I have truck and fifth wheel trailer posted below. The truck is stock. The truck miles make up about 60-70% of total mileage. The weight is very close to the maximum GCWR of the truck. I just did my 30,000 mile differential oil changes. I am starting to think this recommendation is a little over the top. The fluid looked as good as when I put it in 15,000 miles ago. Do you guys have any thoughts on this?

 

I periodically pull the plug and stick my finger in- if moisture is in the oil, it will be frothy. If the oil looks good, which it always does, I put the plug back in and keep going. High heat and water are going to be you biggest enemies- if you drive sensibly and aren't fording deep water, then I think you can go longer between services.

 

170,000 miles and I had to adjust the axle bearings and replace one axle seal. The synthectic oil I put in at 50,000 still looked good, will change it at 200k.

 

I change the oil in my diffs at 15000 mile intervals too; clean oil can never be a bad thing.

 

I changed the rear at 15K, oil still looked clean, changed front and rear at 30K, both still looked clean, added the Mag Hytec pan on the rear. I'm almost at 60K and plan on changing both again, but will likely wait until 120K to change them again.

I don't tow more than 10K a few times a year, most of the miles are commuting. I agree than clean oil is better, but these changes cost about $120 (just fluid) and in my previous trucks the synthetic fluid has been rated for 100K or lifetime. If I were towing 15K daily I'd keep up the 15K intervals.

 

07 ram 2500...rear diff oil change..do i need friction modifer or not??

 

I was told no on the friction modifier and that the LS is not a clutch type.