Packard Forum Index » V-8 (1955-56)

for what it's worth, the engines without oil cleaners were designed so that the sludge could collect in the bottom of the pan, and dropping the pan and cleaning it out was supposed to be done yearly. For this scenario, non-detergent makes sense. Course lots of people didn't do that, so detergent oils are better for us lazy types who like to do tuneups every 60,000 miles.

I accidentally put some detergent oil in my 39 120 after years of non-detergent. Getting worried that the detergent oil was going to bust up some old sludge, I dropped the pan and cleaned it. Good news, it wasn't too bad. I refilled it with detergent multigrade oil and one quart of automatic transmission fluid. When I get about another 50 miles (total of 150 or so) I will drain it again and add detergent oil. The ATF seems to be doing a good job of freeing up the old lifters and gunk around the rings. In my opinion, as long as you change the oil once a year, regardless of mileage, you will be doing good things for your engine. If you are one of the adventurous types and drive a lot, I wouldn't go over 3000 miles before changing oil. Lots cheaper than overhauling engines.....

David's points are well taken. Today's motors burn cleaner which allows the oil to be used longer. Not changing the oil results in exhaustion of dispersants and detergency with subsequent deposits. Older cars need to follow more frequent intervals thus.

In diesel locomotive studies they found it didn't take long for neglect to damage those motors so a clean engine is indeed better off.

I was able to test out the straight 30 weight detergent oil in the heat today. A drive of several miles did indeed result in the engine oil light coming on. I stopped and added 15 oz. of STP, which I had along with the intention of adding to a warm, running engine (which circulates it best). The oil light stayed on for the rest of the drive, during which I never reached speeds over 40 mph.

I parked the car for a few hours at a friend's (my destination) and after that I drove it home, still in 85 degree+ temps. The oil light stayed off for the first few miles, started flickering, and then was on until speeds of about 50 mph were reached, at which time it flickered off.

Having been informed in an earlier post that Packard said this was "normal" in the straight 8, I didn't worry too much. There were no odd noises or fanfare.

I have decided that having the straight 40 wt that I had in before the last oil change was a better setup. Next change, I intend to put in 10w-40. This, based on the earlier post about better film strength with a multiweight.

Once again, if anyone has had good experience with a "conventional" 10w-40, I'd be interested to hear about it.

Thanks. This thread continues to be very helpful to me.

Uh, its only normal that the light should flicker at idle and the light should go out the instant the revs increase over an idle. It not remotely normal that the light should still be on at 40.

I hope it is that your oil pressure light switch is failing and not the oil pressure of the engine. Better screw an old mechanical gauge on there and see what you have really got.

One used to be able to buy oil pressure light switch sending units with varying pressure settings to trigger the warning light. Some triggered the light as low as 5 lbs or less and others up to 10 lbs or more. When we replaced failed units we opted for the highest setting available so as to give ample warning about low oil pressure, and we advised owners about the light coming on at idle.

(o{}o)

Early Sunday morning, while on my way to a car show the outside temperature was about seventy F. The trip is about 35 miles and all was quiet until I hit a long stretch of hill at about 45 mph. Lifter clatter started about mile 27 and resolved itself by mile 29 and all was quiet for the rest of the trip to the show. On the way home, temps had climbed to mid-80s and the clatter started about mile 15 after a mild hill climb. I pulled to the side and let it idle a bit because that has helped in the past but not this time. I turned off the engine and let it sit for about five minutes, hoping the misbehaving lifter might burp, but no dice. Eventually, I drove the clattering V-8 all the rest of the way home as gently as I could. I am running 20W-40 Valvoline with no additives, and running it about a half quart above Full per forum instructions. Later, once things had cooled a bit, no clatter. My Chrysler mechanic friend with a garage full of older Hemis and 440s, suggests using 20W-50 in summer months, just to see if that helps like it does with his MoPar motors..

My 374 was redone about five years ago (new rings, bearings, timing assembly but no oil pump) by the previous owner, another Chrysler mechanic. He also put in new equivalent Dodge truck lifters because of the clatter he had before the rebuild. Both of us have experienced it since, so I could presume that it's the oil pump/vacuum issue, but want to try something before changing over to the Olds solution and losing my vacuum wipers in the process.

Any harm in trying the overfilling of 20W-50 in summer driving? Reading some of the miracle cures on bottles a the parts store, I am also tempted there, too. The fact that this is the first time the noise did not resolve itself has concerned me. I want to do no harm.

DaveB845 Quote:

Solution: Olds oil pump & adapter. Fixes it permanently. Contact Jack Vines.

Craig

That is the exact symptom Packard highlights in its TSB about the camshaft thrust plate revision.

The TSB states lifter clatter at 45 mph.

Obviously they were groping given another TSB about the revised oil pressure regulator for the same symptom.

Once a lifter collapses while running it may not pump up again because it was damaged.

Whenever a motor is rebuilt the oil pump should be replaced if available. So I would replace the pump and probably the lifters.

Who knows the exact engineering defect causing this problem, but for the lifters to collapse the oil pressure in the gallery was falling below 10-15 psi. Given the vacuum pump delete has been successful that is the most likely suspect. Why it occurs at that specific situation is rather incongruous.

Quote:

Good advice, Ross. I don't think anything is hurting right now, but I just wonder about the oil pump pickup screen having some debris in it from running detergent oil.

The next oil change, coming up soon, will be done at the mechanic's garage, and I will ask them to remove the pan first and check the screen and the oil pan for gunk. Also, have them check the pressure with a mechanical gauge following the oil change, and some heated driving. I just purchased two 5-quart bottles of plain ol' PennzOil 10w-40, and will see how that sits with the straight eight.

As for hydraulic lifter clatter, etc., I don't have to deal with those, of course. I do realize that this is the V8 forum, but we can all stand to learn a little bit more about oil, can't we?

My most recent contribution to this thread has to be amended. I took the car for a short trip to the mechanic regarding the oil pressure light. He was nice enough to put it up on the hoist right away. The pressure sending switch was leaking badly. I will order a replacement, and all should be well when it's put in.

The fact that this coincided with an oil change is a mystery to me, except that it probably points out another instance of crud that was sealing a leak being cleaned out by detergent oil.

I still wonder about running a multi-weight next oil change. The mechanic cautioned against it, recommending straight 30 or 40, as the straight weights are better overall for high temps. That's what I thought, too, but I know there are other opinions.

Remember, this is for a straight eight with regular tappets, not a V8.