Lifter/valve? rapping on start

1999 GMC 2500 Crew Cab 4x4 67k miles

Just recently when I start the truck I am hearing a rapping noise and it seems to quiet down after about 10-15 minutes sometimes!! I just joined the forum and I searched the previous posts and anything I could find states that it goes away in the first few minutes.

I had planned on trading this in but now I am trying to decide whether I should fix it first or just let the dealer handle it. I feel like I should be up front with them if its quiet when I pull in.. There is no other problems with the motor or truck besides this new issue.

Question#1 What is most likely the problem? And how much should I expect to to pay to get this repaired. A friend of mine feels it should be all labor about 6 hours as the parts would be minimal.

Thanks in advance for any help/tips etc..

Paul

The fact that the noise does go away, even though it takes several minutes, is a good thing. Have you changed your oil and filter? What is your oil pressure reading? 67K is not alot of miles (providing the engine as been somewhat maintained) I also agree with you about being up front if you're going to sale or trade. That said you need to get it fixed or expect a low trade or sale value.

The fact that the noise does go away, even though it takes several minutes, is a good thing. Have you changed your oil and filter? What is your oil pressure reading? 67K is not alot of miles (providing the engine as been somewhat maintained) I also agree with you about being up front if you're going to sale or trade. That said you need to get it fixed or expect a low trade or sale value.


Thanks for the reply... I wasnt due for an oil change but I did have it done.. I had them put 10W40 in there instead of the 5W30 that they used last time.. They actually messed up and put the 5W30 in again but the Manager caught it and made them do it again - this time with the heavier oil and I haven't heard the noise since.. A buddy thought it might of been something foreign down in the lifter valve area that got flushed.. I am not sure what is going on with it..but its quiet right now..

I think you have what is called piston slap. Checkout this website www.pistonslap.com