M60 idle - lend me your ear

[m60power]

I always used 20w50 in the M60. I still use it in my 4.4, M60 heads and M62 block. Uses no oil, runs quiet.

Lighter viscosity oils resulted in increased oil consumption in my M60. I would not use anything thinner than a 15w40 in a pre-99 V8. 99 and later were designed from the factory for use with 5w30 synthetic and use different rings and bearing clearances to suit.

I use Castrol 0w-40 in my m60 motors in Florida all year. Even the highest mileage one (~220k miles) uses less than half a quart in 7000 miles. Although, I wonder if the zero weight may lead to increased bearing wear if these motors have looser bearing clearances?

[nonturbodan]

Probably nothing to worry about. The 40w viscosity at operating temp is reasonable.

[moroza]

0W40 Mobil 1 - used it once a long time ago. Remember it ran fine but no details. Was quite clean when changed at 10k.
5W30 Castrol Edge - used at least twice. Collapsed lifters after sitting for a month or two, was medium-brown at 11k. Oil pressure light a bit more active at cold starts than with other oils.
5W30 Amsoil - used a few times, engine feels smoothest and happiest with it, stays clean longer than I cared to find out (10-15k).
5W40 Amsoil - used once. Similar to 5W30 but revved slower and lost ~1.5mpg.

I changed all my oil seals (including the rear main) with OE parts 7 years and ~60k ago, and used good full-synthetic oil ever since. One oil (don't remember which) burned ~1L between changes - all 10-15k - the rest less than half a liter. There's ~215k on my engine. All were used between -10C and +40, the Castrol down to -16C cold-starting and -20 or so prolonged driving. It seemed to have no trouble with the cold, I was impressed. (Had a lot more trouble with snow and ice, I was not impressed. Also 12.7mpg that winter.)

[84318i]

Thanks , appreciate your feedback moroza!