5w30 in jk 3.8?

Jeeper125

Jeeper125

New member
What oil is everyone running in their 3.8 I've heard that 5w30 was better to run over the recommended 5w20.
 
madstiles

madstiles

New member
Mobil 1 full synthetic high mileage 5-30 I'm at 80,000 I put the same in my Avalanche it makes it cheaper buying 1 weight
 
Stotch

Stotch

Caught the Bug
I was burning about a quart in between oil changes with 5w20. Made the switch to high mileage 5w30 and the consumption seems to be about half that. I'm at 98k miles.
 
loonies

loonies

Member
5w30 here...my 3.8 was burning 1.5 quarts every 1000 miles with the 5w20. It barely burns any with the 5w30. 44K miles on my 2010
 
D

DKjeep

New member
Been using mobil 1 full synthetic 5w20 since I got the jeep when it was just shy of 5k miles. I have been on a 7500 to 9000 mile oil change interval as well. It uses about 1qt per 3k miles and has done that since day 1. It's at 111k miles now and I recently pulled the pan and a valve cover to facilitate some other work and I was beyond belief with how clean and brand new everything looked. Not one trace of sludge or even looking dirty. I did a compression test at 105k miles while I was replacing plugs. It was superb and all cylinders were within 3psi of each other.
 
robx251

robx251

Caught the Bug
The 3.8 liter V6 was originally designed to have 5W30 in it when it was put in the Grand Caravan originally. I believe that Mopar due the cafe standards has had to knock it down to 5 w20 to help try and get the fuel economy up it does lead to higher oil consumption running a lighter viscosity due to burn off. I've run anywhere from 15w40 to 0w20 in my 2010 when I had it. Obviously the heavier the weight oil the quieter the engine runs with less top end valve noise. I would encourage running 5w30
 
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notnalc68

notnalc68

That dude from Mississippi
robx251 said:
The 3.8 liter V6 was originally designed to have 5W30 in it when it was put in the Grand Caravan originally. I believe that Mopar due the cafe standards has had to knock it down to 5 w20 to help try and get the fuel economy up it does lead to higher oil consumption running a lighter viscosity due to burn off. I've run anywhere from 15w40 to 0w20 in my 2010 when I had it. Obviously the heavier the weight oil the quieter the engine runs with less top end valve noise. I would encourage running 5w30
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The 3.6 originally used 5w30, and changed in 2014, I believe was the year, to 5w20. Probably for the same reason.
 
DINKELROC

DINKELROC

New member
This is good information, I'm at 150k and burning 1.5 qt between changes, gonna try this and see what happens.
 
JeepDrum

JeepDrum

New member
I've been running pennzoil high mileage 5w30 for the past 2 oil changes. My engine seems to be a little quieter but I'm still losing about a quart every 1000 mi. It seems like I have a small leak somewhere so that's why I put in the high mileage. I was hoping that would help the seals a little. I've even heard of people running 5w40.
 
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