When Temp is about 45 degrees F or below, engine makes a knocking noise for a while then stops. I don't have this problem when the weather is warm. It doesn't seem serious but I'd rather get in front of the problem rather than have my engine break down. Thanks for your input
2007-01-16 11:20:56 · 7 answers · asked by chhintz 2 in Cars & Transportation ➔ Maintenance & Repairs
It's actually common on the GM motors, there is too much play between piston and cylinder. the piston expands when warm and then all is good and tight. GM calls this normal, that sounds like a long time, not much you can do. Do your oil changes regularly and hope it doesn't get worst.
2007-01-16 11:32:23 · answer #1 · answered by wheeler 5 · 0⤊ 0⤋
This is common with any GM product. The shirts on the pistons are so short that you get piston slap when the engine is cold.The only fix is to replace the piston GM did come out with updated piston to help this trouble but yours may already have these pistons in it.If you can plug your truck in at night this seems to help.If not if it still under warranty try it but most dealers say it just how those engines are. Good luck hope I helped
GM tech for 20 years
2007-01-16 11:29:52 · answer #2 · answered by Rudedude 4 · 0⤊ 0⤋
your oil is thicker this time of year from the cooler weather,also most newer chevys from 99 up are doing it.if it has high miles just start it and let it idle,and you might want to go to a lighter weight oil.i have ran into having to clean the pistons with a machine that most dealers have,to clean the carbon off the top of the pistons,the carbon will build up and start making contact with the head and the pistons till after warm up.
2007-01-16 11:27:54 · answer #3 · answered by strange_busaman 3 · 0⤊ 0⤋
most time it is lefter noise how Meany miles has your truck got on it if low miles i would not fr eat over it but if it has got a lot of miles i would have the valve train run to see if Any rocker arms are out of adjustment. Most would say put in a can of STP or oil treat meant but that is like putting a band aid on a knife wound. but still not nothing major going wrong with your motor. Good luck.
2007-01-16 11:30:51 · answer #4 · answered by master of none 3 · 0⤊ 0⤋
Try 5W20 Mobile !. It will flow better in cold weather.
2007-01-16 12:08:37 · answer #5 · answered by Nomadd 7 · 0⤊ 0⤋
Use an oil that is thinner so the pump will pick it up.
2007-01-16 11:38:14 · answer #6 · answered by Anonymous · 0⤊ 0⤋
4.3 get used to it the dealership told my dad they all do it its normal. call to verify
2007-01-16 11:28:58 · answer #7 · answered by Sheldon B 2 · 0⤊ 0⤋