My 96 Seville has the 4.6 Cadillac Northstar and I've run it on mostly Mobil 1 10w30 and either PureONE, Bosch, or AC-Delco filters. It's at 96,xxx miles now. I probably only put 8-10k miles/year on it these days. When I didn't use Mobil 1, I used Pennzoil or Valvoline conventional 10w30s. Well, I've come to the conclusion that synthetics are not worth the price, and I'd like to use 5w30 for the cold winter months here in Chicago since I have to park outside all day. I typically follow the advice of the Oil Life Monitor in the car, which usually gets me between 6000 and 7500 mile OCIs. I have a stock of 2 Mobil 1 filters and 10 qts. of Mobil 1 10w30. So the question now is, do I use a 5w30 conventional for the winter and then just use up my Mobil 1 stock next year, or would the Mobil 1 10w30 have better cold start protection than a 5w30 conventional?
I understand that Havoline, Pennzoil, Motorcraft, and Trop Artic are good dino motor oils. What about Valvoline, QS, Castrol, and Mobil? Which 5w30 conventional should I use for the winter months if the Mobil 1 10w30 should be saved for next summer? Beyond that, when my Mobil 1 10w30 stock is gone, which conventional 10w30 would work best for my car?
As a little background info, the N* engines seem to have a tendency to burn a little oil. I regularly give the car healthy doses of wide open throttle to help clear up the ring lands and blow out the carbon, but it still burns up the same amount of oil. The engine holds 7.5 qts. with a new filter, but I usually put 7 in it and refill when it's about 1 to 1.5 qts. low. So, over the course of a 6-7.5k OCI, I probably put 2 or 3 qts. of top-up oil in it. Keeps the additives fresh, I suppose.
It's my daily driver and I only have a 5-10 minute commute every day, so it doesn't get up to full temp very often. My goal is to maintain the car properly, and to do that as inexpensively as possible from now on.
Many thank yous in advance for any advice and guidance you can provide.
I understand that Havoline, Pennzoil, Motorcraft, and Trop Artic are good dino motor oils. What about Valvoline, QS, Castrol, and Mobil? Which 5w30 conventional should I use for the winter months if the Mobil 1 10w30 should be saved for next summer? Beyond that, when my Mobil 1 10w30 stock is gone, which conventional 10w30 would work best for my car?
As a little background info, the N* engines seem to have a tendency to burn a little oil. I regularly give the car healthy doses of wide open throttle to help clear up the ring lands and blow out the carbon, but it still burns up the same amount of oil. The engine holds 7.5 qts. with a new filter, but I usually put 7 in it and refill when it's about 1 to 1.5 qts. low. So, over the course of a 6-7.5k OCI, I probably put 2 or 3 qts. of top-up oil in it. Keeps the additives fresh, I suppose.
Many thank yous in advance for any advice and guidance you can provide.
