What are symptoms of worn rocker arms?

fatweasel · **Posted:** Thu Mar 14, 2013 4:48 pm

Sounds like there have been more than a few cases of worn rocker arms lately. What symptoms would the engine exhibit if the rockers were getting worn?

Drewd · **Joined:** Mon Feb 06, 2006 12:24 pm **Posts:** 902

0W-40 usage is usually culprit.

If you search this forum you can find how to read the idle mass air flow and see if it is around the ideal values posted by GDE. Worn rockers mean less airflow.

Shot rockers/lifters are now suspected to be cause of "skipped" timing belt problems.

LS12FAST4U · **Posted:** Thu Mar 14, 2013 10:48 pm

That's why as a parts salesman I always recommend staying with manufacturer recommendations 5w40 full synthetic is what should be in there.

Srytrucker · **Posted:** Fri Mar 15, 2013 12:22 am

LS12FAST4U wrote:

That's why as a parts salesman I always recommend staying with manufacturer recommendations 5w40 full synthetic is what should be in there.

Are you serious ? the mfg are the ones who were propagating 0w40 and causing all these troubles.....

Glend · **Posted:** Fri Mar 15, 2013 5:10 am

I think he means VM, who made the engine, not Chrysler Jeep who wanted tio improve fleet fuel economy through promoting thinner oil use.

DOC4444 · **Posted:** Fri Mar 15, 2013 7:54 am

I believe that soot in the oil will prove to be the main culprit. We have been running for 80 of the 110K miles on our rig with EGR disabled and mostly 0W-40 oil (5-40 in summer).

The MAF idle numbers look good (19.5). So, we will have to see.

DOC

fatweasel · **Posted:** Fri Mar 15, 2013 12:27 pm

Any iPhone OBDII apps that work on the Liberty CRD to read mass air flow at idle?

kjjet · **Posted:** Fri Mar 15, 2013 1:48 pm

I had worn rockers and the Jeep ran great untill I started it after getting some Beer. (it was a Friday like today) O ya then then it jumped time.

After all the work and parts, it is running even better. You never know when its your time.

As far as what cause's it. EGR.....the sooner it is gone the better for your engine. 0w-40 is what the MFG wants you to run. Time will tell if it has any bearing on rockers or not. GDE has reported one but it had a operating EGR all its life.

With no EGR and new rockers we will see what the rockers look like at the next t-belt. I will remove the intake for inspection. Sticking with Mobil 0w-40.

Big Montana · **Posted:** Fri Mar 15, 2013 5:40 pm

LS12FAST4U wrote:

That's why as a parts salesman I always recommend staying with manufacturer recommendations 5w40 full synthetic is what should be in there.

In this case, my Jeep has called for 0W 40 since new. Your manual asks for it.

Glend · **Posted:** Fri Mar 15, 2013 6:27 pm

Export model spec is 5w-40 or 10w-40 and no reported rocker problems.

LS12FAST4U · **Posted:** Fri Mar 15, 2013 8:45 pm

Who do you trust more the company that bought the engine or the company that MAKES the engine? To each his own though.

TJ2 · **Posted:** Fri Mar 15, 2013 11:38 pm

God must have loved stupid people. . . he made a lot of us. 2fast obviously lives in the UK. He is not the first to come to the board and make absurd statements. (he's rude besides). He reminds me of the Brit who leased (not drove the London Taxi). He assumed he knew all about Jeep specs and the 2.8 (I doubt if he's seen either).

Glend: the 5/40 10/40 recommendation for the VM is very hard to find using the search engines in the US. Actually, I never have. VM is not a member of ACEA (since they're not an automobile manufacturer). The Russian site even recommends 0/40.

Things are not as clear cut in the US, as far as available information as some of you obviously think.

FWIW, I'm NOW on a road trip and have just finished a week in Death Valley Nat'l. Park. I was grinding around at 95 F and felt great having 10/40 API CI-4 Plus (made from Group IV base stock) in the crankcase.

I'll be switching to PAO base 15/40 when it warms up.

Why do so few people see that the EGR values in the US (far higher than the rest of the world) are a major contributor. Well, I guess a few do.

Of course, YMWV

Glend · **Posted:** Sat Mar 16, 2013 5:13 am

Well for me the 10W40 recommendation is very easy to find, it's sitting right in front of me on page 119 of my Jeep Cherokee Operating Information booklet (aka Owners Manual) which was published by Chrysler Corporation in early 2007, printed in the USA and delivered with my vehicle. (Background: The KJ was produced until the end of April 2007 for the Export market and then the factory shutdown for KK retooling. These KJs were sold in the Export market as a 2007 model, which has a different model change over timeframe to the US market).

