2009 Wrangler 3.8, High Mileage, thicker viscosity, etc?

[John9721]

Good afternoon everyone; My dad today purchased a stock, close to immaculate 2009 Wrangler Sahara today. Manual transmission, no big screen, perfect for his weekend adventures and 2 mile drive to work.

It has 124,000 miles and has been well maintained. It actually came from a customer of my detail and tint shop so I’ve known the vehicle for a long time.

From what I’ve gathered, the 3.8 is a fairly reliable motor, outside of some oil consumption issues that I’ll monitor. Spec is 5w20 which I plan to maintain unless someone tells me otherwise. Being a Mobil 1 guy, my plan for this was Mobil 1 High Mileage 5w20 on a 5000 mile oil change interval. Good to go? I know this is a pretty basic vehicle but I figured I’d make sure I’m not missing anything. TIA!

 

[userfriendly]

I wouldn’t go thicker than 15W-50.

 

[tcp71]

While I know very little about the 3.8 except the oil filter housing is plastic and breaks. There is a metal replacement.

 

[AZjeff]

The 3.8 is known to be a reliable engine, just down around 100 hp on the 3.6. Don't be afraid of a 5W-30 High Mileage oil it's not picky.

 

[Chris142]

No oil will fix the rings that were put on upside down

 

[97K15004WD]

Here's my data on the 3.8L - great engine!

... https://bobistheoilguy.com/forums/t...-miles-with-super-tech-5w30-5600-miles.406063 ...

 

[97K15004WD]

While I know very little about the 3.8 except the oil filter housing is plastic and breaks. There is a metal replacement.

No, the 3.8 has no oil filter housing made of plastic.

 

[HemiBenny]

I used 5W30 (Mobil 1 and Pennzoil) in the 2007 that I owned. (2-door/Rescue Green/6-speed)
I bought it new and didn’t have a single problem with it up until I sold it in 2011 to get my truck. Those old 3.8l engines are very reliable and easy to work on if needed.
I got lucky with the consumption issue, mine didn’t have a drinking problem. A lot of 2007s were affected with the ring situation.

 

[AZjeff]

No, the 3.8 has no oil filter housing made of plastic.

Correct, it's the 3.6 Pentastar that replaced the 3.8 in 2012 that has the plastic housing.

 

[KEVINK0000]

Great engine. Rings can get gunked up in addition to being installed wrong. I use RP 5w30 in mine, even though oil consumption is near zero at 280k. 20w is a mistake in these in my opinion.

 

[cb4017]

I had an 08 Wrangler Unlimited with the 3.8L engine. I ran 5w-30 synthetic in it almost since new. It went 10 years and over 100K miles. Always had great UOAs.

If I ever get another 3.8L it will also get 5w-30.