Why do 6.4 rocker arms wear out and 6.0s dont?

Bustedknuckles · Aug 24, 2016

Just fuel in the oil from regens?

Black AOD · Aug 24, 2016

Because 6.4's suck.

Bustedknuckles · Aug 24, 2016

Black AOD said:
Because 6.4's suck.

Rofl. This is the 2nd 6.4 in a week that needed rocker arms and has insane blowby at just under 150k. We put used 6.0 rockers on all of them and haven't had a issue.

Black AOD · Aug 24, 2016

I don't have a legitimate/logical answer for you. I know 6.4 rocker arms have always worn out severely, even tuned and dlete trucks still wear badly. It's too bad no one ever made a good adjustable billet set, that would probably resolve the issue. The guess about fuel in oil from regens isn't a bad thought. It could be that. Maybe 6.4 rocker arms are made from a cheaper grade metal? I honestly don't know

AirFishAutomotive · Aug 24, 2016

Black AOD said:
I don't have a legitimate/logical answer for you. I know 6.4 rocker arms have always worn out severely, even tuned and dlete trucks still wear badly. It's too bad no one ever made a good adjustable billet set, that would probably resolve the issue. The guess about fuel in oil from regens isn't a bad thought. It could be that. Maybe 6.4 rocker arms are made from a cheaper grade metal? I honestly don't know

a company that we deal with is doing some testing for a hd/billet rocker arm, not sure on progress ill call them before weeks out and see if they have gotten anywhere

sootie · Aug 24, 2016

poor lubrication in the rocker boxes of six fours. There is more oil getting splashed around under the rockers covers of a huei engine vs common rail.

6.4 Stroker · Aug 24, 2016

I did see Ford upgraded the rockers for 6.4s.
Don't have a pic on hand, but it looks like they updated/changed materials on the rocker button.

dboat · Aug 24, 2016

I had mine checked when the oil cooler was replaced and was told they were fine. This is at 165K miles

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78f100 · Aug 24, 2016

sootie said:
poor lubrication in the rocker boxes of six fours. There is more oil getting splashed around under the rockers covers of a huei engine vs common rail.

Exactly, 6.0 injector splash alone oils the rocker more than a 6.4 ever sees.
When running a 6.4 with the valve cover off the only oil that gets to the rocker arm tip is through the small hole above the push rod. It runs down the top of the rocker arm and kinda helps lube the tip, that's a tiny amount of oil. I'm not sure how it looks at wot, but at idle it's not good.

NY_Mott · Aug 24, 2016

so my question would be; has anyone successfully ran oil to each valve cover like has been mentioned before in other posts using an oil bypass system?

I'd like to think if it's such an issue someone would have developed a way to prevent premature failures.

Real interested in what Airfish says on those HD updates.

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DEEZUZ · Aug 24, 2016

id say the average milege for these wearing out is about 125k. figure you put on a new set at that milege, you wont need to put on another set. theyll outlast the engine and more than likely your ownership. I dont see a reason to try and do a 6.7 type oil system on them. change em once and be done

NY_Mott · Aug 24, 2016

Right on, that's good to know.
I've just read it mentioned several times .

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DEEZUZ · Aug 24, 2016

i believe the updated rockers are nothing but a hole drilled into the tip part... I do not think any material was changed. from running many of these with VC's off, they seem to get plenty of oil. I believe most of the issue is how caked the oil can get in these with the regen and people just not changing the oil at all. Out of all the motors ive been in, 6.4s seem to MURDER the oil in the worst fashion. I have guys that sware they change it 5k and yet it stains my hands like ink... i contribute this to the very high blowby all of these motors have. lots of carbon getting into the crankcase

Rubenk · Aug 30, 2016

CTC DEEZUL said:
i believe the updated rockers are nothing but a hole drilled into the tip part... I do not think any material was changed. from running many of these with VC's off, they seem to get plenty of oil. I believe most of the issue is how caked the oil can get in these with the regen and people just not changing the oil at all. Out of all the motors ive been in, 6.4s seem to MURDER the oil in the worst fashion. I have guys that sware they change it 5k and yet it stains my hands like ink... i contribute this to the very high blowby all of these motors have. lots of carbon getting into the crankcase

Its really surprising how many run the cheapest oil they can get in these things.

Not to be a Jim/LE nutswinger, but I only ran it about 2k miles before opening the valve covers to do pushrods and springs and my 185k mile valvetrain was the cleanest my mechanic's and I have seen with that mileage! They both bought buckets of LE oil after that project.

sideactiondiesel · Aug 30, 2016

The simple fact of noone wants to change their oil is most of it. Poor lube circuit is also not helping it's longevity.

Jomax · Aug 30, 2016

sideactiondiesel said:
The simple fact of noone wants to change their oil is most of it. Poor lube circuit is also not helping it's longevity.

X2. I've had my uncle change his 6.0 oil at 35k miles. And the last place to do it was a quick lube so you know it was cheap oil...... I was surprised the thing ran.

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jdgleason · Aug 31, 2016

Shooting from the hip but I would guess 6.4s also have more seat pressure than a 6.0 since they see higher boost and back pressure...

TyCorr · Aug 31, 2016

jdgleason said:
Shooting from the hip but I would guess 6.4s also have more seat pressure than a 6.0 since they see higher boost and back pressure...

For sure. And it has to be contributing to the increased wear/decreased service life.

wcso873 · Aug 31, 2016

Rubenk said:
Its really surprising how many run the cheapest oil they can get in these things.

Not to be a Jim/LE nutswinger, but I only ran it about 2k miles before opening the valve covers to do pushrods and springs and my 185k mile valvetrain was the cleanest my mechanic's and I have seen with that mileage! They both bought buckets of LE oil after that project.

Whats LE oil?? If it's that good I'd like to check it out.

" Jesus loves you" a wonderful thing to hear in church. A horrific thing to hear in a Mexican prison...

78f100 · Aug 31, 2016

wcso873 said:
Whats LE oil?? If it's that good I'd like to check it out.

" Jesus loves you" a wonderful thing to hear in church. A horrific thing to hear in a Mexican prison...

This is who they are talking about, he changed names recently.
http://www.powerstrokearmy.com/forums/forumdisplay.php?f=211