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Hey All,


Not always but fairly often when I start my 5.7 liter R/T I will here the lifters rattle for a second or two... is this bad?
 

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If it goes away quick like that, probably not.

Curious - Do you do a lot of short starts/runs on the motor or pull the dipstick and check your oil often?
 

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Are you using full synthetic oil? That seems to help keep the Hemi quiet. I have been using Mobil 1 in my 6.1 2009 SRT for years with no issues.
 

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If it goes away quick like that, probably not.

Curious - Do you do a lot of short starts/runs on the motor or pull the dipstick and check your oil often?


Actually I do check the oil often, could that have something to do with it?
 

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Actually I do check the oil often, could that have something to do with it?
While I can;t prove anything, I used to check my oil a lot(just kind of an old habit even though it never needed adding) and I used to get ticks on start up after I did it. Perhaps there is a pressure loss and the lifters settle down? Could be all it my head, all I know is it almost always used to tick on startup after I checked my oil. I finally stopped checking it so frequently and I hardly ever have any ticking on startup...unless I turn it on and shut the car off shortly after. Even with that now it only ticks occasionally.

An occasional tick on startup that goes away quick is normal for every modern Hemi car I have ever owned.
 

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While I can;t prove anything, I used to check my oil a lot(just kind of an old habit even though it never needed adding) and I used to get ticks on start up after I did it. Perhaps there is a pressure loss and the lifters settle down? Could be all it my head, all I know is it almost always used to tick on startup after I checked my oil. I finally stopped checking it so frequently and I hardly ever have any ticking on startup...unless I turn it on and shut the car off shortly after. Even with that now it only ticks occasionally.

An occasional tick on startup that goes away quick is normal for every modern Hemi car I have ever owned.



Thanks Eric! I wasn't too terribly worried as I know it can take a sec for the pump to send oil up top but never noticed the sound on my chevy or my f150... also since ive had this challenger, a couple times my arm pushed it over to autostick while sitting at the red light and then I wound the engine pretty high before I figured out what the hell I needed to do! Sometimes I think I might have hurt something....:surprise:
 

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Thanks Eric! I wasn't too terribly worried as I know it can take a sec for the pump to send oil up top but never noticed the sound on my chevy or my f150... also since ive had this challenger, a couple times my arm pushed it over to autostick while sitting at the red light and then I wound the engine pretty high before I figured out what the hell I needed to do! Sometimes I think I might have hurt something....:surprise:

If the engine experienced high RPMs cold this could (could...) result in noisy lifters. Generally an auto maker calls for keeping RPMs below some threshold (4K for example) until the engine is fully warmed up and it is not a good idea to ignore this.

Whether the noise you hear is from you winding the engine pretty tight at a stop light no one can say.

However, probably the high engine RPMs have nothing to do with the noise.

Nor does checking the oil.

What is most likely the case and this is common with all engines with hydraulic lifters is when the engine is shut down some valves remain open.This puts considerable pressure on the lifters of these open valves and almost certainly this will squeeze out some oil that is normally "trapped" in the lifter.

Upon engine start a few lifters are partially collapsed and while they'll quickly pump back up with no harm done in the meantime they'll make noise. This can take a second or too but it feels longer.

As long as the noise is short lived, and the engine doesn't manifest any untoward behavior, and the CEL remains off there is no real cause for concern.

You can probably reduce the tendency of lifters to make noise upon cold start by not running the oil for too long.

Vehicle usage along with engine run time plays a role in how contaminated the oil gets. In this context the primary contaminate of concern is water.

Short trips with resulting short engine run times means the oil gets contaminated with water -- this is normal -- but the oil doesn't get hot enough to boil out the contamination.

Water in oil lowers the oil's viscosity. It also increases the oil's tendency the oil's propensity to foam, which means there is more oil vapor to deal with. (A subject for another thread is what effect the increased oil vapor can do to an engine's oil consumption).

Absent the opportunity to drive the car long enough and under the proper conditions -- surprisingly a "high speed" run down the freeway generally results in the oil remaining cool -- to really get the oil hot (212F or hotter) in order to boil this water out of the oil all one can do is recognize the fact his usage of his car fall under "severe usage" and arrange to change the oil (and filter) more often.

I can tell you my experience with my other cars that seldom saw short trips with most trips involving minutes -- 30 or more minutes -- of engine run time is even after around 5K miles the oil was affected enough the engines were noisier than they were with fresh oil (and oil up to temperature)!

But if one's usage involves more short trips that long trips and if the climate where one lives and drives is very humid (or cold as is the case during winter months) 5K miles may be too long to run the oil given how quickly the oil can accumulate water.
 

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If the engine experienced high RPMs cold this could (could...) result in noisy lifters. Generally an auto maker calls for keeping RPMs below some threshold (4K for example) until the engine is fully warmed up and it is not a good idea to ignore this.



Whether the noise you hear is from you winding the engine pretty tight at a stop light no one can say.


However, probably the high engine RPMs have nothing to do with the noise.


Nor does checking the oil.


What is most likely the case and this is common with all engines with hydraulic lifters is when the engine is shut down some valves remain open.This puts considerable pressure on the lifters of these open valves and almost certainly this will squeeze out some oil that is normally "trapped" in the lifter.



Upon engine start a few lifters are partially collapsed and while they'll quickly pump back up with no harm done in the meantime they'll make noise. This can take a second or too but it feels longer.



As long as the noise is short lived, and the engine doesn't manifest any untoward behavior, and the CEL remains off there is no real cause for concern.


You can probably reduce the tendency of lifters to make noise upon cold start by not running the oil for too long.



Vehicle usage along with engine run time plays a role in how contaminated the oil gets. In this context the primary contaminate of concern is water,



Short trips with resulting short engine run times means the oil gets contaminated with water -- this is normal -- but the oil doesn't get hot enough to boil out the contamination.



Water in oil lowers the oil's viscosity. It also increases the oil's tendency the oil's propensity to foam, which means there is more oil vapor to deal with. (A subject for another thread is what effect the increased oil vapor can do to an engine's oil consumption.)



Absent the opportunity to drive the car long enough and under the proper conditions -- surprisingly a "high speed" run down the freeway generally results in the oil remaining cool -- to really get the oil hot (212F or hotter) in order to boil this water out of the oil all one can do is recognize the fact his usage of his car fall under "severe usage" and arrange to change the oil (and filter) more often.


I can tell you my experience with my other cars that seldom saw short trips with most trips involving minutes -- 30 or more minutes -- of engine run time is even after around 5K miles the oil was affected enough the engines were noisier than they were with fresh oil (and oil up to temperature!).



But if one's usage involves more short trips that long trips and if the climate where one lives and drives is very humid (or cold as is the case during winter months) 5K miles may be too long to run the oil given how quickly the oil can accumulate water.



This all makes sense. In light of all this information I don't think there is anything going on out of the ordinary with my engine. Thanks Rockstar! Btw... I wonder if you would have any thoughts on another thread I started in the "general discussion" "issues and problems" section entitled "engine bog" either way thank you for your help regarding this!:thanks:
 
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