Hey, you can't have all of this fun without me!! VBG Seriously some of what is being said about piston slap is true. Piston slap alone is NOT a reason to tear an engine down and do a repair. Piston slap is in fact normal on a cold engine because aluminum expands faster than the cast iron engine block. if the piston is tight enough cold, it will be too tight when warmed up. Piston slap should a repair actually be indicated actually does not even mean that a piston needs to be replaced! If the problem is a collapsed skirt, it can in many cases be "knurled" and reshaped to take up the slightly excessive clearance. A knurled piston is one that has many tiny marks made into it's surface, that cause the outer edges of the mark to rise up. Sort of like the way a center punch makes a "crater" in a piece of metal. These two links give both a description of knurling, and an actual application. http://en.wikipedia.org/wiki/Knurling http://www.hastingsmfg.com/ServiceTips/international_v8_engines.htm Now the one big problem I have with this thread is the idea that $100 in parts, a saturday, and a twelve pack of beer is all that is required to make the noise go away. I do understand the perception that to the right person pulling and reinstalling a piston isn't difficult to do but the reality is to do it right is in fact much different. This is a job where a very simple mistake can cause a major engine failure after the attempt. Plus if it's 4WD just getting the oil pan off and back on will take up most of your staurday, and that's if you have a hoist. People have been successful simply replacing a piston(s) in chassis but not always successful at eliminating piston noise or slap. That's because the piston is only half of the equation, cylinder wear or taper could easily be coming into play, and I would leave those checks/measurements up to a qualified machinist. Plus we still have the little issue of pressing the piston pin through the rod. Very few shops have the equipment to do that, let alone DIY's. There are many traps lurking in this repair that can make the whole attempt go south in a hurry. One common trap is as simple as not torquing the intake manifold in the correct order! An incorrect torque sequence distorts the engine block, and that changes the line bore of the engine resulting in main bearing/camshaft bearing wear. The $64,000 question from there is, does the resulting wear end up causing the engine to actually fail? Sometimes it does, and sometimes it does not. Lastly, stroke length plays a role in piston slap issues. The longer the stroke, the more often a piston skirt has to be shortened for clearance issues. Cylinder block deck height and other design issues can also impact piston design. The longer that the skirts can be, the less likely it is that piston slap is likely to occur. Although think about it, the longer the skirts, the greater the piston mass and you start impacting engine efficiency due to inertial, and frictional losses. Plus you can impact RPM and horsepower. It's all an intricate dance that even the manufactures are not going to be perfect at every time. That's why we have tolerances, and some things (noises) are allowable even if they are not completely desireable.

As old as 88 Silverado is, its still pretty high tech. The first step is for a technician to address your trucks problem is to drive the vehicle and experience the symptom as you have described for (him/her)self, and then start testing from there. The last thing that you want to do is start guessing and throwing parts, and the next to the last thing is for me to write out a list of possible causes, which would be likely to cause you to start throwing parts (guessing). The seat of the pants feel that a seasoned technician has is one of the most valuable skills that they bring to work everyday. It takes decades to learn to a master technicians level, and the learning never ends, there is always something new to experience. I'd advise schedule time for a tech to drive this and do some testing, then go from there.

Yes my 2001 Montero Locked Up out of the blue while idling. No oil light whatsoever. I just notice it suddenly lost power as I was about to park it. Then engine died in a way like it locked. Tried cheater bar to turn engine no luck. Recently though I charged the battery full and it budge a bit so I turned again with a cheater turning opposite direction and it did. It turn about half way. There is hope the engine can be fix while on the vehicle. Maybe bad camshaft or broken valve spring which bent the vavle. Worn rod earing would have thrown oil light or any bearing that is worn. I may add too that I recently rebuilt the head myself so there is a posibilty I may have Installed the valve train rod backwards which would cause the oil hole not to line up causing oil starvation on the cam shaft, I did notice loud valve noise when starting the engine that diminish once it start but gets loud when raising rpm. I also want to mention it also had broke valve spring on piston 1 but I fixed it amd ran like a champ before it locked up in me.

Having same engine idle problems. 92 chevy Scottsdale 5.7L, 104,800 miles.Starts and runs great but, when it warms up setting in drive with foot on brake, the engine surges. Idles down then back up (like a stuttering). Sometimes, when driving between 35 and 40mph it will do a little hesitation, but when I give it gas it smooths right out. I have replaced TPS, engine temp sensor, plugs, wires, 02 sensor. new fuel filter, disconnected the EGR vac (No difference), tested MAP it is good. So,a few months ago I had a new Distributor put in, it seems this is when my problem started. No saying this is the cause, but yesterday when when starting it for the first time and after a min or so the distributor started make that sound again (bearing) after engine warmed up it stopped making the noise. So I m thinking I have a crappy distributor. And yes I put in a Carquest dizzy. Had no choice the 3 auto stores around here all have crappy after market parts so I thought Carquest was the better choice. So it looks like I will be replacing this dizzy with a AC Delco if I can find one. Maybe you guys can check you distributor for your problem. Hope my impute helps someone. any feed back advise is welcomed. Email me jdcron@wmis.net as I may not see your response.