5W-20 or 5W-30 ???

[ZooL]

Hello from Athens, Greece

About a month ago I picked up a used '08 Jeep Grand Cherokee WK 3.7L with 68k miles on the clock.

As soon as I got my hands on it I changed all fluids on the truck. And as both the owner's manual and the refill cap suggested, I used 5W-20 oil (Amsoil synthetic).

A few days later I noticed a ticking sound from the engine. Even the wife noticed it, said the Jeep sounded like a diesel...

At that time I also came across some service receipts that the previous owner had kept among the Jeep's documents, where I found that the dealer (and sole Jeep importer here in Greece) who's been servicing the truck since day one had been using 5w30, from the very first service...

I'm not really sure if the ticking sound I hear is related to the oil change, but I'm leaning towards flushing the *correct* 5W-20 oil and going back to the *wrong* 5w30 that's been used in the engine all it's life...

What would you do?

X.

 

[ChiTDI]

With 68k on the odo, I'd run the amsoil for a shorter than normal interval, and then change again using the amsoil 5w20.
Maybe have that short interval drain analyzed and go from there.

 

[ChiTDI]

Btw - was that 5w30 synthetic or mineral?
Two issues if it was mineral.

 

[ChiTDI]

And last but most, WELCOME !

 

[CATERHAM]

First welcome to BITOG!

The Amsoil 5W-20 you're using is actually at the heavy end of the 20 grade range so not that much lighter than a A1/B1 or A5/B5 5w30 particularly a mineral oil in service.

The ticking you're hearing is likely from the valvetrain and may not be viscosity related. There are other aspects of an oil that can have an effect on engine noise such as entrainment tendencies.
It may even be just the fuel injectors but you need to first identify the exact source of the noise before doing anything.
Is the noise present at all times including when the engine is cold and during warm-up?

 

[ZooL]

Thank you ChiTDI

The word around here is that the quality of the oil they use at the dealer's is below par...

What if it was mineral then?

 

[ZooL]

And thank you CATERHAM

My mechanic also suggested that the ticking sound could be from the fuel injectors; I will have them cleaned someday next week.

 

[widman]

Find a bottle of Techron before letting anyone play with injectors. I presume your 68K is km, which is not much. I ran 5W-20 in my 2009 for the 43,000 km I had it before getting a 2012, and never heard a sound.

Lifters could also have varnish in them, or it could have sludge from short trips or poor oil. AutoRx comes to mind, but I don;t know if you can find that.

 

[tig1]

Originally Posted By: widman
Find a bottle of Techron before letting anyone play with injectors. I presume your 68K is km, which is not much. I ran 5W-20 in my 2009 for the 43,000 km I had it before getting a 2012, and never heard a sound.

Lifters could also have varnish in them, or it could have sludge from short trips or poor oil. AutoRx comes to mind, but I don;t know if you can find that.


Cleaning the injectors will have nothing to do with the sound injectors make. All injectors make a clicking sound caused by the injector opening.

 

[Kuato]

Odd that the cap says 5w20. I had the 3.7 in a 2004 vehicle and it was specified to use 5w30. I don't believe there were any mechanical changes between 04 and 07, so I would be inclined to use 5w30.

Is it possible someone else got rid of it because of the ticking?

 

[ZooL]

Thank you widman, tig1

Originally Posted By: tig1
(...) All injectors make a clicking sound caused by the injector opening.

We've had another Jeep in the family (Liberty KJ 3.7L) with the exact same engine; it always purred like a kitten, never noticed a ticking sound or any other alarming sound of any sort. (This one got Amsoil treatment since new).

Is there any risk involved cleaning the injectors? Mechanic said it would might also help bring down fuel consumption (a bit).

Is this the Techron you mentioned? http://www.techron.com/techron-concentrate-plus/Default.aspx

Along with the AutoRx you mentioned, If I can't find them here I could try and source them from the US or Germany.

Btw, the engine has 68k miles, or 111.000 km.

Thanks again for all your help.

X.

 

[ZooL]

Originally Posted By: Kuato
Odd that the cap says 5w20. I had the 3.7 in a 2004 vehicle and it was specified to use 5w30. I don't believe there were any mechanical changes between 04 and 07, so I would be inclined to use 5w30.

