What oil for 1968 Mopar?

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Hey-
I have a '68 Barracuda Formula-S 340.
All original matching #'s. 123,000 on motor.
Want to change oil, but don't know what grade/weight to use.
I'm in Long Island,NY and car is stored for winter.
When I bought the car in May'07, the previous owner had just
changed oil...said he used Valvoline 10-40.
Car seems to be running fine, but I want to change oil before
taking out of storage.
If these ZDD claims are true, I want to use the correct oil/additive to match as closely as possible the oil that the motor required in'68 (so not to damage lifters, etc.)
Could you guys check out the site:
http://www.zddplus.com/index.htm
and help me decide what to do.
Seems like "modern" oil is not what I should use?

Thanks, Rick
 
I am the original owner of a 1968 Plymouth Roadrunner. 426 Hemi with 3 speed torqueflite auto. Engine and trans were both rebuilt last year. Engine was broken in with Valvoline VR-1 10W-30 and then changed to Mobil 1 10W-30. You might want to try the VR-1.
 
Alright, both of you need to show us some pictures if these jewels.

VR-1 10W-30 would be a good oil to use. Or, if you want to stay in the 40W family, Shell Rotella T or Delo 400.
 
I have had some old MOPARS and I have run Royal Purple. I have run Castrol GTX with excellent results as well but that was like SJ levels. RP oils should do the job for you. You could call their tech department and talk with them about it though to see what they say. I would avoid the newer SM grade oils myself in that application. I would run 10W-40 or even 20W-50.
 
Johnny- It is currently being painted. I will post picks when I get it back next week. It was a leftover. I bought it in Dec 1969 when I was 17. My dad would not loan me the money to buy it, said that I would kill myself driving the thing. Borrowed the money to buy it from my grandfather. 40 years is a long time to own a vehicle. Over the years I have been offered outrageous amounts of money for it. Almost sold it a couple of times,oddly enough it was my wife who would not part with it. During it's early life the only oil I used was Pennzoil racing oil 20W-40. The engine was just rebuilt by a friend of mine who was a mechanic for Holman Moody in Charlotte,N.C. Engine assembly lube was Mobil 1. I ran Valvoline VR-1 for breakin for 2000 miles than switched to Mobil 1 10W-30. This was per his recommendation. This thing is sweet. Puts out 590hp at the rear wheels on the dyno. I'll post picks next week. Thanks for the interest!
 
20.gif
Can't wait to see it.

Back in the day, Pennzoil GT Performance 20W-40 was one of the best oils you could buy. I used it and I was shocked when they discontinued it.

If your engine builder worked for Holman Moody and says to use Mobil 1 10W-30, then that is what I would use.
 
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Thanks, but this is original (never rebuilt) motor.
What did you use before rebuilt?
Also, mine is a stock 340.
 
What do you guys think about running a motorcycle oil in a older car? Walmart has Castrol 10w40 motorcycle oil that is SG/SH rated for only $2.69 QT. It should have much higher ZDDP or would this oil be bad to run in a car engine?
 
I would think Valvoline Maxlife 10-40 would be a great choice.

**If you think how much oil tech has changed since 1968, any oil today would be way better than those oils.
 
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I've always run either 10w30 passenger car oils (mainly Mobil 1 in recent years) or 5w40 HDEO (Rotella T synthetic) in my Mopars. I am NOT a fan of heavier oils like 10w40, 15w40, or God forbid 20w50 in old Mopars, provided they can hold normal oil pressures (minimum 40 PSI with the engine and oil fully hot at cruising speed, no lower than 10 psi engine and oil fully hot at idle.) Mopars oil the top end through the rocker shafts, not through the pushrods. Its an excellent system, better than through-the-pushrod oiling IMO, but it affects the whole system pressure and oil distribution differently. The holes in the #5 cam bearing only line up once per cam rotation to give a "shot" of oil to the rocker shaft on each bank. Too thick an oil will delay oiling to the top end too long, and unlike pushrod-oiled engines there's no excessive oil pressure bleed-off due to all the leakage in those types of systems (16 little leaks at the lifter, another 16 little leaks at the rocker, and then whatever is leftover finally gets where its supposed to go actually oils the rocker and the valve tip.) Both systems work, but IMO shaft rocker oiling likes thinner oil better.

And welcome to another Mopar guy! A 340 is one of the few Mopar engines I've never owned, but I'd sure love to. It gets my vote for the baddest smallblock ever- the ones I've ridden in pull like a big-block with a third less weight.
 
As I see it, you could either: continue with the conventional Valvoline, switch to Maxlife, or use a HDEO. Any of these should work fine. Personally, I would NOT switch to a full syn, as I'm not sure how well it would play with 41-year-old gaskets and seals. I'd use 10W30 or 10W40, depending on oil pressure.

Mopar to ya!
 
So it looks like Valvoline Maxlife 10w30 seems to be the choice.
No need to worry about the ZDD issue?

Thanks to all.
And thanks to 440Magnum for the welcome!

Will post pics of car ASAP.
 
Originally Posted By: 440Magnum
I've always run either 10w30 passenger car oils (mainly Mobil 1 in recent years) or 5w40 HDEO (Rotella T synthetic) in my Mopars. I am NOT a fan of heavier oils like 10w40, 15w40, or God forbid 20w50 in old Mopars, provided they can hold normal oil pressures (minimum 40 PSI with the engine and oil fully hot at cruising speed, no lower than 10 psi engine and oil fully hot at idle.) Mopars oil the top end through the rocker shafts, not through the pushrods. Its an excellent system, better than through-the-pushrod oiling IMO, but it affects the whole system pressure and oil distribution differently. The holes in the #5 cam bearing only line up once per cam rotation to give a "shot" of oil to the rocker shaft on each bank. Too thick an oil will delay oiling to the top end too long, and unlike pushrod-oiled engines there's no excessive oil pressure bleed-off due to all the leakage in those types of systems (16 little leaks at the lifter, another 16 little leaks at the rocker, and then whatever is leftover finally gets where its supposed to go actually oils the rocker and the valve tip.) Both systems work, but IMO shaft rocker oiling likes thinner oil better.

And welcome to another Mopar guy! A 340 is one of the few Mopar engines I've never owned, but I'd sure love to. It gets my vote for the baddest smallblock ever- the ones I've ridden in pull like a big-block with a third less weight.


Well, I have run 20W-50 in the following MOPAR engines from 65-76 wiith no issues...

318
340( actually my brother ran it in his 3 Darts - I never had a 340 )
360
383
440
 
Just spoke to tech. at Valvoline.
He suggests VR-1 (higher zinc).
Said he remembers (losing) to many Mopars, back in the day!
 
Just wanted to add my :2cents:

I have a 383 in my '68 Polara. I've been using HDEO 15W-40 for a couple of reasons. 1) the HDEOs have very strong add packs and can withstand fuel dilution very well. This tends to occur on carb'd engines often. 2) The HDEOs tend to have higher levels of ZDDP than standard passenger car SM rated oils.

I believe any 15W-40 will be ok such as Shell Rotella, Castrol Taction Extra, Chevron Delo, etc. They also tend to be pretty cheap in the gallon jugs. I know Rotella 10W-30 also is out there if you look for it.

I also usually don't drive the car in the winter mainly because of the salt but once it gets below freezing, I'm not comfy running the engine with a 15W in the sump.

I don't believe my engine was ever opened up so all of those seals are 40 years old. If everything was a fresh rebuild with modern seals/gaskets, I'd switch it to a HDEO synthetic such as Rotella 5W-40.

Ed B.
 
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