5W-50 oil in 500 CI (1970 Eldorado) ?
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Page 1 of 4 1 2 3 4 LastLast
Results 1 to 15 of 51
Like Tree3Likes
Cadillac Seville / Cadillac Eldorado Forum Discussion, 5W-50 oil in 500 CI (1970 Eldorado) ? in Past Cadillac Vehicle Discussion; Is it advisable to use 5W-50 in a 500 CI motor? Motorcraft makes one. The original manual for the 1970 ...
  1. #1
    sgc2c is offline Cadillac Owners Member
    Automobile(s): 1970 Cadillac Eldorado 62k
    Join Date
    Jan 2008
    Location
    Boca Raton FL
    Posts
    45

    5W-50 oil in 500 CI (1970 Eldorado) ?

    Is it advisable to use 5W-50 in a 500 CI motor?
    Motorcraft makes one.
    The original manual for the 1970 Eldorado claims
    a wide variety of oils from 5W-20 up to 20W-40
    can be used. Engine has 63,000 miles on and it,
    understandably, leaks basically every fluid you
    can put in it.

    can

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    MoistCabbage's Avatar
    MoistCabbage is offline Cadillac Owners 10000+ Posts
    Automobile(s): Crimson 2001 Seville STS, 1990 Seville (RIP)
    Join Date
    Sep 2010
    Location
    East Boston MA.
    Age
    26
    Posts
    21,902
    Well according to the range listed in the owners manual, 5W-50 is too thick at operating temperature. Use whatever viscosity is recommended for your local climate.

  4. #3
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    73,821

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    I would say 5W50 is TOO low on the low end and TOO high on the high end. I'd stick with 10W30 or 10W40, preferably 10W30.

  5. #4
    Submariner409's Avatar
    Submariner409 is offline If it won't run, chrome it
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    45,001

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    Many large displacement gasoline engines, particularly flat-tappet cammed engines subjected to heavy duty use, successfully run a "fleet" oil such as Pennzoil LongLife 15W-40.

  6. #5
    Aztec ETC ECS's Avatar
    Aztec ETC ECS is offline Cadillac Owners Connoisseur
    Automobile(s): '02 ETC ECS#533, '05 Escalade, '05 AWD Magnum, '74 455 OLDS
    Join Date
    Feb 2012
    Location
    NYC
    Age
    47
    Posts
    1,898

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    5W-50 is a 50 weight oil that flows like a 5 weight oil when cold. W is for winter, which you will never see in FL.
    I always used & will always use 20W-50 in my Olds 455.

  7. #6
    Submariner409's Avatar
    Submariner409 is offline If it won't run, chrome it
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    45,001

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    Why 20W-50 ?

    We use exclusively 15W-40 in these Olds 455's and GM 454's in extreme duty boat applications and have not had any sort of lube oil problems. We run Melling HD pumps at 60 psi, oil temp 210 degrees, Fram HP-2 filters, roller tip rockers, flat tappet cams (Engle).

    20W-50 is a motorcycle (air cooled) lubricant - not even recommended by Caterpillar or Cummins for diesel service.

  8. #7
    Aztec ETC ECS's Avatar
    Aztec ETC ECS is offline Cadillac Owners Connoisseur
    Automobile(s): '02 ETC ECS#533, '05 Escalade, '05 AWD Magnum, '74 455 OLDS
    Join Date
    Feb 2012
    Location
    NYC
    Age
    47
    Posts
    1,898

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    True, it is considered a motorcycle oil, but as far as I've always heard it's also a racing oil.
    Works for me. Bottom end has been in the car for 10+ years with approx 600HP & lbs.ft.



    I also run an Engle (solid) cam w/Erson Pontiac roller rockers (1.65 vs 1.6) & fully ported C heads.
    I also got better results from a single plain Torker.

    I have noticed Rotella 15w40 seems thicker while pouring out of the bottle than 20w50. Imagination?

  9. #8
    Submariner409's Avatar
    Submariner409 is offline If it won't run, chrome it
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    45,001

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    Darned if I know - both Rotella and LongLife (both 15W-40) are spec'd as a fleet (gasoline), diesel and marine oil. It carries a pretty heavy ZDDP load, so you don't want to run it in a cat car. I run either about 100 hours in boat engines before change - that's equivalent to 6,000 to 7,000 miles of car service. The local Western Auto carries it in 5 quart jugs and 5 gallon pails. I get the HP-2 filters in bulk from Fram.

    My Olds engines use the Milodon 8 quart pans with windage tray and I rig a remote oil change line from the (permanently installed) oil drain plug - a HD length of flex oil line to a ball valve with hose barb. Oil change time comes, warm up the oil, open the ball valve, connect a drill pump, and pump it all into a big bucket.

    Here's a pic of an HP-2 compared to a 51522 ........... The HP-2 holds just about one quart of oil and has a case burst strength of 250 psi. Anti-drainback.

