Oil Grade for a 1973 CJ5 (3.8)
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Oil Grade for a 1973 CJ5 (3.8)
- Thread starter Jmullennix90
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Hedgehog
Always Off-Roading Jeeper
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- -1975 Jeep CJ5, 360 V8, Headers, Duel Exhaust,T15 transmission, D-20 Transfer case, Twin Stick Conversion, Warn 8274 Winch
-1951 Willys Wagon, 4 cylinder, "F" head, little rust, very close to stock
For older engines I am a believer in the "Brad Penn" line of oils. As far as grade is concerned it really depends on your belief in what an oil is there for. The believers in light grade oils like to have their oil move quickly through the oil system. Fast moving oil also takes more heat along with it. The thick oil crowd, which I'm a part of, likes the idea of a relatively slow moving thick oil that holds up (stays oily) to heat making the best buffer against wear possible. Really it's up to you to decide, all oil does it's job well.
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- '85 CJ-7, 258/4.2L 6cyl. Bought new in 1985. Full cage, Warn 8274 winch, Ford 9" rear, front/rear Detroit Lockers w/4:88 R&P. T-5 tranny and 4:1 t'case. 33X12.50-15 BFG/AT, MSD ign, on board air---
WELCOME 
You would do fine with either 15W-40 or 20W-50(what I have used for 30 yrs in my Jeep).
LG
You would do fine with either 15W-40 or 20W-50(what I have used for 30 yrs in my Jeep).
LG
steve1973
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I'm in the thin oil crowd. I run 5w-20 In my 73 with the AMC 258 i6 / 4.2l year round.
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- Vehicle(s)
- '85 CJ-7, 258/4.2L 6cyl. Bought new in 1985. Full cage, Warn 8274 winch, Ford 9" rear, front/rear Detroit Lockers w/4:88 R&P. T-5 tranny and 4:1 t'case. 33X12.50-15 BFG/AT, MSD ign, on board air---
With the winters you see. Not a bad choice.
The OP is in Oceanside Ca. near San Diego.
Remember that those old AMC engines were built abit on the 'loose' side.
LG
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I run the thicker oils in summer and the thinner ones in winter.
I run Lucas "Magnum" 15w-40 DIESEL engine oil in my AMC 258 i6 / 4.2l . Since my Daily Driver is a 1990 Dodge Cummins, I run the Lucas (or Rotella in a pinch) in both. Easier to just keep one type of oil around
- Posts
- 14,790
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- 55
- Location
- Springfield, Missouri-U.S.A. Earth
- Vehicle(s)
- '85 CJ-7, 258/4.2L 6cyl. Bought new in 1985. Full cage, Warn 8274 winch, Ford 9" rear, front/rear Detroit Lockers w/4:88 R&P. T-5 tranny and 4:1 t'case. 33X12.50-15 BFG/AT, MSD ign, on board air---
Lucas oil additive is a joke-GOGGLE search will prove that.
I've been run'n STP(blue bottle)in my Jeep for over 30 years.
Have 120K miles on the un-rebuilt engine, and still shows 55psi hot oil pressure on the f'way.
LG
I've been run'n STP(blue bottle)in my Jeep for over 30 years.
Have 120K miles on the un-rebuilt engine, and still shows 55psi hot oil pressure on the f'way.
LG
Not sure who was speaking for lucas oil additive. I'm referring to their line of diesel engine oil. What makes you say that their additive is a joke? It does it's job rather well, which is primarily boils down to a thickener, more or less, like motor honey. Not looking to start a fight, just want to hear your input
EDIT:Not saying motor honey is a good product, but I fail to see how it or the Lucas additive could hurt anything
Hedgehog
Always Off-Roading Jeeper
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- 9,370
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- Location
- Tucson/Marana Arizona
- Vehicle(s)
- -1975 Jeep CJ5, 360 V8, Headers, Duel Exhaust,T15 transmission, D-20 Transfer case, Twin Stick Conversion, Warn 8274 Winch
-1951 Willys Wagon, 4 cylinder, "F" head, little rust, very close to stock
I'm a little interested too. Lucas oil products have always seemed right to me.
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- Springfield, Missouri-U.S.A. Earth
- Vehicle(s)
- '85 CJ-7, 258/4.2L 6cyl. Bought new in 1985. Full cage, Warn 8274 winch, Ford 9" rear, front/rear Detroit Lockers w/4:88 R&P. T-5 tranny and 4:1 t'case. 33X12.50-15 BFG/AT, MSD ign, on board air---
I'm still look'n for the other tests I've read. Sometimes, my search 'foo' sucs
Here's one to start with-
http://cdn2.hubspot.net/hub/68152/f...bell_performance_xtra_lube_four_ball_0709.pdf
LG
Here's one to start with-
http://cdn2.hubspot.net/hub/68152/f...bell_performance_xtra_lube_four_ball_0709.pdf
LG
I take this comparison with a grain of salt, all I see is an endorsement for the Bell product. Perhaps I would value it more if it was an independent study. They also used the product inconsistent with it's labelling. No one is going to use straight additive as their crankcase lube (I hope). I don't disrespect your opinion, everyone has their own, however I have to disagree with this experiment as being credibleI'm still look'n for the other tests I've read. Sometimes, my search 'foo' sucs
Here's one to start with-
http://cdn2.hubspot.net/hub/68152/f...bell_performance_xtra_lube_four_ball_0709.pdf
LG