Rattle on Start Up

Markymark420

New member
Anyone ever experience this? It has only done it maybe three times in the 16k since I bought it. Don't know if its related to parking the jeep on and uphill slope (nose high) or what. Almost seems like its starved of oil for the first few revolutions, but oil level is always right where it should be. Jeep is a 2011 JKU rubicon with about 16k on the 3.8L. All oil changes have been done a the dealer.
 

Drumr90

New member
Um could just loosened up little. Sometimes it may happen now what i would do is start it and drive it around block to heat up then check manifold bolts to see if there tight. That should fix ur problem.
 

wayoflife

Administrator
Staff member
Really, this early? Even though it only happens maybe once every 2-3 months?

a rattle at start up is pretty common on a JK especially if it's kinda cold out and goes away once warm. as mentioned, most likely a cracked manifold or exhaust shield that broke a spot weld.
 

Drumr90

New member
wayoflife said:
a rattle at start up is pretty common on a JK especially if it's kinda cold out and goes away once warm. as mentioned, most likely a cracked manifold or exhaust shield that broke a spot weld.

Ye hed know more than id know lol
 

Ramasun

New member
It's not valve chatter? When I bought my 08 a year ago, it did that on every cold start. I switched to of all things, a Motorcraft (ford) oil filter that is known to have a very good anti drain back valve - 400s. Never had the start up chatter since.
 

Markymark420

New member
I'll check the manifolds this weekend and I think for my next oil change I'll try out that filter because it does almost sound similar to when i use to change the oil in my other cars without putting some oil in the new filter and started them up
 

Brian G

New member
It's not valve chatter? When I bought my 08 a year ago, it did that on every cold start. I switched to of all things, a Motorcraft (ford) oil filter that is known to have a very good anti drain back valve - 400s. Never had the start up chatter since.
I’m interested in trying something like this. What year jeep and do you have any idea on part numbers or anything?
 

cozdude

Guy with a Red 2-Door
I’m interested in trying something like this. What year jeep and do you have any idea on part numbers or anything?
I mean, it does say what year his Jeep was in the post you quoted……. Take that and try googling a motocraft oil filter part number
 

Brian G

New member
I was thinking maybe a lifter bleeding off
Ya that could be. In 3.6 pentastar, does it have cam phasers?

my 11 f150 does and this problem exists with it too. And it was a major costly endeavor to “fix”. (It wasn’t fixed just new parts waiting to go bad again). I don’t think ford ever did a good fix with the first gens of the ecoboost.

now I’m wondering if the 3.6’s have a similar problem.
 
Top Bottom