that information I decided not to put synthetic oil in, as they frequency to change the differential would still be annual. I don't drive 240,000 miles per year.

I am still not convinced that it needs to be changed that frequently but for now I do it. Perhaps someone else can chime in on this as well.

[Hooligan]

Old Snipe; Try this link, Meritor
I have xcs Chassis, Meritor RS-15-120 Rear. With approved synthetic I read 3 years. That's the good news, Bad news is I don't see Mobil 1 Syn on the list.... ( I use the Fleetrite synthetic only because the local International dealer stocks it and the Fleetrite and Midland filters reasonably)
Hope this helps.

[Old Snipe]

Thanks guys!

I went back and looked at my receipt and it was Mobil Delvac Synthetic. When writing my post, I crossed up the Mobil 1 moniker because I am so used to that name.

So I could be good for three years, but for the small cost of changing the fluid vice the price of a replacement differential, I guess once a year it is.

I wish I had the time to run my MH 240K miles!

Best Regards!