Mobil 1 Syn Gear Oil

[MasterChief]

I have been using Mobil 1 SYN Gear Oil 75W-90 in my differential . The book calls for it to be changed every 15K. The last time I changed the gear oil it looked like it was fresh out of the bottle. I am thinking about moving the change interval to 30K.



Any thoughts or comments are welcome



Thanks

Mike

 

[rbattelle]

After 60k miles of 15k changes, I've moved up to a 30k change interval. Same reasons as you: fluid looks fresh-from-the-bottle after 15k.

Ryan

 

[Salt Dog]

30,000 change interval for me too. !

 

[dan.poitras]

Once a year here for all oils including power steering fluid and brake fluid flush irreguardless of mileage.

I plan on keeping this truck a long time

 

[steved]

IIRC, if you read the two schedules, the one (severe) requires 15k and the other has no scheduled change...

steved

 

[Vaughn MacKenzie]

I went 30k running Amsoil in my Dana 80 and even after that many miles it looked like I'd just put it in, still nice and blue. There was nothing on the magnet. I coulda let it go 50k since I didn't tow a lot.

 

[Bachant]

Every 30,000 for me also. It comes out clean and almost nothing on the magnetic drain plug on the after market cover.

 

[SDeVries]

Mike, I would run the gear oil as long as it looks fairly clean and didnt have a burnt smell to it. Where I work, on semis, we run mobil1 for 300,000 miles and still looks good. If your hauling real heavy loads you can switch to 85-140, also Amsoil has severe gear 75-110 . I hope this helps Harley hauler, 07 5. 9 aut 4x4. Stock for now...

 

[JGheen]

I did the same thing, moved it up to 30K miles but I think I will even go longer. Mobil 1 is too good of oil as well as too expensive to be spending over $100 on gear oil every 15K miles.



Joe

 

[Cattletrkr]

I change mine at 30-40K... whenever I feel like it. I've sent in for UOA at that mileage and it comes back "suitable for continued use".

Even expensive oil is cheap compared to problems.

 

[MasterChief]

Thanks all; I'm going to change at 30K and if it still looks good I might go to 40 or 50K.

 

[nickleinonen]

every 2 years or so... i did the rear this year, but skipped the front. i went to syphon some out of the front, and it was still golden orange like what i put in 2 years ago, so i just topped it up and let it go. the rear i drained, but it was golden orange in color like the front. . shouldn't have drained it, but oh well. . i think i will let it go 3 years this time [3 years for me is about 45,000 kilometers]