1. #1
    zap2442's Avatar
    zap2442 is offline Junior Member
    Join Date
    Aug 2011
    Posts
    1

    What oil to use?

    hi i just bought a 1988 jeep wrangler yj with a reduily 4.2 l staight 6 engine... i was wondering what oil you use in yours

  2. #2
    TerryMason's Avatar
    TerryMason is offline Administrator
    Join Date
    Dec 1999
    Location
    Virginia Beach VA
    Posts
    6,143

    Re: What oil to use?

    Welcome to Jeepz.com

    I moved your post to the YJ forum - you should get more help here.

    I like Mobil 1 personally. The best thing to take some of your used engine oil at your next oil change and send it off for an engine oil analysis. Places like Blackstone labs are great for this.

    Here's a thread with more info
    http://www.jeepz.com/forum/cj-yj-tj-jk/33441-oil.html (Oil)

  3. #3
    amx4080's Avatar
    amx4080 is offline Junior Member
    Join Date
    Feb 2011
    Posts
    16

    Re: What oil to use?

    I'm a big fan of synthetic oils. Personally, I use Amsoil in all my vehicles.

  4. #4
    JohnnyO's Avatar
    JohnnyO is offline Senior Member
    Join Date
    Sep 2009
    Location
    Pittsburgh, PA
    Posts
    467

    Re: What oil to use?

    Jeep engines tend to throw off a lot of iron (in ppm, based on used oil analysis). Also older flat tappet engines are not entirely happy with newer oils that contain less zinc.
    If you live in a warm climate I would recommend a diesel-spec 15w-40 oil. In our Jeep I have Shell Rotella T5 10w-30 synthetic blend (diesel-spec) in it right now and will get a used oil analysis when it's time to change it.
    At the very least I would use high-mileage oil in a Jeep, even if it doesn't have high mileage. It's a little more stout and has somewhat more zinc than regular oil.
    Mobil 1 tends to show higher iron ppm in most engines although the oil itself holds up very well, and Jeep engines tend to show high iron regardless. If you want to use Mobil 1 then I would use the high-mileage version. I occasionally get used oil analysis done on my family's vehicles and I can say that in every case Pennzoil Platinum gave better results than Mobil 1 (not that Mobil 1 was bad).
    In a Jeep engine, especially an older one, I would advise either Rotella 10w-30 or Valvoline Max Life 10w-30 and change it every 3000 to 5000 miles.

    For used oil analysis: www.blackstone-labs.com, costs $25.
    Last edited by JohnnyO; 09-06-2011 at 09:41 PM.
    Steeler Nation does not have to travel. We're already there.
    '97 TJ 4-banger restoration project. My daughter's rig but I buy stuff and tinker with it.

  5. #5
    signguy's Avatar
    signguy is offline Member
    Join Date
    Oct 2010
    Location
    Tonasket WA
    Posts
    40

    Re: What oil to use?

    Johnnyo is absolutely correct. I use Shell Rotella T6 synthetic all year in my gas and diesel engines. Tests well and extends service intervals. By the way, buy cheap oil filters and you get what you pay for.

  6. #6
    JohnnyO's Avatar
    JohnnyO is offline Senior Member
    Join Date
    Sep 2009
    Location
    Pittsburgh, PA
    Posts
    467

    Re: What oil to use?

    True. I use Wix filters on the Jeep. I change the oil every 3000 miles, probably too often but my daughter is in college and does not put on a lot of miles, so that ends up being twice a year at most.
    Steeler Nation does not have to travel. We're already there.
    '97 TJ 4-banger restoration project. My daughter's rig but I buy stuff and tinker with it.

  7. #7
    Gotta-P's Avatar
    Gotta-P is offline Senior Member
    Join Date
    Jun 2011
    Location
    Atlanta, Georgia, United States
    Posts
    180

    Re: What oil to use?

    I only use pure synthetics and normally purchase what's on sale. I am more particular about the filter and tend to use Purolator or Wix.
    Paul...

  8. #8
    southtj's Avatar
    southtj is offline Official Supporter
    Join Date
    Aug 2003
    Location
    Memphis, TN
    Posts
    3,053

    Re: What oil to use?

