Need oil recommendation, vintage engine...

[fraso]

I haven't come across any old GM manuals but the oil & kerosene suggestion sounds very similar to Chrysler Oil Recommendations.

 

[lexus114]

Originally Posted By: mechtech2
BTW, I am loosely affiliated with a '38 Buick. I am surprised in 1947 they still use the old oil specs and esp the kerosene trick in the winter.



That would clean out the motor!

 

[Merkava_4]

For a 1947 Buick straight 8, after the initial break-in with 10W-30, I'd switch it to SAE40 or 20W-50 on the next fill.

 

[fraso]

If the maintenance recommendations for a 1947 Buick were anything like the old Dodge recommendations, a 40-weight oil was only recommended for hot weather driving and 50-weight oils were never specified. I think any 30 weight multigrade oil would be suitable, especially since the original oils would have only been the equivalent of API SB. If the OP is driving his car through the winter, any brand-name 5W-30 PCMO would be a good choice. I think HDEOs would do a better job of controlling sludge and the higher levels of zddp won't hurt.

Like Widman suggests in the Corvair Oil Article (Bottom Line Recommendation #10), if sludge is a concern, use a good HDEO (he recommends CH-4/SL or CI-4/SL) and keep changing it as it thickens up.