Good Write up On 5.7 Hemi Issues

[domer10]

Originally Posted by fdcg27

Originally Posted by domer10

Originally Posted by Skippy722

Originally Posted by Sunnyinhollister

I thought the 6.4L Hemi uses the same lifters as the 5.7L, however the 6.4L specs a 0W-40 viscosity and the 5.7L calls for a 5W-20.

They do. The "5w20 or else!" thing is complete nonsense.

And get a bag, or something that holds liquid, now cut a hole...now put thin liquid and push it through...then do same with thicker fluid, let me know the pressures required to get the thicker fluid through that hole. Like it's common sense and people want to create a argument. I will take his word over someone random on a forum who thinks it's not true because he doesn't believe it.

Okay, so what's supposed to happen when someone goes out and starts his pickup on a cold morning? The 5W-20 is then thicker than a 10W-30 would be on a warmer morning. This is the reason that I don't think this theory has any validity. Viscosity is always and everywhere a function of temperature and it doesn't take any great reduction in starting temperature for a 5W to be thicker than a 10W. Next up theory?

Ok so it's thicker for all of what, a minute? Instead of running that thickness for months on end. Yours is just as invalid.

 

[bdcardinal]

Just curious, as my knowledge of the newer Hemis isn't all that much. Are they all built in the same factory? Meaning are the 5.7 and 6.1/6.4 built on the same line or is there more of a niche line for the 6.4 engines like Ford does with the 5.2L? It could be that the part numbers are the same on the service side but the lifters are sourced from different places for the factory assembly?

 

[Skippy722]

Originally Posted by domer10

Originally Posted by Skippy722

Originally Posted by Sunnyinhollister

I thought the 6.4L Hemi uses the same lifters as the 5.7L, however the 6.4L specs a 0W-40 viscosity and the 5.7L calls for a 5W-20.

They do. The "5w20 or else!" thing is complete nonsense.

Not sure where he said 5 20 or else, as he said this is his theory.....which makes complete sense, he states 10 30 and probably means above that. But what what a NASCAR engine developer know.

Manuals used to state "NOTE: Vehicles equipped with a 5.7L engine must use SAE 5W-20 oil. Failure to do so may result in improper operation of the Multiple Displacement System (MDS)." even though the MDS system is identical in the 6.4, which specs a 0w40. Hence my "5w20 or else!" quip. Your engineer stated "First, these lifters control lash hydraulically and are designed for 5W20 oil." which clearly isn't true, because if it was then there would be all sorts of issues with the 6.4, being the same lifters and all.

 

[domer10]

[

Originally Posted by OVERKILL

Originally Posted by domer10

Originally Posted by OVERKILL

Originally Posted by domer10

And thanks for the info on the 6.4.

No problem! If this topic interests you, you'd probably REALLY enjoy the other thread.

It does! could you please send link? Or is it already in previous post?

It's not, let me dig it up, give me a few.

Also what year did the 6.4 come out? I thought early challenger had 5.7 as well just beefed up? Or was it same as truck engine and just geared different?

 

[OVERKILL]

Here's the thread. I'll preface this with a warning that it is LONG and unfortunately the oil system diagram pic I linked was removed, I'll go back and see if I can find another copy of it if you want to see it. https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/5122632/1

 

[OVERKILL]

Originally Posted by bdcardinal

Just curious, as my knowledge of the newer Hemis isn't all that much. Are they all built in the same factory? Meaning are the 5.7 and 6.1/6.4 built on the same line or is there more of a niche line for the 6.4 engines like Ford does with the 5.2L? It could be that the part numbers are the same on the service side but the lifters are sourced from different places for the factory assembly?

IIRC, they are both built in the same plant in Mexico. No idea who the supplier for the lifters was/is.

 

[OVERKILL]

Originally Posted by domer10

Also what year did the 6.4 come out? I thought early challenger had 5.7 as well just beefed up? Or was it same as truck engine and just geared different?

SRT's always had a different engine. It's covered in the thread I've now linked mentioning the 6.1L (which came before the 6.4L) as well as the current 6.2L Hellcat engine.

 

[domer10]

Originally Posted by OVERKILL

Originally Posted by domer10

Also what year did the 6.4 come out? I thought early challenger had 5.7 as well just beefed up? Or was it same as truck engine and just geared different?

SRT's always had a different engine. It's covered in the thread I've now linked mentioning the 6.1L (which came before the 6.4L) as well as the current 6.2L Hellcat engine.

Thanks Boss! Give me some nice reading, as I am looking at putting a SRT in the stable!

 

[OVERKILL]

You are quite welcome!

 

[Ws6]

I had near 100k miles on my 2010 5.7 with mds. It ran like I sewing machine. Rest of the Jeep was junk, but engine was good.

 

[demarpaint]

Originally Posted by Skippy722

Originally Posted by Sunnyinhollister

I thought the 6.4L Hemi uses the same lifters as the 5.7L, however the 6.4L specs a 0W-40 viscosity and the 5.7L calls for a 5W-20.

They do. The "5w20 or else!" thing is complete nonsense.

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