Originally Posted By: Jaymus
Originally Posted By: mpvue
Originally Posted By: Jaymus
The biggest savings will come from going to synthetic in a manual transmission and rear end. Now, going from, say, 10W-30 conventional to 0W-30 synthetic might save a fraction during warm up.
I had hoped for that in my '96 mazda MPV, a true MPG pig. factory rating is IIRC 12/18. engine is freshly tuned, new timing belt, almost full amsoil (ft and rr diffs, trans, engine, just didn't do the transfer case) and I didn't see any appreciable improvement; mixed driving is still around 15, same as before fluid changes.
Well, that sucks, lol. I did this in my 1986 F-150 old school NP435 transmission and Ford 9" rear end, and gained probably 2-3 mpg. The stuff that was in it was thick and orange... probably factory fill. But I know it wasn't synthetic, lol. I'm surprised for your case.
perhaps if I used this truck for commuting I might be able to see a mpg advantage, but it's our family truckster, lots of local stop and go.
to be fair, mpg wasn't a 1st priority for the syn switch. I was more interested in longer OCIs and winter protection. it runs real well, pretty torquey engine. it is a heavy vehicle w/ only a 3.0 V6, so I wasn't expecting miracles.