Oil Changes on older cars

i seen at walmart they now carry sj rated castol 20w/50 for order cars

CASTROL GTX CLASSIC | WELCOME | CASTROL USA
I always liked Castrol. My highschool science teacher had a late 70's Chrysler that he drove every day and had over 300,000 miles at the time. He had mentioned a few times about Castrol GTX and keeping up on maintenance. I recently learned about GTX classic and I used it for my last oil change. I won't know for years if it makes a difference though. Would be nice if they started offering different weights.
 
ALL of the old rubberized cork or pure cork gaskets which seal oily fluids will eventually start to seep, by observation. Some dino oils have more thinner components in them than others do, which relates to the brand of the motor oil, not specifically that it's dino or syn. Which is why some brands of oils would cause valve cover gasket leaks in engines and others were less prone to leak, by observation. Might have also had something to do with the viscosity of the oil, too?

My late machine shop operative noted that you wanted a motor oil that might cause oil leaks. The thinner factions of the oil were getting places that other oils might not get, he noted. Which is why his old pickup truck would have a valve cover gasket leak with one brand of motor oil and when he changed to another brand, that leak would dry up. He bought whatever oil was on sale at the local auto supply, one case at a time, back then.

Once the oil wicking action into and through the cork-material gaskets starts, it might be slowed a bit by tightening the hold-down bolts more, but most probably not. Which is why valve covers almost always have indentions under the hold down bolt heads!

At one time, some claimed that the syn oils would compromise rubber lip seals in the engine. As in timing cover front crankshaft seals. I'm not sure that was universally true, though, although at one time, Valvoline recommended their syn oils for engines built after 1975 or so, which I read on one of their old oil bottles in the 1990s. Many people have changed to syn oil in their older engines with no issues, though. I don't know that I would put it in an older engine with lots of sludge and gunk in it though, but if that engine had been rebuilt, THEN it might be a good decision. Several variables to consider.

Enjoy!
CBODY67
i oused 20w50 with a zinc additive no leaks the only one i had a rocercove the felpor gaskers was junk i only use veictor rines now
no leaks
 
I use 10/30 Valvoline Conventional and Rislone Zinc additive.

rislone-zinc-zddp-e1443532059691.png
 
10w30 is too light for me i have allways used Valvoline 20w50 i used it in my 400 that i raced for 12 yrs & drove it as a dayly driver too (I shifted at 6000 -6500 rpm in 1st gear
Yep, I have a couple of street engines. No need for thick oil.
 
Here’s my “2 cents” on the subject: I found REV X ZDDP additive on Amazon, 5 bottles for about $40 and use SuperTech synthetic from Walmart. Amsoil also offers their Z-ROD product which is a full synthetic with added zinc for older vehicles. Or, if a roller cam is available for your engine, that would eliminate the need for the zinc. No matter what, progress seems to cost us all more money.
 
When my ordered '77 Camaro came in in 05/77, I did the first oil change at 3000 miles. Went with Castrol GTX 20W-50 and oil consumption was 1/2 qt/4000 miles. Somewhere along the way, like at 250K miles, it was 1qt/4000 miles. As things progressed, the oil was still pretty clear, so I would put a quart in it and run it until it was 1 qt low again before I'd change it. At that time, I was doing my own oil/filter changes. Upgraded to Castrol Semi-Syn 10W-40 later on, then to Rotella T 5W-40.

When we finally put in a pre-built 355, the intial oil was the engine installer's choice, Valvoline 30W. After about 3000 miles, I changed it back to Castrol 20W-50. I immediately noticed that throttle response and pwoer were just a bit down, so I changed it to 10W-40 and those things came back like they used to be with the 30 oil in it. Lesson? As reported, the thicker viscosity oils do consume more power, just a tad, but enough for me to notice. Later, went to Rotella syn 5W-40 for the zddp content.

Ended up putting 625K on that old 305. Pulled it out as all of the block freeze plugs were seeping. Figured that IF I could get a Chevy motor to last that long, a MOPAR would be forever. One "assist" was the Cloyes Plus-Roller timing chain at 92K miles.

As things have progressed, a quality rebuild with quality machine work at or near min-spec clearances, OEM-quality gaskets, with quality syn motor oil (probably 10W-30 or 5W-40), a good oil filter, and ANY Chrysler V-8 should easily out-last your wildest suspicions of longevity. Proving the integrity of the original design and execution, to me.

Just some thoughts and experiences,
CBODY67
 
Yep, I have a couple of street engines. No need for thick oil.
20w50 isnt thivk oil i use it imn my weekend driver i drive it to shows sometimes 3-400 miles to shpows now i did rebuiile it my self it has all new parts in it , but even after i bought it i used the same oil in it .
10w30 is too thin/light of oil for me ,its my choose i change every 2-3000 mies then i use a mopr oil filter i by from walmart
 
I'm not a fan of using additives in my oil.

I think most of it is snake oil and if you're lucky, it won't hurt anything. Using some common sense, I can say that I have no idea if the additive is actually mixing with the oil or just settling in the pan. The only thing that tells you IF the additive will work is what you read on the side of the bottle.

Makes zero sense to me to use an additive that may or may not work when oils formulated to do the job are readily available.
 
