I have a 2001 XJ with a 4.0 I6 and AW4. Every morning when I start up the engine sounds more like a diesel for a few minutes and then after driving for a while it goes away. I wasn't sure if this would be hydraulic lifters or something else. The engine has 105,000 miles on it and doesn't burn oil as of yet. I change the oil + filter every 3000 miles. Oil pressure when driving is 40 - 50 psi and about 20 psi when idling. I do have a small oil leak and this may becoming from the rear pan gasket or the rear main seal. Any help/ideas appreciated.
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Engine Noise
- Thread starter Tryfan
- Start date
joe_peters
NAXJA Forum User
- Location
- Grants Pass, OryGun
If your oil filter has a nitrile rubber anti-drain back valve, instead of a silicone valve, the oil runs out and you have dry starts each day.
What brand of oil filter?
What brand of oil filter?
JJacobs
NAXJA Forum User
- Location
- Fort Collins CO
It's likely to be either piston slap or lifters. Piston slap goes away somewhat after a few minutes when the pistons heat up. Lifters aren't as heat sensitive.
As for the oil filter, that'd cause a noise that lasted a few seconds, not a few minutes.
As for the oil filter, that'd cause a noise that lasted a few seconds, not a few minutes.
heyhar
NAXJA Forum User
- Location
- PA (near Poconos)
I had lifters go bad in my '92 well before 100k miles. Replaced them at 130k, now over 200k, engine still sounds good. It started out tapping when first started in the morning, bit it would go away after a few minutes. After a while, it would tap at any time, come and go. Sometimes after a run on the Interstate, it would start to tap and the idle would get lumpy. Since I replaced them, it runs fine. Also, I replaced the rocker arms, as they were getting hammered by the bad lifters. Four of them were scarred pretty bad. I was told afterward that I should have replaced the cam also. I didn't, but it doesn't seem to have hurt anything. Maybe find a mechanic that's familiar with these engines, (one who doesn't have a boat payment due) and get a second opinion.
joe_peters
NAXJA Forum User
- Location
- Grants Pass, OryGun
What is your daily driving like--lots of cold starts, short trips?
Could be building up some gunk in the engine and clogging a lifter(s). You could try adding some Marvel Mystery Oil or try running a diesel motor oil like Shell Rotella.
Could be building up some gunk in the engine and clogging a lifter(s). You could try adding some Marvel Mystery Oil or try running a diesel motor oil like Shell Rotella.
joe_peters
NAXJA Forum User
- Location
- Grants Pass, OryGun
Gunk/MMO/Seafoam in the oil, just follow the directions on the container; or you can drain off a quart of oil and replace with a quart of ATF--NOTE: if you use the ATF trick start and let the engine idle about 20 minutes, but DO NOT drive it or rev the engine up, just let it idle.
Seafoam in the intake is to remove gunk on the valve stems/intake and combustion chamber carbon buildup, it won't effect the lifters when added to the intake.
Seafoam in the intake is to remove gunk on the valve stems/intake and combustion chamber carbon buildup, it won't effect the lifters when added to the intake.
CaliXJ
NAXJA Forum User
- Location
- Oceanside, CA
Kind of a hijack here. But whats the benif. or running Shell Rotella?
hightime81
NAXJA Forum User
- Location
- Holly Springs, NC
the Rotella is formulated for diesel engines and has more cleaning ingredients in it to help clear out the gunk.
CaliXJ
NAXJA Forum User
- Location
- Oceanside, CA
Ok now is this something that once you start using it, you have to stay with it? Or would 2-3 oil changes be cool and back to Mobil one synthetic? (it what i run now)
hightime81
NAXJA Forum User
- Location
- Holly Springs, NC
many people run it as their normal oil year round. it's cheap as hell, like 15$ for 5 quart jug at walmart. but if your already using synthetic, i would think you should already be in good shape...
i have been using MMO (exchange 1 quart of oil out during oil change and add one quart of MMO in) for the last 3 oil changes (3K miles at a time as usual) and it has about cleared out my sticky lifter
one thing to note though, the MMO gets in and does its job and then gets out. so after about a week or so, check your oil level, you will likely need to add 1/2 quart or so.
i have been using MMO (exchange 1 quart of oil out during oil change and add one quart of MMO in) for the last 3 oil changes (3K miles at a time as usual) and it has about cleared out my sticky lifter
one thing to note though, the MMO gets in and does its job and then gets out. so after about a week or so, check your oil level, you will likely need to add 1/2 quart or so.
CaliXJ
NAXJA Forum User
- Location
- Oceanside, CA
Yeah i tried the MMO for cleaning out my lifters. It actually made it sound worse while it was in there. I ran it for about 2 days and just couldn't take it anymore. As far as running synth. It gets pretty dirty quick! Thanks for the info. I think i've jacked this thread enough. :yelclap:
joe_peters
NAXJA Forum User
- Location
- Grants Pass, OryGun
The advantage to diesel oils is their high level of detergents and pressure qualities. This becomes more important for cold start/short trip vehicles and higher mileage vehicles as well as severe service such as off-roading.
FYI--Mobil-1 has some excellent diesel motor oils.
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