On page 119 of my manual it says:

"Engine Oil Selection - Diesel Engines

To assure of properly formulated engine oils, it is recommended that SAE grade 10W-40 engine oils that meet DaimlerChrysler MS-6395 be used in accordance with ACEA B3,B4 specification.....Oils of SAE 5W-40 grade are preferred when the minimum temperatures consistently fall below -15C (5F)."

[url]It makes no mention of 0W-40 grade oils.[/url]

Further, I have emailed VM Motori asking them what oil specification was recommended by their engineers when the R 428 was developed.

Also, the 2.5 L version of this engine is used the LTI produced London Taxi, the TX4 model. The LTI TX4 owners handbook pdf file, which can be downloaded from here
http://www.coventry.gov.uk/download/dow ... ndbook_tx4

on page 57, specifies 10W40 (in the main) but also says that 5W40 or even 0W40 can be used where extreme cold start ability or improved fuel economy is required. There are LTI TX4 forums and I can't find any concerns about rockers mentioned on there.

Joe Romas · **Posted:** Sat Mar 16, 2013 8:48 am

Glend
What you say is all well and good for everyone but those of us in the North American market :SOMBRERO:

As it shows in my profile I live in the US and on page 320 of the 2006 first edition manual that came with my 2006 new it states
USE SAE 0w-40 oil meeting API SL and CF or better and DC material Standard MS-10725. If you can not find 0W-40, then SAE 5W-40 Synthetic Engine Oil is acceptable".

Now some of us who may have had other diesel powered vehicles realized there was a problem right off with the CF ZERO rated oil and used the "if you can't" find statement and used use CJ-4+ rated Rotella or Mobil 1 Turbo Diesel Truck 5W-40 oil that is available to us instead.
As TJ2 says the oil that is widely available to you is next to impossible if at all to find in the US.
Also non North American market CRD versions have far less EGR in stock configuration.
Put another way what DC recommended for North American buyers is like a mixture of sand (soot from the EGR) and water (zero weight oil) to lubricate our CRD's :dead:

DOC4444 · **Posted:** Sat Mar 16, 2013 1:08 pm

FAT,

The "Dynolicious" app was suggested on a forum. I do not know about ability to read MAF values, though.

DOC

Srytrucker · **Posted:** Sat Mar 16, 2013 1:36 pm

It has been a majority consensus that Soot and thinner oil 0w40 is causing all the issues here and if you read deeper into it when one tries to stick with 0W40 his only option is Mobil1 it has to be the missing additive pack in that oil package and lack of options and on the other hand people who opted for second option 5W40 oils , had options in turn like Shell rotella T6 (though not a full syn) ,Mobil 1TDT or Amsoil all good proven options based on UOA.
So take your pick.

DOC4444 · **Posted:** Sat Mar 16, 2013 1:44 pm

Forgot to mention we have been running ZDDP (4 oz, adds missing zinc) with each 5K oil change (00W-40, winter/ 5W-40 summer).

DOC

tcoilburner · **Posted:** Sat Mar 16, 2013 2:05 pm

Before we all blame the 0W40 CF rated oil, I have had no problems with it for the first 90,000 miles, can any one tell us the additive difference between a CF and CJ4 rated oil? Just because it is newer does not mean it is better, remember the goverment is coming up with this regulation. Does one or the other rating have more antiwear additive than the other (Known for sure). I has been my understanding that the goverment has been removing stuff for the oil for aleast the last 7 or 8 years?

The only think I know for sure is last late summer the CF rating on the Mobil1 0W40 was removed. So I switched the last oil change I did in December to Delvac1 5W40. The only problem I have seen with it is, it cost me about 2 mpg driving back and forth to work durring the week. I only am up to operating temp for a mile or two max. On long trips it only has change rough a 1 mpg. I would like to switch back to a good 0W40 for the mileage and the fact the oil will get through the engine on cold starts quicker. :2cents:

mark2m · **Posted:** Sat Mar 16, 2013 3:09 pm

I inspected my rocker arms when I did my timing belt job and changed my head gasket. I have no play on the roller bearing and the usually wear marks on the rocker tip wear it contacts the valve stem. They were in great shape, I change my oil around the 12k miles mark and use Rotella T6 for over 45k miles at least. GDE Hot Tune and EHM also.

Here they are installed.

Srytrucker · **Posted:** Sat Mar 16, 2013 3:34 pm

tcoilburner wrote:

I would like to switch back to a good 0W40 for the mileage and the fact the oil will get through the engine on cold starts quicker. :2cents:

That is all good and dandy please let me know if you find any other 0W40 oil besides Mobil1. My point is there are no options.Thanks.

What are symptoms of worn rocker arms?

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