5W-30 vs 5W-20

[RageOfFury]

There is this debate going on at BITOG forums. People are saying that there is NO reason whatsoever to use 5W-30 is Chrysler's Powertech engines(3.7, 4.7). That all of us with jeeps and trucks with those engines should switch to 5W-20 even if the recommended oil on the oil fill cap is 5W-30.

Thoughts?

 

[Marlon_JB2]

Better fuel economy with 5W20.

 

[loves_off_roading]

You could probably get away with using 5W-20 or 10W-30 but I would stick with what the manufacture recommends.

 

[tjkj2002]

Better fuel economy with 5W20.

At the cost of reduced engine life.

I like oil pressure.

 

[mag03kj]

use what you want to. but dont use a fram filter lol(rotflmao)

 

[eyehatetofu]

Oh no, not the great oil viscosity debate again...

(popcorn)

 

[Marlon_JB2]

I *personally* run 5W30 in my 3.7L *despite* Chrysler's recommendation for 5W20.

 

[HoosierJeeper]

I'm running 5W30 in the KJ.... 5W30 in the Durango (no MDS), even though they recommend 5W20.

 

[AlexKJ]

I use 10W30 Chevron Supreme Synthetic (b/c there is nothing more to choose in 5W30 or 10W30, besides Shell)... Where I live, we never get even close to -18°C (0°F)... so using 5W30 is pointless to me... In the other hand, we are getting temps over 35°C (95°F)... I wonder if it be reasonable switch to a 10W40... but I'm not gonna try it if I'm not 110% sure...

 

[long_tall_texan]

My 07 manual recommends 5W20 for all seasons...

 

[JeepJeepster]

I'm running valvoline 5w-30 right now, but when I do my amsoil syn switch at 3k miles I might switch over to 10w-30 since it gets hotter here so I think it will do my engine better.

Personally I use 5w-30 in the winter and 10w-30 in the summer. Guess you can use 10w-30 year around.

Use 5w-20 in the hemi and it pours out about like water when its hot. Made some nice messes in the driveway the first time I changed that oil!

 

[diyman]

Hey guys!

Another j**k (that's ME!) joining the endless viscosity discussion...

Where I live, everyone thinks the thicker the better, but I recall
reading an article sowhere ( more than 160 kBytes...) about the
issue. The guy explains why thinner is usually better. He maintains
that what protects engines from wear is flow, not pressure, and
that the W number, the lower the better, as it prevents start-up
wear. I feel like subscribing to his point of view, but I'd NEVER
use 5W-20 on my beloved KJ anyway. There must be a limit to..

( Regrettably they don't sell 5W-30 here or I'd be using it )

Unwisely ( I assume ),some oil makers sell 25W/65 engine oils,
intended for high mileage engines. In my (humble) opininion
that's the way to end destroying the engine.
Better have it overhauled...!!!
You wouldn't put grease in Your engine, or do You?

Anyone thinking I'm in favour of engine wear, I'm no Pro and don't
like anyone's car breaking down!!! Least of all MY Liberty....!
( No flaming here, just kidding guys, don't get upset.. )

 

[Dave]

There is this debate going on at BITOG forums. People are saying that there is NO reason whatsoever to use 5W-30 is Chrysler's Powertech engines(3.7, 4.7). That all of us with jeeps and trucks with those engines should switch to 5W-20 even if the recommended oil on the oil fill cap is 5W-30.

Thoughts?

My 05 owners manual says 5w-30 preferred and so I run that weight and feel comfortable with it. If I lived in Florida where it is hot all the time I would be using 10w-30. Where you live could make a difference in your oil weight selection. The manual says you can run this weight also in warmer climate.

As to the 5w-20 I think that is a fuel economy thing. I don't think the factory/engineers did anything special to the engine when they started recommending the 5w-20 as far as I know. I wonder what your dealer would say if you called them and asked them if you switched oil weights if your engine warrenty is still good? That might be interesting.

The most important thing to me is proper engine lubrication and not the .0005 % more mpg I might get with the lighter weight oil.

Just my opinion. Yours may vary.