    Here's a trick for your next 455 - The snaky cover over the cam in the valley. Clean it well and drop it in place. Mark the center of each lobe with a magic marker dot. Now drill a 3/32" hole at each dot and chamfer that with a 1/4" drill tip. That cover now catches oil drainback and drips it onto each cam lobe. Looks like a Mondello splash shield. I use the dual-plane Performer 2151 - work boats get a lot of idling time so they need some carb heat - so I drill 1/2" holes in the intake manifold gaskets at the crossover ports. The engine I posted went into my boat - notice the cylinder head color - they're Mondello street-ported Ga heads. (What valve rotators ??? )

    (Sorry for the thread hijack, but there are tidbits of good info in these posts - for ANY gearhead.)(and, FWIW, Shell Oil owns Shell, Pennzoil, and Quaker State. SOPUS - Shell Oil Products U.S. - read the labels.)

  10. #9
    Aztec ETC ECS's Avatar
    Aztec ETC ECS is offline Cadillac Owners Connoisseur
    Automobile(s): '02 ETC ECS#533, '05 Escalade, '05 AWD Magnum, '74 455 OLDS
    Join Date
    Feb 2012
    Location
    NYC
    Age
    47
    Posts
    1,898

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    Quote Originally Posted by Submariner409 View Post
    Here's a trick for your next 455 - The snaky cover over the cam in the valley. Clean it well and drop it in place. Mark the center of each lobe with a magic marker dot. Now drill a 3/32" hole at each dot and chamfer that with a 1/4" drill tip.
    It's back together now, but next time it's apart, I'll try it.

  11. #10
    sgc2c is offline Cadillac Owners Member
    Automobile(s): 1970 Cadillac Eldorado 62k
    Join Date
    Jan 2008
    Location
    Boca Raton FL
    Posts
    45
    Back to my original question, is 5W-50 too
    extreme for Florida? I'd think the 50 weight
    would be ideal in the heat for such a large
    engine and the 5 weight is already approved
    in the manual, ideal for cold starts, however
    few those are here.
    If you favor 10W-40 or 10W-30 then which,
    and why?

  12. #11
    Submariner409's Avatar
    Submariner409 is offline If it won't run, chrome it
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    45,001

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    What makes you think that the internal engine temperature - the parts not cooled by coolant: the parts cooled by oil - will be any higher in Florida than in anywhere else on earth ?? Just because the engine is of large displacement does not mean that it needs "thicker" oils.

    There is absolutely no need to run a 50 weight oil, regardless of leaks. If you're antsy for some reason that a -20 or -30 oil is not "oily" enough, then run 10W-40 or maybe a 15W-40.

    It's a 44 year old engine with no mileage - it isn't even broken in yet. Why force the bearings to wear out to clearances wide enough to accommodate a 50 weight ? 63,000 miles comes out to < 1500 miles per year. The engine doesn't even know how to run !

  13. #12
    Aztec ETC ECS's Avatar
    Aztec ETC ECS is offline Cadillac Owners Connoisseur
    Automobile(s): '02 ETC ECS#533, '05 Escalade, '05 AWD Magnum, '74 455 OLDS
    Join Date
    Feb 2012
    Location
    NYC
    Age
    47
    Posts
    1,898

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    Yeah, 10 or 15w 40 will be fine.
    Not that I believe the 5w50 would do any harm though.

  14. #13
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    73,821

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    Quote Originally Posted by sgc2c View Post
    If you favor 10W-40 or 10W-30 then which, and why?
    10W30 gets my vote. Should be fine for Fla. I don't like 10W40. I used that stuff back in the '80's and had to replace 2 lifters and a cam on a 302 Ford. "Sludge" wouldn't describe it. I had to scrap the oil out of the valve covers and the timing chain cover with a putty knife. I still have a bad taste left in my mouth from that. Never saw anything like it, before or since. I know oils are much better now, but I just can't bring myself to even consider using it.

    Oh, and before anyone asks, the oil was changed every 3K from day one.

  15. #14
    Aztec ETC ECS's Avatar
    Aztec ETC ECS is offline Cadillac Owners Connoisseur
    Automobile(s): '02 ETC ECS#533, '05 Escalade, '05 AWD Magnum, '74 455 OLDS
    Join Date
    Feb 2012
    Location
    NYC
    Age
    47
    Posts
    1,898

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    I saw lots of sludgy engines in the 80's. Was it the thickness or the quality?

  16. #15
    Submariner409's Avatar
    Submariner409 is offline If it won't run, chrome it
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    45,001

    Re: 5W-50 oil in 500 CI (1970 Eldorado) ?

    80's engines ? Neglect.......... of either oil changes or the PCV system .............. and some of the Japanese product had LOUSY PCV systems. Back in the Dark Ages engines were internally vented by a "road draft tube" which simply dripped oil vapor from the crankcase out onto the road - the reason that all roads used to have a black stripe down the center of each lane. Advances in PCV changed all that - and removed most of the causes of "sludge": crankcase moisture.

    If oil "thickness" had anything to do with "sludge", what would the inside of an aircraft recip engine - running 50, 60, or 80 single grade - look like ??? Or the inside of a 35,000 hp marine diesel engine, max rpm of 120, running 80W oil ???

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting