I recently bought my son a 1999 Jeep with the 4.0 six.Its due for a oil change it has 133k miles Ive read about the oil pressure gauge issue mine at start up is about 40 lbs and once warmed up its a about 10 to 15 lbs at idle and goes back to 40 under acceleration.What brand and weight of oil and filter do you guys recommend ? Thank you in advance
What brand and weight of oil and filter do you guys recommend?
- Thread starter mustangman2020
- Start date
Others will tell you to not use synthetic. I won't. Change it on schedule and dino oil is just fine...
Bas-NL
Member
my local 4x4 specialist garage uses 15W40 ( non synthetic ) and a mopar filter on al the TJ-s with a 4.0 six.
10-30 and wix filter. done it this way on all my jeeps with a 4.0
Napa ran a special a year ago on the Gold 1085, I think they were like half off. I ended up leaving with a case of them. Won't be needing to buy a filter anytime soon. I've been using Valvoline for oil
Napa ran a special a year ago on the Gold 1085, I think they were like half off. I ended up leaving with a case of them. Won't be needing to buy a filter anytime soon. I've been using Valvoline for oil
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Should be fine. Anything BUT Fram - or Penzoil anything. Some will stay away from Quaker State as well.
I'm a bit of an oil nut. I run used oil analysis on my vehicles to see how the engines are wearing and how the oil is performing. I also cut open the filters to see if there is junk inside and to see how well the filters held up.
The best wear numbers on a 4.0L I've had were with plain old Pennzoil conventional 10w30. The filters I run are Wix 51085, they have been the best constructed for the price that I have cut open. Napa Gold 1085 is also the same as the Wix, just with a different label.
The best wear numbers on a 4.0L I've had were with plain old Pennzoil conventional 10w30. The filters I run are Wix 51085, they have been the best constructed for the price that I have cut open. Napa Gold 1085 is also the same as the Wix, just with a different label.
I don't run Mopar anymore. They are built by Purolator filters, which used to be good but I cut open a few of them that had tears in the filter media.
I'm honestly shocked about the Penzoil. How was the "gunk" in the motor - back in the day, we could ALWAYS tell a "Penzoil motor" because of all the gunky slime deposited everywhere. Mayhap things have changed?
Agree about Wix/Napa filters.
I'm sure the mopar is fine, but I've always used Wix brand filters... Besides they're more convenient for me
Bas-NL
Member
i never had any problems with my TJ.and the owner of the garage has worked for more than 10 years for our Jeep importer in my country before he started his own business.
i trust on him
I've read on this forum a ton, lots of good info, but Mobil Super High Mileage Conventional (Dino-Dinosaur Oil, ha) 10w-30 is what I use for specific reasons in my 4.0 TJ based on good suggestions here, and any filter, I change every 3-3500 miles, so not sure it matters that much, but if others say they've seen good ones, for an extra $5 why not go with what they see
You can make Synthetic work, but I've seen it cause leaks, and the Mobil Super fix that, just my experience and what I've read (NOT always, but often enough I've read to be noticeable). For as often as I'm willing to change oil, I just don't see a need for synthetic, but that's a personal choice.
You can make Synthetic work, but I've seen it cause leaks, and the Mobil Super fix that, just my experience and what I've read (NOT always, but often enough I've read to be noticeable). For as often as I'm willing to change oil, I just don't see a need for synthetic, but that's a personal choice.
Not, It's Conventional Oil. Mobil Super High Mileage "Conventional" oil. I bought it on Amazon https://www.amazon.com/gp/product/B01GOWMJS8/?tag=wranglerorg-20
This is in the description:
"Seal conditioners rejuvenate aging engine seals to help stop and prevent oil leaks ".
04solartj
TJ Enthusiast
I am in the 10w-30 dino-oil and wix filter class room and like stated i change it every 3k miles but im old school... 
or is it just old?
p.s not a daily driver vehicle for me like many here
or is it just old?p.s not a daily driver vehicle for me like many here
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