Dave

 

[RageOfFury]

IMO I say screw CAFE. That's the only reason(I believe that's the only reason) why Chrysler started to recommend 5W-20 is to gain a few MPG and get CAFE off it's back. However, as TJKJ said earlier, this MPG gain comes at the expense of engine protection.

So yeah, stick with xW-30 in these engines.

 

[04Liberty]

This is a huge debate on the Dodge Forum about the 4.7's. A guy took his 4.7 Ram to a dealership for oil change and they put 5W-20 in it. It says 5W-30 on his oil cap, but the service manager claimed Chrysler sent out a bulletin stating to use 5W-20 on all 3.7's, 4.7's and 5.7's that came in for oil changes. Supposedly the 4.7's have a long history of sludge related failures. The 06 and newer 5.7 needs it for the MDS solenoids to work properly. I told the guy to ask for a copy of the bulletin, but didn't hear anything about it. With these newer engines and modern oil technology, old school thought about the heavier weight the better doesn't always apply anymore. I say if you go with what is in the service manual for the vehicle (and I have alot of these besides the two I actually need) or on your oil cap you can't go wrong.

 

[tjkj2002]

This is a huge debate on the Dodge Forum about the 4.7's. A guy took his 4.7 Ram to a dealership for oil change and they put 5W-20 in it. It says 5W-30 on his oil cap, but the service manager claimed Chrysler sent out a bulletin stating to use 5W-20 on all 3.7's, 4.7's and 5.7's that came in for oil changes. Supposedly the 4.7's have a long history of sludge related failures. The 06 and newer 5.7 needs it for the MDS solenoids to work properly. I told the guy to ask for a copy of the bulletin, but didn't hear anything about it. With these newer engines and modern oil technology, old school thought about the heavier weight the better doesn't always apply anymore. I say if you go with what is in the service manual for the vehicle (and I have alot of these besides the two I actually need) or on your oil cap you can't go wrong.

There is no bulletin for switching all engines to 5w-20.They do have bulletins for ATF+4 and coolant but none for oil weights.

As far as the HEMI's needing 5w-20 for the MDS to work is a crock of s$%t,the engine has no idea what weight of oil is in it and the MDS will work with 5w-30 and even 10w-30.It's a scam just like the oil companies used to pull by saying once you switch to synthetic you could not switch back to dino oil.The whole 5w-20 thing is to comply with CAFE and that is all.

 

[ridenby]

Amen

 

[Dave08]

How does everyone feel about Amsoil 0W-30. I don't see why there is an arguement over 5W-30 and 10W-30. Shouldn't one simply flow better in the winter when the coil is cold

 

[04Liberty]

There is no bulletin for switching all engines to 5w-20.They do have bulletins for ATF+4 and coolant but none for oil weights.

As far as the HEMI's needing 5w-20 for the MDS to work is a crock of s$%t,the engine has no idea what weight of oil is in it and the MDS will work with 5w-30 and even 10w-30.It's a scam just like the oil companies used to pull by saying once you switch to synthetic you could not switch back to dino oil.The whole 5w-20 thing is to comply with CAFE and that is all.

That may be so, but not using that 5W-20 in your MDS engine (or if any other engine actually calls for it) will screw your pooch for warranty claims.

 

[Marlon_JB2]

There is no bulletin for switching all engines to 5w-20.They do have bulletins for ATF+4 and coolant but none for oil weights.

As far as the HEMI's needing 5w-20 for the MDS to work is a crock of s$%t,the engine has no idea what weight of oil is in it and the MDS will work with 5w-30 and even 10w-30.It's a scam just like the oil companies used to pull by saying once you switch to synthetic you could not switch back to dino oil.The whole 5w-20 thing is to comply with CAFE and that is all.

... ahem....

Need to step in here for a minute.

Sorry Troy, but MDS really won't work correctly without 5W20.

How do I know this?

My aunt has a '06 300C.

Went to go get an oil change, and immediately noticed a highway mileage drop. I asked her what kind of oil was used, she said the paperwork said 10W30.

About 2 oil changes later, with 5W20...

All was back to normal.