found torque specification for oil pan bolts
Thanks for the respondants who replied my post. I managed to sort out the reason for the confusing differences in the torque specification for the bolts. I found the recommended spec. from a GM 1992 Pontiac Sunbird Technician's Service manual.
What it says is for my car with the 1992 year, 2.0 liter 4 cylinder engine (
VIN code 'H') the oil pan bolts require only 8 foot pounds (96 inch pounds) or 11 Newton Meters of torque.
For the 1992 year, 3.1 Litre 6 cylinder engine (
VIN code 'T') the rear 2 oil pan bolt torque specification is 18 Foot Pounds or 25 Newton Meters.
The 4 cylinder engine has a oil deflector and gasket assembly that sits on the oil pan and has a flange that is sandwiched by the oil pan lip below and engine block above. There are 2 gaskets above and below the deflector lip that seal the mating surfaces to prevent oil leakage between the oil pan lip and the engine block.
The deflector serves to prevent oil from unwanted splashing upwards on areas above the oil pan where lubrication is not necessary. It serves a someone similar but not identical finction as an oil pan windage tray that is used in some performance high revving GM engines.
I don't know if the 6 cylinder has the oil deflector. As one of the respondants mentioned this may be why the oil pan bolts for the 6 cylinder has a higher torque spec. for the oil pan bolts.
So today I mentioned to my mechanic who replaced my original oil pan and gasket (which is 22 years old) with new parts, to not overtighten the oil pan bolts and to torque them to no more than 8 foot pounds. -Joseph-
