View Full Version : Lucas Vs. thick motor oil.
Motorhead350
08-25-2011, 10:59 AM
For the past year I have been feeding the car Lucas oil with 5w30 and it's keeping the engine alive and well. I was told by a member on here it turns 5w30 into 10w40. Wouldn't it just be easier if I put in 10w40 and forgot about the Lucas? It's cheaper that way too.
So again fill with 10w40 or just keep at it with the Lucas and 5w30?
My personal belief is to use the 5w30 and the Lucas upper cylinder lubricant.
I have proof the Lucas upper cylinder lubricant is NOT snake oil. Here in Florida, where you can only get the E10 gasoline I had an issue developing where the Marauder would lose a whole quart of oil between oil changes.
Just when the car turned 60,000 miles I began to use Lucas oil with each fill up of the E10 gasoline with the ratio being 3 oz of Lucas oil per 10 gallons of gasoline. The car is now getting ready to hit 68,000 miles and problem solved.
At least the last 3 or 4 oil changes, a full 6 quarts of oil drained out. It must of reconditioned some seals or valve guides but it WORKS! :D
fastblackmerc
08-25-2011, 11:36 AM
Use the recommended oil. Just like the owners manual says.
Use the recommended oil. Just like the owners manual says.
5w20 is only for fuel efficiency, for better protection 5w30 or 5w50.
massacre
08-25-2011, 12:28 PM
I've used Lucas in high-mileage 2Vs and it worked just fine.
Haven't used it in any 4Vs yet.
FWIW
prchrman
08-25-2011, 12:50 PM
5w20 is only for fuel efficiency, for better protection 5w30 or 5w50.
not so sure about that, many ford techs I have talked to said it is also precautionary for long hi rev situations. the thinner oil drains back quicker which in turn helps in eliminating cavitation at the oil pump and therefor losing pressure. forgot, we have tall heads which drain back slower than normal pushrod motors.
RacerX
08-25-2011, 01:00 PM
I thought cavitation was caused by the pickup tube mouth being too close to the oil pan bottom. Add a quart...;)
SC Cheesehead
08-25-2011, 07:43 PM
5w20 is only for fuel efficiency, for better protection 5w30 or 5w50.
Sez who?
Viscosity doesn't necessarily mean better lubication, especially in syn or semi-syn blends.
MOTOWN
08-25-2011, 07:44 PM
I would cringe at the thought of a 5w-50 start up on a cold day!
fastblackmerc
08-26-2011, 05:23 AM
I thought cavitation was caused by the pickup tube mouth being too close to the oil pan bottom. Add a quart...;)
I thought cavitation was caused by the crank dipping into the oil and "whipping" it up?
Phrog_gunner
08-26-2011, 05:25 AM
Sez who?
Sez the shade treez that know more than the team of people with engineering degrees that actually designed it.
sez who?
..........she!...........
Phrog_gunner
08-26-2011, 05:36 AM
I would cringe at the thought of a 5w-50 start up on a cold day!
A 5W start up on a cold day is a 5W startup, whether its 5W-20 or 5W-20000.
Heres a decent explanation:
http://www.upmpg.com/tech_articles/motoroil_viscosity/
SC Cheesehead
08-26-2011, 05:39 AM
Sez the shade treez that know more than the team of people with engineering degrees that actually designed it.
'zakly....
MOTOWN
08-26-2011, 06:02 AM
A 5W start up on a cold day is a 5W startup, whether its 5W-20 or 5W-20000.
Heres a decent explanation:
http://www.upmpg.com/tech_articles/motoroil_viscosity/
Not exactly bud! 5w-30 will drain back to the pan faster than 5w-50 on a cold day, and thats a fact!
Phrog_gunner
08-26-2011, 06:15 AM
Not exactly bud! 5w-30 will drain back to the pan faster than 5w-50 on a cold day, and thats a fact!
Except that the topic was a "cold start up", not warm oil drain back. Bud.
massacre
08-26-2011, 06:33 AM
I would cringe at the thought of a 5w-50 start up on a cold day!
Why?
5W-50 is the same when cold as 5W-20.
The first # is cold viscosity, the second # is hot viscosity..........
MOTOWN
08-26-2011, 06:53 AM
Familiar with sae oil ratings, ive always been a bit skeptical of multi weight oils(ability to thicken up/thin out) , but thats just me!
Phrog_gunner
08-26-2011, 07:02 AM
Familiar with sae oil ratings, ive always been a bit skeptical of multi weight oils(ability to thicken up/thin out) , but thats just me!
If I had a marker and a whiteboard, I could explain it to you in about 3.5 seconds with one graph. Your instincts are correct: 5 doesn't "thicken" into 30 when it heats up. On a graph where oil is thinning out due to warming up the Winter oils trend steady (don't thin out much) until they catch up with where the 30 oil has thinned out to at a certain temperature and then tend to follow the curve of the 30.
ctrlraven
08-26-2011, 12:03 PM
I would cringe at the thought of a 5w-50 start up on a cold day!
I run 15w-50 in my 89 5.0, sometimes I think I am putting molasses in instead of oil. lol
Motorhead350
08-26-2011, 01:24 PM
I love the tags.
You guys with a supercharger better think twice about running the anorexic 5W-20...
At high RPM and boost, the hydrodynamic wedge of oil between the bearings and crank can be completely squeezed out, causing metal to metal contact... Ford didn't spec 5W-50 for the GT for no reason at all...
I run Mobil1 0W-40 in mine and all is good...
BTW multi-viscosity oil do NOT thicken when hot, they just thin less than a straight weight...
