05 wrangler 4.0 oil recommendations

[02s4audi]

I'm purchasing a 2005 jeep wrangler tomorrow. It has the 4.0 inline 6 and 132k miles on it. Im wondering what oil you guys recommend for this engine? I will run a fram ultra filter with whatever oil I run. I live in upstate NY and would like an oil i can stick with all year round. Thanks

 

[02s4audi]

I was thinking maybe rotella t6 as I thought I read somewhere that people loved it in the jeep 4.0 I was also wondering about m1 0w40

 

[Kuato]

The 4.0 does like 5w40 Rotella, and also 10w30s. I had the 4.0 in two different Grand Cherokees and used 5w30 - also with good results. Avoid M1 oil in this engine as it produces more than twice the iron as other oils. I miss my 4.0; oil changes are extremely straightforward.

 

[Chris142]

No oil will stop the 05 and 06 from eating the oil pump driveshaft and the cam gear. I would stay away from those 2 years.

 

[02s4audi]

I'm leaning towards t6. Seems like people use it in everything lol.

 

[TheKracken]

I didnt know they had the inline 6 all the way to the 05 year...might just have to consider one of those, they are legendary from what I hear,

 

[DdDd]

I did 150k miles on that motor in the TJ using nothing fancier than M1 5w-30 changed every year or 10k miles, whichever came first. Filter I used was one size up PH8 in fram I believe. The one that fits the old ford 5.0. It held more oil than the stocker and had more filter. When the engine finally croaked it was a head gasket leak that did it in. Sudden coolant loss out the cylinders lol. When the mechanic was looking at it he was astounded how new the internals and hatching looked. No ridges or sludge. Only goes to show, worry about oil until you're blue in the face. Any number of things can get you. Yes they had a defective head casting in those early 2000 models. Id check the stamping if I were you. Google the problems...

 

[Kuato]

Originally Posted By: DdDd

I did 150k miles on that motor in the TJ using nothing fancier than M1 5w-30 changed every year or 10k miles, whichever came first. Filter I used was one size up PH8 in fram I believe. The one that fits the old ford 5.0. It held more oil than the stocker and had more filter. When the engine finally croaked it was a head gasket leak that did it in. Sudden coolant loss out the cylinders lol. When the mechanic was looking at it he was astounded how new the internals and hatching looked. No ridges or sludge. Only goes to show, worry about oil until you're blue in the face. Any number of things can get you. Yes they had a defective head casting in those early 2000 models. Id check the stamping if I were you. Google the problems...

0331 head issue was solved by 2001 so not an issue for OP in his '05. While M1 is a very good oil, I'll say again that it's well documented that M1 produces more than twice the iron wear in this engine.

 

[ChrisD46]

*Regarding M1 high iron levels : Wasn't that just one year due to a hurricane causing the need for a temp formulation change ?

 

[02s4audi]

They used the inline 6 up until 2006. In 2007 new body style (jk) with a 3.8 v6

 

[jeepman3071]

Pennzoil conventional 5w30 or 10w30. Quietest oil I have run in my Jeep, as well as a few other members on here. I also returned a UOA with single digit iron wear numbers, it is floating around this forum somewhere in the UOA section. Personally, I felt the Rotella T6 was a bit too thick, especially on start up in the winter. Here is a link to the UOAs with Pennzoil: Jeep 4.0 Pennzoil UOA

 

[thorromig]

For the price -- QSUD 5W30 & Fram Ultra all day. That motor will luv that combo!!!

 

[Dyusik]

HDEO in a 10w30 or 5w40, seen people run SAE30 and SAE40 with same luck as anything else. Valvoline comes to mind as well. I have seen people have better #'s with 10w vs 5w on uoas if that means anything. Hard to give, or take power from that 242, and in reality "anything" is the correct suggestion.

 

[barkingspider]

Any Xw30 brand you like best will do

 

[Kuato]

Originally Posted By: ChrisD46

*Regarding M1 high iron levels : Wasn't that just one year due to a hurricane causing the need for a temp formulation change ?

Nope. Across several years. In several different 4.0s

 

[02s4audi]

Originally Posted By: jeepman3071

Pennzoil conventional 5w30 or 10w30. Quietest oil I have run in my Jeep, as well as a few other members on here. I also returned a UOA with single digit iron wear numbers, it is floating around this forum somewhere in the UOA section. Personally, I felt the Rotella T6 was a bit too thick, especially on start up in the winter. Here is a link to the UOAs with Pennzoil: Jeep 4.0 Pennzoil UOA

Wouldn't rotella be thinner at start up as it's a 5w?

 

[mpersell]

My 4.0 Jeeps in the past loved a stout 10w-30. I used Amsoil or Schaeffer. They're a noisy engine but the 10-30 kept them quieter than the 0w-30 or 5w-30.

 

[dieselfarmboy]

Id be more worried about frame rust then what oil to put in it.

 

[Building3]

For my 2003 4.0L the dealer used conventional Pennzoil 10w-30. Once out of the warranty period I have been changing it myself with Pennzoil Ultra Platinum 10w-30. Oil analysis shows no issues. Ambient emperature ranges from -10 to 95 degrees in Michigan.

 

[02s4audi]

Surprisingly this 4.0 is very quiet