I've spun bearings on every 3.7 I've owned..

[3.7Mech]

Background: I ran 30W MaxLife blend with Napa Platinum filter at 4k intervals. One was 2003 one was 2006 both 3.7 4x4.

Both eventually spun or broke a bearing just commuting on flat grade pavement. The second one a slight knock but would stall at lights and barely start with oil light showing; oil was proper level battery was new and recharging

My question is: was there ever a known defect with the oil pumps? Both of these died the same way with ideal maintenance, but only once they got over 100k.. It seems the oil pump does something to circulation and heat nukes bearings.. Maybe oil pump doesn't handle a high rev on a random takeoff after 100k somewhere?

 

[LibertyTC]

30 weight oil ?
The KJ gasoline 3.7 OEM specification is 5W-30

 

[burntkat]

Two problems...

You're running 30 weight oil.... Why? Spec is 5w30..

And Valvoline Maxlife? If you've had oil issues, why on earth are you running the same oil, still?

 

[3.7Mech]

Since when do people use the cold-viscosity rating to describe weight? It was 5-30W, because it says it on the cap and in the manual..

Why would I use a top-rated brand high mileage oil and filter on a 130k and 150k engine? Gee.. let me think..

If you want to go for it was Valvoline oil with high-mile detergents then more power to you.. lol. I'll stick to some kind of oil-pump defect myself, because mass-market tested oils don't wipe out engines without defects..

BTW I don't rule out the PS and IAC *defect* mentioned on these forums for the last one(2006); clinking after a hard start then oil light. The first didn't have similar symptoms; was just going down highway 55MPH in 60F.

 

[derekj]

Hard life before you owned them maybe?

 

[KJowner]

Shot injectors dropped fuel into the sump when the engine stops??
Racing it from cold?
Previous lack of oil changes?
Bad luck?
Without oil samples and an engine autopsy it's not an easy answer.

 

[belvedere]

Maxlife is a good oil. Still a little confused on which viscosity you used. You said "30W", but then implied that you used 5W30.

 

[Him73067]

I would bet it is your 4K interval. But that is just my guess.

 

[JeepKJ_Guy]

Since when do people use the cold-viscosity rating to describe weight? It was 5-30W, because it says it on the cap and in the manual..

Why would I use a top-rated brand high mileage oil and filter on a 130k and 150k engine? Gee.. let me think..

If you want to go for it was Valvoline oil with high-mile detergents then more power to you.. lol. I'll stick to some kind of oil-pump defect myself, because mass-market tested oils don't wipe out engines without defects..

BTW I don't rule out the PS and IAC *defect* mentioned on these forums for the last one(2006); clinking after a hard start then oil light. The first didn't have similar symptoms; was just going down highway 55MPH in 60F.

You have said - "Ran 30W MaxLife blend - Since when do people use the cold-viscosity rating to describe weight?" - Answer - since forever!, - I learned that in the 60's by my Dad how important it was - if it's 30W then its SAE 30W lawnmower oil - it stays 30W all the time, thru any temperature, - it would be like tar in below zero weather.

I have run Mobile 1 SAE 5W-30 FULL Synthetic Extended Wear and filter since forever, changed at 4k - Zero problems.

You say - "Why would I use a top-rated brand high mileage oil and filter on a 130k and 150k engine? Gee.. let me think.."

Answer - Because at that high of mileage you need all the protection you can get!!

Watch the testing results on Youtube and read the various forums about testing oil of Mobil 1 - it's the best bang for the buck, I run it in my 350 Z-28 too - Zero problems.

You can buy 5qt easily at Walmart or Amazon for about $28 dollars - NEVER go cheap on oil as the ole man taught me, and NEVER had any engine problems.

 

[CheddarGau]

So the cold viscosity is super important. 5W is the viscosity when cold. 30 is the viscosity at operating Temps. Essentially the lower number determines how well the oil will flow/lube on cold start or winter (W stands for winter) and the 30 is its flow/lubrication when engine is hot. Typically unless an engine has worn bearings, cams, cranks, etc, we Typically don't suggest going with a thicker cold viscosity(there are always exceptions, such as Toyota 2.7L engines). I'm assuming you were referring to 5W30 oil. For example If you were using 30W30 oil a 3.7L would have very poor flow on cold starts and extremely poor flow on winter cold starts, which would greatly contribute to premature engine wear. This isn't judging anyone, but helping people make the best future decisions. Ultimately each vehicle is different. My nieces 05 liberty can't use synthetic or 5w20, it burns it too much too quickly. She must using 5w30 concentional. That seems to be the sweet spot.

Where that W is placed 5-30W vs 5W30 refers to two very different oils. Again not about bashing, but can really help with any misunderstandings.