Originally Posted By: NYBob
Thanks, everyone for your responses. I'll need to look into a pre-luber if I can keep it discreet. Otherwise the Delvac sounds like a possibility - I'm just looking for something that will cling for a long time & pump up quickly. I'm not sure if it will harm anything if I use a 5W weight.
The engine was rebuilt to stock clearances & parts (with the exception of hardened valve seats). The type of driving I do is typical cruising where I drive a lot around town & then blast it up & down the highway some
Brad Penn was mentioned earlier, I never heard of it - but looking at their website, it seemed interesting.
I have a couple of questions.
I've read on this Forum that many people don't like Royal Purple, are there any drawbacks to using it for such low mileages between changes?
Anyone have an opinion about ZDPlus? I could go back to Mobil-1 & just add 1/2 bottle of that if it is really compatible. Or should I just use Amsoil, it seems to be real popular & has plenty of ZN & Phos.
I have a '73 Coupe DeVille. No show car just a driver. I'm an OTR truck driver so it sits for 3 weeks at a time. Usually only about 2 though.
I use Mobile 1 15-50 in it year round now. Though for a few years there I changed to the 10-30 in the winter.
It gets down into the 20's in Utah and it does turn over slower when it is that cold but the difference I noticed with the 15-50 is that when I start it up after it has been sitting for 2 to 3 weeks the oil light never even comes on where as with the 10-30 it stayed on for a few seconds.
I always let it warm up before I drive off which is the secret to using heavier oils but even though the 15-50 EP has 1200 PPM of ZDDP I add ZDDPlus at every oil change because the older oils of that era had as much as 15 or 16 PPM of ZDDP.
Your 428 has a MUCH stouter cam than what they put in a Cadillac so I would definyely recommend adding some ZDDP even if you use Amsoil or another high quality product. Maybe just a half a bottle with Amsoil or Red Line though.
IMO if I had YOUR car I would probably use Amsoil or Redline. I don't need an oil that good for my car because the Cadillac 472's are NOTORIUOSLY under stressed and have INCREDIBLY weak valve springs. Although they DO run very hot by design. I probably don't even NEED the ZDDP additive but it IS good insurance.
Just my 2 cents.