Black betty Posted September 28, 2018 Report Share Posted September 28, 2018 Hello i now run 20-50 oil with zinc additive my oil pressure at cold start ( 50 degrees and above ) is about 38 or 39 lbs at full warm up On a hot day i am at about 20 lbs is this ok your thoughts tx c Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted September 28, 2018 Report Share Posted September 28, 2018 10 lbs per 1000 RPM......you are good...….if you idling at 20 <1000 you golden.. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted September 28, 2018 Report Share Posted September 28, 2018 Why do you think the engine needs extra zinc? Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted September 28, 2018 Report Share Posted September 28, 2018 2 hours ago, Don Coatney said: Why do you think the engine needs extra zinc? Uh oh...not this debate again! LOL I use zddp additive in both my truck and my 67 Monaco, todays oils don’t contain the amounts we need, other then oil for classics like Joe Gibbs etc, but I find those very expensive and prefer to run moderate priced oil with additive. Im running about the same oil pressures, 50 cold and mid 30s hot at idle and that’s checked with a manual gauge as well. If you were over 50 I would maybe be concerned that you have a pressure relief valve issue, but a well built engine should be high. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted September 29, 2018 Report Share Posted September 29, 2018 When anyone posts a cam or flat tappet failure due to lack of zinc in a Mopar flathead 6 cylinder engine I will stop asking this question. Small block shiverlay needs zinc. A Mopar flathead 6 cylinder does not. As I said document a failure if you can. 1 Quote Link to comment Share on other sites More sharing options...
NiftyFifty Posted September 29, 2018 Report Share Posted September 29, 2018 The catch is that most engines that require a cam when they get rebuilt are likely well beyond the signs of knowing if it was an oil failure and most likely it actually wasn’t because most of these trucks went out of service long before oil changed. Then we run into a lot of later built engines likely never seeing enough service to cause out in out failure. ZDDP is a pretty cheap insurance policy in protecting a vital part of the engine. I also don’t believe quality standards in oil are as tight as they should be, lots of times if you bought 10/30 Esso oil here in three different locations it was three different colours...cheaper it was the lighter it was 1 Quote Link to comment Share on other sites More sharing options...
ggdad1951 Posted October 3, 2018 Report Share Posted October 3, 2018 I use zrod oil Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.