When my ordered '77 Camaro came in in 05/77, I did the first oil change at 3000 miles.
....

When we finally put in a pre-built 355, the intial oil was the engine installer's choice, Valvoline 30W. After about 3000 miles, I changed it back to Castrol 20W-50. I immediately noticed that throttle response and pwoer were just a bit down, so I changed it to 10W-40 and those things came back like they used to be with the 30 oil in it. Lesson? As reported, the thicker viscosity oils do consume more power, just a tad, but enough for me to notice. Later, went to Rotella syn 5W-40 for the zddp content.

....

As things have progressed, a quality rebuild with quality machine work at or near min-spec clearances, OEM-quality gaskets, with quality syn motor oil (probably 10W-30 or 5W-40), a good oil filter, and ANY Chrysler V-8 should easily out-last your wildest suspicions of longevity. Proving the integrity of the original design and execution, to me.

CBODY67

My own experience after running Mathilda the first year with 10W-40 Valvoline was that I had to prime the oil pump with Vaseline after oil changes, and I had plenty lifter noise from something on the passenger side. (I suspect cyl. 6) So, I started running Motorcraft Diesel motor oil 10W-30 and have had a quiet, smooth running engine which no longer needed any chicken-ritual after oil-changing. I also switched from the much hyped K & N oil filter to WIX, resulting in visibly cleaner oil for months.
 
My own experience after running Mathilda the first year with 10W-40 Valvoline was that I had to prime the oil pump with Vaseline after oil changes, and I had plenty lifter noise from something on the passenger side. (I suspect cyl. 6) So, I started running Motorcraft Diesel motor oil 10W-30 and have had a quiet, smooth running engine which no longer needed any chicken-ritual after oil-changing. I also switched from the much hyped K & N oil filter to WIX, resulting in visibly cleaner oil for months.
i aolnly iuded a mopr filter &S allwaysused 20w50 from when i bought her till now with lucus zinc additinve but im switchbg evrry othr oil change between the rotellsa &S the 20w50 it is quite as can be
noyw my coudin used 10w40 valivolin with no addituves
but he had to rebuold the bb 1 time allready
 
i aolnly iuded a mopr filter &S allwaysused 20w50 from when i bought her till now with lucus zinc additinve but im switchbg evrry othr oil change between the rotellsa &S the 20w50 it is quite as can be
noyw my coudin used 10w40 valivolin with no addituves
but he had to rebuold the bb 1 time allready

I admit to using Rotella T5 10W-30 that first post-K&N year, but the most recent data I found on ZDDP showed Motorcraft's mixture at 1220 ppm, w Rotella down to ~950 ppm. I likely would use a mild ZDDP supplement if all I had was Rotella T5/6 for an oil change, though I would caution folks that the Lucas stuff is best reserved for cam break-ins.
 
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I use 10/30 Valvoline Conventional and Rislone Zinc additive.

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This is the only ZDDP supplement I would use with an oil change and have! It's Good Stuff. I don't use it with the Motorcraft diesel motor oil, as it suffices in ZDDP on its own. I like Valvoline's racing oil also, but I find very few stores where I can walk in and buy their 10W-30 offering unless I order in advance. I've contemplated going to Penngrade also. Time and budget will tell.....
 
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This is the only ZDDP supplement I would use with an oil change and have! It's Good Stuff. Idon't use it with the Motorcraft diesel motor oil, as it suffices in ZDDP on its own. I like Valvoline's racing oil also, but I find very few stores where I can walk in and buy their 10W-30 offering unless I order in advance. I've contemplated going to Penngrade also. Time and budget will tell.....

I use that Rislone stuff too. Allows me to be flexible with my oil brands but still always have zinc
 
I use Rotella 5/40 in a VW 1.4, Cummins 5.9, BMW M57 and of course the Chrysler's 440. Been that way many years.
 
I use Rotella 5/40 in a VW 1.4, Cummins 5.9, BMW M57 and of course the Chrysler's 440. Been that way many years.

The last PQIA report I saw on Rotella T6 shows zinc at 1310 ppm! Good stuff, IFF this figure from 2014 still holds.
 
i called them &S talked the the head engineer incharge of mixing it has a min of 1200 ppm of zinc the adverage is 1310 ppm

12-1300 ppm Zn works well enough for most folks flat tappets, for sure. I've been cruising w Motorcraft's diesel motor oil @ 1206 ppm Zn for 3 yrs, but just upgraded to Lucas Hot Rod & Classic oil with 2100 ppm Zn! THAT's a LOT of zinc! I shan't consider any further additives such as Rislone's with a healthy amount like this. I think Valvoline's VR1 is higher, and Penngrade, Wolf's head and Kendall all contend but most motor oils with any zinc nowadaze only permit amounts in solution > 1000 ppm if for diesel engines or the racetrack.

Of course the Ruling Pigs really just lust to grab ALL our iron, rolling, cutting and/or shooting, stick us in wattle & daub huts, then murder who they hate the most on a given day. FEW of the lemmings get this Ugly Truth.....
 
My choice for classic cars has always been Valvoline 10w30 conventional grade w/ Lucas zinc additive. Modern cars Valvoline Synthetic 5w30.
 
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