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02LGT
08-22-2007, 09:54 AM
When i start up my car, there is a slight slap or knock in the engine (currently 59k miles - 2002 LGT). It's only there when the car is still cold (outside temp around 70deg.) The unusual sound goes away when the engine is warmed up. Any ideas? normal? I'm using Valvoline 5w-30 non synthetic. I change my oil every 3-4k miles. Subaru OEM filter.
dodik
08-22-2007, 10:05 AM
most likely you need valve adjustment
Huffer
08-22-2007, 10:15 AM
Piston slap. Try running a 10w30 oil and seeing if that settles it down.

I ran 5w30 in the BD (see sig) and last month I switched it to 10w40 - piston slap is gone entirely, and so has a minor oil leak.
02LGT
08-22-2007, 01:12 PM
So when the oil grade is recommended at 5w-30, it's still okay to switch things around? 10w-30 is fine? What grade should be used during freezing cold weather?
Huffer
08-22-2007, 01:18 PM
Your owners manual has the oil temp/grades in it, you can use 5w30 year round it's good for 40 below freezing, 10w30 and 10w40 are good for 20 below freezing (IIRC).

The main difference is the viscosity of the oil - how much of it clings to the surfaces when it's cooler - sometimes that's a blessing because it "fills" the gaps in the engine before the pistons have expanded enough to fill the cylinders.

It's not a huge gap, BTW, but metal on metal spinning at 700rpm or 1000rpm when cold can make quite a racket.
LegacyRob
08-22-2007, 01:49 PM
Take it in to your subaru dealer when it is cold to let them hear it, tell them it soulnds like your drivin a deisel jetta or something. I got a whole new block out of it for free. There is a defected block in that yr. I also have a 02LGT. Actually I took it in the first time and they replaced 2 pistons under warranty, but within 8 months the sound was back so the replaced the whole block. And there is no harm in trying.
02LGT
08-23-2007, 11:50 AM
It has close to 60k miles
would they still be under warranty? I have less thank 59k...with mods...its not stock...I have header and desnorkus
LegacyRob
08-23-2007, 06:48 PM
Not sure what they would say about the mods. When i had mine in it had over 60k miles. well it had 108000km but thats more that 60k miles. Never hurts to try. A friend of mine here in town has an 02 BH and they are doing his block as well.