Engine Oil Recommendation

[B1Toad]

You can get Quaker State conventional in 10W-30 and 10W-40 at Walmart. I started using 10W-40 and it reduced my rear main leak to almost nothing. Quaker State is owned by Shell and is a good quality oil.

 

[MtPockets]

What brand, variety, and weight of engine oil do you recommend for the 4.0? Additional info: 240K miles, and cylinder 5 is burning oil. Thanks!

If you have been using dino oil, I'd stick with it. Synthetic can exasperate oil consumption.

Me? I'd go with good old Valvoline 10W40.

 

[BlueC]

But yeah I need everybit of protection to make myself feel better lol .... Edit- My LJ is at 258k miles

How many 4.0s do you know of with that mileage or more running a standard, low ZDDP oil? Run it if you want to, but the 4.0 was developed post cam/liter hardening and has a low spring pressure, so they do not need the extra ZDDP. Will it hurt, no, unless it starts getting into your exhaust.

10w30 Valvoline VR1 or 10w30 Rotella T6

I learned via oil samples to pick an oil type and stay with it. I keep VR1 on shelf for my old cars, and run Val synthetic in my modern vehicles (anything OBDII and newer). I used to have a habit of using either VR1 or the synthetic in my Jeep, or topping off that last qt with VR1 thinking the ZDDP would help. Well, a few oil analysis started showing elevated wear metals. A few weeks later The Oil Geek dropped a video explaining that different additive packages typically don't mix well and can "compete" with each other, specifically naming ZDDP and molly as two that will not mix well. I switched to Valvoline restore & protect and have stayed with it for the last 2 changes and wear has settled back down. That's why I suggest picking a flavor and sticking with it.

 

[D's Jeep Wrld]

How many 4.0s do you know of with that mileage or more running a standard, low ZDDP oil? Run it if you want to, but the 4.0 was developed post cam/liter hardening and has a low spring pressure, so they do not need the extra ZDDP. Will it hurt, no, unless it starts getting into your exhaust.



I learned via oil samples to pick an oil type and stay with it. I keep VR1 on shelf for my old cars, and run Val synthetic in my modern vehicles (anything OBDII and newer). I used to have a habit of using either VR1 or synthetic in my Jeep, or topping of that last qt with VR1 thinking the ZDDP would help. Well, a few oil analysis started showing elevated wear metals. A few weeks later The Oil Geek dropped a video explaining that different additive packages typically don't mix well and can "compete" with each other, specifically naming ZDDP and molly as two that will not mix well. I switched to Valvoline restore & protect and have stayed with it for the last 2 changes and wear has settled back down. That's why I suggest picking a flavor and sticking with it.

As mentioned my jeep seems to live at rev limiter,As well I'm running a bit more lift with the bigger cam I have so I'd like that ZDDP

Ive seen the video too,And he also mentioned that running too much zddp can also do more harm than good! And adding zddp to a synthetic oil can do bad
I primarily use Vr1 but I've had instances of needing to run Rotella t6 a few times since that's what I was able to get at any autoparts store since Ive realized I didn't have enough vr1 and I'm not waiting or making that drive to my local summit racing,So an oilchange with Rotella t6 does it
But yeah,you ain't wrong.