Freightliner rear diff fluid change

[smlranger]

OK, so how many with Frieghtliners really change the differential/rear axle lube as often as recommended in the manual? I had mine changed about 30,000 miles ago and they used Mobil 1 synthetic lube. I just don't see the logic in needing to change that lube very often.

[Pigman]

Meritor changed their recommended change interval to 50,000 mi or one year. Synthetic oil is 250,000 or 3 years. I have a Meritor letter to that effect.

John

[Hooligan]

smlranger:
Meritor Bulletin TP-9539 shows the lubrication schedule and approved fluids. It's available here. http://www.meritorhvs.com/MeritorHVS...nts/TP9539.PDF

Three year changes are much more reasonable!!!

[J Walker]

On my Freightliner XCS chassis the specified change interval for the differential fluid is 2 years. Miles never enter into my change intervals on the differential or any other thing on my MH. The only reason I can see for the time specification on differential oil change is condensation of water. Still I feel that the specification is very conservative.

[JoeT]

A Freightliner tech told me the reason for the frequent change interval is moisture and it affects synthetic as well.

[leedowney]

Hey smlranger. Did you change the rear diff fluid yourself or have someone do it for you? If you did it yourself, was it very difficult to do? My Journey has about 40K miles on it and the previous owner wasn't much on keeping service records. It is on my short list of things I still need to do as well as changing the air filter and transmission fluid/filter. I bought the coach this past December and each weekend, I tackled a new maintenance task that I feel needs to be done. I sure wish the prev owner would have kept better records. When I called and asked him when the last time the "Air Dryer" had been serviced, he thought I talking about the "hair dryer" by the sink in the bathroom. I knew right then, he was not the maintenance junkie that I am.

Is there a link or diagram on instructions for this task or the other two I mentioned above (air filter or Trans fluid)?

Thanks smlranger.

[Hooligan]

Rear differential, remove the fill plug and the drain plug on the bottom, drain completely. Refill with 80w90 gear oil or 75w90 synthetic gear oil.
MERITOR RS-15-120 axle holds 16 pints.
Axle lubricants: http://www.meritorhvs.com/MeritorHVS...nts/TP9539.PDF

Freightliner Maintenance Manual for Rv chassis is here. FCCC Motorhome Chassis: Manuals Click operator/maintenance manuals. Then select maintenace tab then rv maintenance manual.
I put the link for approved rear axle lubricants above because in the freightliner manual, *** THERE IS A MISPRINT-Section 35-02 Rear Axle Oil Change "Refill axle with Transynd ATF" :: SHOULD BE GEAR OIL !!!
I use a manual lube pump that screws into the gear oil bottle to pump oil into the axle. (auto parts store)