Rear Diff Change

[Road Warrior]

At 28,000 miles I just changed the rear diff to a group IV synthetic. I immediately noticed a quieter running vehicle...not that it was loud before. To use an audiophile term.....I guess I would just say it lowered the 'noise floor'? Anyone else experience this?

I have to drive from Buffalo to New England and back this week. I'll have to see if their is a measurable mpg improvement also!
RW

 

[MikeInNH]

I'd be surprised if you saw ANY MPG change....VERY SURPRISED.

I changed the fluids on my 98 Pathfinder. Went to all synthetic....I went from 310 miles per tank ...all the way up to 320 miles per tank.

As for the noise...If you were able to hear the noise then I think you might have a problem. Normal tire and engine noise should easily drown out any diff noise....unless it's REAL loud...which it shouldn't be.

 

[Jacobzky]

it will reduce friction and have a better protection. i cant really tell if i gain mpg changing the diffs to synthetics.

 

[Indy4Runner]

I suspect that any real noise reduction occured from changing your diff fluid was psychological and I doubt that you will see an improvement in mileage.

So I guess you'll just have to settle for having one of the best trucks on the road. Enjoy your trip!