Synthetic motor oil

1989 CHEVROLET SUBURBAN
200 MILES • V8 • 4WD • MANUAL
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DOODLE50
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I have a RamJet 350 Crate Engine PFI with Iron Vortec Heads in a 1989 3/4 ton Suburban. I bought it second hand with low miles and stuck it in. My question is regarding oil pressure and synthetic oil. This motor has always had Mobil-1 synthetic. The pressure is high at initial start up but after the motor warms up the pressure seems low to me but I have no experience with synthetic oil. Should I be running a high volume oil-pump?
Dec 16, 2010 at 4:56 PM
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DAVE'S BIG BACKYARD!
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first make sure its the right weight oil.then you might want to check the oil sending unit,after that it gets pricey.
Dec 16, 2010 at 5:29 PM
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HMAC300
  • ✓Experienced Mechanic
  • 48,601 POSTS
no all oil presssure in these motors drop after the oil heats up no matter if it's synthetic or mineral oil. if you runabout 40-50 psi at about 2000 that's ok, if it drops to 20psi or around there that's about normal. anytime you suspect an oil pressure problem always use a mechanical gauge.
Dec 16, 2010 at 5:56 PM
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DAVE'S BIG BACKYARD!
  • EXPERT
  • 262 POSTS
yes oil doe's bake thin in all engines.that is as long as the pressure dont get to low,yes a gauge is best.auto parts stores have the specks&or a book on the engine.
Dec 16, 2010 at 6:22 PM
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