351 using oil

matpasch · #1 (**permalink**) 11-05-2009, 01:54 AM

My 1993 F250 4x4 ext cab with 351 Windsor and 5spd seems to be using about 1 liter of oil every 1200-1500kms or so. The truck doesn't leak pil, no blue smoke or smoke at all, no smell. It has just over 300,000kms on the engine and just did a tune up, new pvc valve etc.
Im running 10w30 right now up in vancouver Canada. wondering if I should use a heavier weight oil like 10W40 or 20W50? Would this harm the motor, in the winter, never gets that could here. I run 20W50 in my 70 Torino with a 460, but it burns blue and never sees the winter.

thanks
mat

g_k50 · #2 (**permalink**) 11-05-2009, 12:21 PM

When you say leak, do you mean a spot on the driveway or do you mean a oil trail on the motor or congealed on the underside of the body? Because it sounds like a leak, and you've gotta have some leaking valve stem seals. How do the spark plugs look?

The 351w could use a heavier weight oil, 20W would not hurt that motor and maybe even a 30W in summer.

Kemicalburns · #3 (**permalink**) 11-05-2009, 12:42 PM

well with the cold coming i would stay with what you are using now. staying with the same oil year around is best practice for an old motor like that. you are probably getting some blowby the rings or the valve seals which is typical with that many miles on the motor. i wouldnt worry about it honestly just keep an eye on it. i would install a mechanical oil pressure gauge so you know whats going on there. the stock gauges suck.

matpasch · #4 (**permalink**) 11-05-2009, 02:52 PM

Sparkplugs are clean, no okl on them. Ya a mechanical oil gauge would be good, probably get a 3 Pack and install them