Siege
08-27-2011, 10:42 AM
I came across these posts a while back on another forum:
I'm not going into details here, but I know I've talked to several people on this list before about this. Please do not put 5w-20 or less into a mod motor. Please.
That is all....
Gary-
I'm assuming you're not referring to my comments, or don't know my background? Are you aware that I spent about 10 years doing engine development with Ford Motor Company, including being the systems engineer on the 2003 Aviator and 2005 Mustang V8s?
5W-30 is probably a good oil for the street with mixed temperatures, yes.
I think you'll understand that I can go into details here. And understand that I'm not saying that 5W-20 is not going to instantly do damage. But suffice it to say I've seen and been involved in a LOT of development on these motors, and my personal opinion is that I would never run 5W-20 in a modular motor. Regarding your "spec oil" comment, you need to look at what else governs this recommendation.
I apologize for not being a little more clear and forthcoming.
Yes. I would not run 5W-20 in ANY stock mod motor. This is especially true in 4v motors, but applies to all of them in one form or another.
My *PERSONAL RECOMMENDATION* would be to run a good fresh synthetic in the 5w-30 to 10W-40 range. And keep an eye on oil temps and oil pressure variations. The oil viscosity might slightly change the VCT's transient behaviors, but I wouldn't expect significant issues. I admit that I've never tested or seen testing relating to oils thicker than 10W-40, so I can't comment on that.
Because I've seen the dyno testing. I've probably looked at several hundred engines disassembled and spread out on inspection tables. And I've been involved in testing to resolve issues where varying the oil viscosity was part of the test DOE. Trading a very small FE improvement in exchange for a large durability safety margin is not something I'm interested in doing.
The thread:
http://www.corner-carvers.com/forums/showthread.php?t=36607
I use 5W-30 in all the modular engines I've had.
MyBlackBeasts
08-29-2011, 10:01 PM
I would cringe at the thought of a 5w-50 start up on a cold day!
You would be ok. The "W" in 5W-20 stands for Winter. IE: when the oil is cold the viscosity flow is that of 5 weight oil - the 50 is the warm weight, meaning when the oil is hot it flows with viscosity of 50 weight. You would be correct in your original comment if the oil was Straight 50 (which would be 50w-50).
MyBlackBeasts
08-29-2011, 10:11 PM
Info should you be interested - One of the reasons they use the 5w20 is, these new engines are engineered with extremely close bearing tolerences. Thicker oils can't flow properly in these bearing applications and can cause 2 problems: oil starving as the bearing acts as a flow restriction to the oil system and actual no start/run problems, especially when the engine has low miles.
Info should you be interested - One of the reasons they use the 5w20 is, these new engines are engineered with extremely close bearing tolerences. Thicker oils can't flow properly in these bearing applications and can cause 2 problems: oil starving as the bearing acts as a flow restriction to the oil system and actual no start/run problems, especially when the engine has low miles.
So what is your recommendation?
Info should you be interested - One of the reasons they use the 5w20 is, these new engines are engineered with extremely close bearing tolerences. Thicker oils can't flow properly in these bearing applications and can cause 2 problems: oil starving as the bearing acts as a flow restriction to the oil system and actual no start/run problems, especially when the engine has low miles.
Oh boy another tighter tolerance... Tolerance means the variation allowed between too tight and too loose, or in other words more optimum clearances are achieved... If the engine could only use 5W-20 oil and something thicker would starve the bearings, there would be severe oil starvation when the engine was cold and oil was 15-20 times thicker than at operating temps...
na svt
08-30-2011, 11:05 AM
Oil threads hurt my head.
Black&Gifted
08-30-2011, 01:14 PM
You guys with a supercharger better think twice about running the anorexic 5W-20...
Really? Why? I guess it is a matter of opinion but I ran 5/20 in supercharged vehicles for MANY MANY rapped ape miles.
At high RPM and boost, the hydrodynamic wedge of oil between the bearings and crank can be completely squeezed out, causing metal to metal contact... Ford didn't spec 5W-50 for the GT for no reason at all...
What oil did Ford spec for the Terminators, Gen 2 Lightnings and 02-03 Harleys? 5/20. Correct me if I am wrong, but all of those vehicle metioned above are FACTORY supercharged vehicles. Many of the owners of those vehicles still run that weight oil at much more boost and RWHP levels than stock. Also, I don't understand the analogy to the Ford GT. The only thing taken from that is Ford recommended a different oil for a SPECIALTY HIGH END VEHICLE, rather than a car marketed to the general public. If Porsche recommended a different weight oil in their Carerra GT but a different weight in the 911 turbo (assuming they did, which I don't know if they do), would you doubt which oil to use in your Porsche? This could go on and on...
Do I have an engineering degree? No. Am I a mechanic or chemist or some supersmart nerdy dude who has all the answers? No. Just know what I do from experience with breaking supercharged mod motors.
Like I said off right off the bat, it is a matter of opinion. At the end of the day, I want to punch myself in the face.
Use your 5W-20 if it suits you... The US market is the only one that recommends 5W-20(can you say CAFE???), the same engines in Australia, Middle East, etc use 5W-30/40 or 10W-30/40...
The second gen Lightnings were originally specked with 5W-30, Ford did back spec the pre '01 models to 5W-20...
You didn't explain how these engines don't starve for oil when cold and oil is in the range of 1500%-2000% thicker than when hot... The oil 0W-40 Mobil 1 I'm using is thinner than the 5W-20 when cold and roughly 75% thicker when hot... At 100*C(temp oil weights are rated)even a 40W oil isn't exactly thick...
Black&Gifted
08-31-2011, 08:06 AM
:poke:Good point re climate. None of my previous supercharged vehicles were driven in weather less than 50*.
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