DODGE RAM FORUM banner

1 - 12 of 12 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
I have a 2015 ram, 5.7 with the 8 speed. When I start the truck after sitting a while it has an eratic knocking. Not a lifter or the hemi tick. Its a knock....knock knock..knock.......knock knock knock.....knock etc. When engine gets to normal operating temp it quiets down. Also when you rev it anywhere past idle it goes away. Driving me crazy! Help!
 

·
Registered
Joined
·
116 Posts
When you figure out what it is let us know, my 2016 6.4 in a 2500 Power wagon has a similar knock. My thoughts are either a rod , ( not sure if the 5.7 has this ) there is supposedly a flapper inside the muffler and it might be transmitting a sound back thru the exhaust somehow, or a very long shot is a noisy torque converter .
 

·
Registered
Joined
·
225 Posts
Me also, not a tick, or a lifter tap, but a loud knock at cold start up ,and only really loud when i shift into drive.? will go away when warmed up, and any other starts during the day no knock? Sit all night and morning knock is there? Have a flow master 40 series muffler new this spring??
 

·
Registered
Joined
·
410 Posts
Sure sounds like oil starvation of something. Is there any correlation with outside temperature upon startup? i.e. - during hotter outdoor temps does it knock less at startup? Is so, check for weak oil pump. Do you have EVIC display read out for oil pressure you can watch?
 

·
Registered
Joined
·
225 Posts
Never though of weak oil pump? When other start ups during the day either no knock or very little for just a few seconds then gone?
 

·
Registered
Joined
·
2,744 Posts
WEAK OIL PUMP OR EXHAUST BOLT BROKEN'
 

·
Registered
Joined
·
225 Posts
Exhaust bolts replaced. Sounds like it is coming from the trans area? Is there any info. in these forums about weak oil pump?
Thanks
 

·
Registered
Joined
·
425 Posts
Exhaust bolts replaced. Sounds like it is coming from the trans area? Is there any info. in these forums about weak oil pump?
Thanks
Possible loose converter bolts although that wouldn't change when warm.Sometimes if an engine isn't exactly hitting on all cylinders evenly it can also sound like an engine knock as well.This could disappear when up to operating temps.
 

·
Registered
Joined
·
225 Posts
Runs very smooth with no misses on warm up? If i start cold and run about 5 min. then turn off for 5 to 8 min. new start up very little knock, when shifted into drive, and none at full warm up?
 

·
Registered
2014 345ci 8hp70 44-44 3.92 Truetrac
Joined
·
1,464 Posts
It’s 2020, take a video guys. One’s knock may be another’s tick/tock/slap...
 

·
Registered
Joined
·
3 Posts
Discussion Starter #12
So after more listening I found that it doesnt do it on first start up but when the temp gets between cold and normal temp. First start up nothing, as it warms up a bit it knocks erratically. Then when it gets close to normal operating temp it goes away.
 
1 - 12 of 12 Posts
Top