manufacture's oil recommandations

[ShafferNY]

Our '06 is due for it's first oil change since we bought it used. The oil filler cap says 5w-30, and the owner's manual say to use 5w-30 for all climates.

My '03 on the other hand has NO recommendations on the oil filler cap and the owners manual has a chart as to what weight oil to use.

I've always used 5w-30 during the winter, and 10w-30 in the summer in my vehicles.

Did something change about the 3.7L from '03 to '06, or just the recommendations?

 

[HoosierJeeper]

I'm pretty sure nothing changed on the 3.7l. I think they just changed the
recommendations toward better fuel economy. That's what I'm thinking....

 

[JeepJeepster]

I've always used 5w-30 during the winter, and 10w-30 in the summer in my vehicles.

Thats what I do in my 3.7..

 

[HoosierJeeper]

Thats what I do in my 3.7..

Where I am, we have 2 seasons: hot and hotter. No need to use different grades of oil.I wish I could, that would mean I live near snow!!!

 

[Powerslave]

I do the same, 5W winter, 10W Summer. Sometimes I use 10w40, did in my Avenger, and it had 145k miles on it when I traded it in, all original powertrain.

 

[Dave]

I run 5w30 weight in mine all year. You can run 10w30 in the summer per the owners manual though. I have not had any problems with mine running the 5w30 (syn) since I bought it new. I know for sure what's in mine because I do all the oil changes myself.

I think you could run either, but the 5w30 is preferred for real cold weather according to my 05 manual anyway. I don't think the motor changed as far as I know. You should be ok with either weight oil.

Strange that your oil cap does not say the weight on it. Maybe the OEM one was replaced. All vehicles I have noticed (mostly GM and Jeep though) have the oil weight on the cap.

Dave

 

[sleeve]

The only change in the engine was in 2007 when the 3.7L was "converted" to run off of 5w20. Any model year before that can survive on 5w30 year round.

Even the guys living 1/4 mile from the sun [South West Deserts] have only needed the recommend 5W/10W30 for the KJ.

 

[ShafferNY]

Thanks for the replies.

I'll probably put 10w-30 in it.

 

[Simpleman]

Engines today are built with much tighter tolerances than engines twenty years ago. That is the main reason 5W-30 is recommended. When cold the heavier weight will take longer to get to the moving parts and can cause premature wear. In hotter climates 10W-30 wont really harm anything.

 

[tjkj2002]

The main difference between 5w-30 and 10w-30 is that the 5w-30 will start to lubricate critical engine parts sooner then 10w-30 will at any ambient temp,both have the exact same "hot" viscosity of 30w oil.Stick with 5w-30 all year round and you should not have any problems,no need for 10w-30.

 

[belvedere]

Stick with 5w-30 all year round and you should not have any problems,no need for 10w-30.

+1

 

[flair1111]

The main difference between 5w-30 and 10w-30 is that the 5w-30 will start to lubricate critical engine parts sooner then 10w-30 will at any ambient temp,both have the exact same "hot" viscosity of 30w oil.Stick with 5w-30 all year round and you should not have any problems,no need for 10w-30.

thats what i thought too. wasnt sure.

 

[JJsKJ]

The main difference between 5w-30 and 10w-30 is that the 5w-30 will start to lubricate critical engine parts sooner then 10w-30 will at any ambient temp,both have the exact same "hot" viscosity of 30w oil.Stick with 5w-30 all year round and you should not have any problems,no need for 10w-30.

Totally agree. Changing oil viscosities at different times of year is a waste of time.

 

[Powerslave]

Well, I will stick with what has worked for me, for 9 years with my former Avenger.

 

[sleeve]

The avenger / sebring engines are different from the 3.7 in the KJ.

The KJ likes a thinner oil. I believe it only uses 5PSI at idle or something like that.

 

[offrovering]

there is more than just viscosity, like higher HTHS rating helping with cam wear, and other wear. a 0w30 may have just as high a rating as a 15w40, which are completely different. check ratings on back of bottles, it isnt just about the XwXX

edit: publised before I was done.

everyone drives different and has different needs. the engine has a basic rating so a 5w30 will work for most, but some people may find a better oil for their uses. I don't think these engines are known for much sludging?? so I wouldnt think anything special is needed.

 

[CHUD]

The only change in the engine was in 2007 when the 3.7L was "converted" to run off of 5w20. Any model year before that can survive on 5w30 year round.

I just started running 5w20 in my 02 with my last oil change. I like the Jeep's performance better now than with the 5w30 I previously ran. I'm going to keep using it.