Topic: Knocking noise on 2001 GM Sierra

[shaq]

Allright panel here's one for you.I was on a sight called Lemonaid and the big headliner was "GM sued by Customers". It was regarding the knocking noise in the engine on start up.It would then go away after a couple of minutes because of warm up of course.The article went on to say that GM had replaced over 100 vehicles because they could not fix the problem. I have the same problem with my truck. It sounds like it should be a recall or something that they should be fixing themselves for nothing.Could you lead me in the right way of what to do in this situation? All the motors they are talking about are the 4.8 & 5.3 and mine is a 5.3.

[barrie1]

I remember the 305's haveing a knock from the factory which was quite a problem for them. I haven't heard too many bad things about the 4.8 and the 5.3's as yet. I know of some with over 300,000 klms on them and still working very hard. I suspect GM would rather replace the engine 1st because of the cost as long as there is warranty left on the vehicle. To replace the entire vehicle is very unusual but has been done by some of the Builders.

[Drivesideways]

The story you're refering to is over a year old.  And the site you read it on (or found it linked from, anyway) is a law firm that specializes in lemon laws in the states so beware of their motives.  Since this is an American story, I'm not sure what the implications are in Canada.  It sounds as if those owners that GM bought trucks back from had been very persistent in pursuing resolution most likely starting with their dealerships.  If the knocking is a concern and you haven't already done so, start with your neighbourhood Goodwrench guy.

[maritime_storm]

What we're they replaced for Piston Slap or Bearing Knock? Memory serving me correctly it piston slap that 305's suffered from and GM did very little about it. I'll second Barrie's comments about the 4.8L{283},5.3{327}, 6.0{368} engines, they've been the first really durable & trouble-free V-8 engines Chevrolet built in alot of years. Mind you the 305 & 350 improved remarked throughout the 90's, but new series are far better still.

[barrie1]

Yes Maritime it was piston slap in the 305's and a few 350's as well. A Friend of mine went thru this the 2nd week of ownership at the time and they put 4 new engines in it in 4 days. Every one had the same problem within minutes of being installed. The Dealer tried to tell my pal this was normal, He's a licensed GM Mechanic who specializes in Big Block Racing. He received a special tradeIn allowance a year later and used it on a new one.