    Whatever you use just be sure to to change it regularly. That is the key to long engine life.

  9. #9
    JohnnyO's Avatar
    JohnnyO is offline Senior Member
    Join Date
    Sep 2009
    Location
    Pittsburgh, PA
    Posts
    467

    Re: What oil to use?

    Here is the Used Oil Analysis I mentioned earlier (just got it back). You will see that the wear metals with Rotella were lower than with plain Pennzoil and that the lil ol' 2.5 just crushed the viscosity of the Pennzoil, probably from the high rpm.

    http://72.35.72.219/~library/15563/Jeep_UOA_11_2011.pdf
    Steeler Nation does not have to travel. We're already there.
    '97 TJ 4-banger restoration project. My daughter's rig but I buy stuff and tinker with it.

  10. #10
    amx4080's Avatar
    amx4080 is offline Junior Member
    Join Date
    Feb 2011
    Posts
    16

    Re: What oil to use?

    Why the jump up in calcium, phosphorus, zinc, etc.? Additives in the Rotella?

  11. #11
    JohnnyO's Avatar
    JohnnyO is offline Senior Member
    Join Date
    Sep 2009
    Location
    Pittsburgh, PA
    Posts
    467

    Re: What oil to use?

    Quote Originally Posted by amx4080 View Post
    Why the jump up in calcium, phosphorus, zinc, etc.? Additives in the Rotella?
    Probably, yeah. Different oils have different additive packages, especially Rotella since it is diesel-rated. Jeep engines tend to throw off a lot of iron anyway, so this bears out my theory that diesel motor oil is a good fit for Jeeps.
    Steeler Nation does not have to travel. We're already there.
    '97 TJ 4-banger restoration project. My daughter's rig but I buy stuff and tinker with it.

  12. #12
    amx4080's Avatar
    amx4080 is offline Junior Member
    Join Date
    Feb 2011
    Posts
    16

    Re: What oil to use?

    Quote Originally Posted by JohnnyO View Post
    Probably, yeah. Different oils have different additive packages, especially Rotella since it is diesel-rated. Jeep engines tend to throw off a lot of iron anyway, so this bears out my theory that diesel motor oil is a good fit for Jeeps.
    Makes sense it's the additives.

    This part of the post makes me wonder, since I'm also a Steelers fan. How come two Steelers fans are the only posters discussing chemistry? Here we go Steelers, here we go! (And in defiance to Hugh Hewitt, I can spell salmon! Anyone who listens to his radio show will get the joke.)

  13. #13
    signguy's Avatar
    signguy is offline Member
    Join Date
    Oct 2010
    Location
    Tonasket WA
    Posts
    40

    Re: What oil to use?

    The additional zinc in the Rotella T-6 Synthetic is the reason I use it on all my old engines. It is the missing ingredient in the newer motor oils. Do not use it on late model engines or an engine that leaks. I have also used this oil on a stationary diesel engine. I doubled my change interval and still got good test results.
    Signguy

  14. #14
    JohnnyO's Avatar
    JohnnyO is offline Senior Member
    Join Date
    Sep 2009
    Location
    Pittsburgh, PA
    Posts
    467

    Re: What oil to use?

    Quote Originally Posted by amx4080 View Post
    Makes sense it's the additives.

    This part of the post makes me wonder, since I'm also a Steelers fan. How come two Steelers fans are the only posters discussing chemistry? Here we go Steelers, here we go!
    Because Steelers fans are smarter than non-Steelers fans, obviously.

    www.steelernation.com

    My s/n is ronburgundy on the board.

    Checked the Jeep's oil today, it is still on the full mark with Max Life in it. I didn't check the miles but my daughter is in college and does not put on a lot. I will get a 3000 mile UOA on the Max Life also, if it is anywhere close to Rotella and consumes less, I will stick with Max Life. It worked for my mother's Cadillac which is an early-model oil-burning Northstar, although it does not have high mileage (a '99 with 63k).
    Last edited by JohnnyO; 11-20-2011 at 05:24 PM.
    Steeler Nation does not have to travel. We're already there.
    '97 TJ 4-banger restoration project. My daughter's rig but I buy stuff and tinker with it.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Log in

Log in