Was it a Grand Cherokee WK the one you had?

I know for sure that the 3.7L engine the KJ Liberty got (2002-2007) was spec'd for 5w30, even though it was the same engine with the WK's. (The only documented difference I've found is that the engine version in the Liberty had a compression ratio of 9.6:1 as opposed to 9.7:1 of the Grand Cherokee).



Originally Posted By: Kuato
(...) Is it possible someone else got rid of it because of the ticking?

Let's say that I try not to think about that...

 

[Kuato]

Originally Posted By: ZooL
Originally Posted By: Kuato
Odd that the cap says 5w20. I had the 3.7 in a 2004 vehicle and it was specified to use 5w30. I don't believe there were any mechanical changes between 04 and 07, so I would be inclined to use 5w30.

Was it a Grand Cherokee WK the one you had?

I know for sure that the 3.7L engine the KJ Liberty got (2002-2007) was spec'd for 5w30, even though it was the same engine with the WK's. (The only documented difference I've found is that the engine version in the Liberty had a compression ratio of 9.6:1 as opposed to 9.7:1 of the Grand Cherokee).


Agreed; they changed the compression ratio in 2005, but I don't see any other mechanical changes.

http://www.allpar.com/mopar/37.html

To answer your question I had the 3.7 in a rental Liberty for awhile in 2003, and in a Dodge truck model year 2004. Both were 5w30.

 

[Sam2000]

I would use Techron as it is a proven and often manufacturer recommended maintenance item.

I wouldn't use an oil additive.

I would run the Amsoil for a while and see if the noise settles down. It is unlikely to be harming anything.

If the noise remains, I would consider changing oil / grade but it would be a waste to remove the Amsoil earlier than its useful life.

 

[SLATRON]

The amsoil site specs 5w20 for the year engine. And since manual &cap says also it should be fine. Ive have car that recommends 20 grade but 30 okay to use. I find the 20 makes engine more noisy than 30, which is kinda of. Irritating but don't think its hurting anything.
I just use thin 20s in winter and some 30s in heat of summer, mainly because I've found lots of 30 grades with huge sales.
However, as stated above maybe that's a reason previous owner got rid of the Jeep. But I've had two 4.0 and one 3.7 and thought very tough little engines.

 

[Merkava_4]

1. Drain the oil
2. Refill with conventional non-synthetic 5w30
3. Enjoy your new quiet engine

 

[Eddie]

Run the oil you have in it now for 3K miles and then the 1,2,3 above.

 

[123Saab]

Our 08 Liberty with the 3.7l calls for 5w-20 and is a nice quiet smooth running engine.

Valvoline Nextgen and Bosh Premium Filter for the last 2 years.

 

[earlyre]

Originally Posted By: Kuato
Originally Posted By: ZooL
Originally Posted By: Kuato
Odd that the cap says 5w20. I had the 3.7 in a 2004 vehicle and it was specified to use 5w30. I don't believe there were any mechanical changes between 04 and 07, so I would be inclined to use 5w30.

Was it a Grand Cherokee WK the one you had?

I know for sure that the 3.7L engine the KJ Liberty got (2002-2007) was spec'd for 5w30, even though it was the same engine with the WK's. (The only documented difference I've found is that the engine version in the Liberty had a compression ratio of 9.6:1 as opposed to 9.7:1 of the Grand Cherokee).


Agreed; they changed the compression ratio in 2005, but I don't see any other mechanical changes.

http://www.allpar.com/mopar/37.html

To answer your question I had the 3.7 in a rental Liberty for awhile in 2003, and in a Dodge truck model year 2004. Both were 5w30.


not Entirely Related, But My Former Neon, was a 2005. Final Model year. manual and Cap said 5w20. Every MY Prior to 2005, called for either 10w30, or 5w30.
I just assumed it was a CAFE switch.

 

[901Memphis]

Run the Amsoil 5w20 5k then switch to Amsoil 5w30 or Mobil 1 0W40 European Formula if it's not too expensive.

The noise doesn't necessarily mean wear but it will drive you crazy which is reason enough to switch. My engine is quieter on mineral oil than synthetics but I still run synthetic most of the time.