Pistons Replaced At 400 miles

Just purchased a new Yukon last Saturday. I noticed a clanking sound in the engine so I brought it in to be looked at. It has been in the shop ever since. GMC said that it was two of the pistons that was causing the noise and needed to be replaced!! Not too happy about having the entire engine torn apart at 400 miles but I guess I have to deal with it. Any one else have the same issue??

derrickgh said:

Just purchased a new Yukon last Saturday. I noticed a clanking sound in the engine so I brought it in to be looked at. It has been in the shop ever since. GMC said that it was two of the pistons that was causing the noise and needed to be replaced!! Not too happy about having the entire engine torn apart at 400 miles but I guess I have to deal with it. Any one else have the same issue??

Click to expand...

:eek2: If that happened to my Tahoe, I would demand a new truck. Good luck...

I haven't heard of this before, sounds like a manufacturing issue, and would be rare as GM builds good truck engines.

Haven't heard of this lately, but some of the earlier LS series motors experienced some piston "slap" at startup...it wasn't affecting all motors and I believe they pretty much fixed the issue a couple of years ago?

Tha would be a rare issue indeed...bottom line is how they resolve it and treat you during and afterwards - all manufacturers have their issues, but some treat you better than others (GM needs improvement here, hopefully they continue to work on their customer service at their dealerships)

Well got it back today and here is the synapse...

Clanking noise under hood at idle #6.8 and 5 connecting rod to piston pin fit loose #6 was loosest. Also found other cylinder rod assemblies appeared to have burnt on oil on piston pin area. Duplicated customers concern and contacted area service engineer and concluded that it was a possible connecting rod to piston issue. knock noise was only present when engine was at operating temp and would come and go in 15-30 second intervals. Contacted tech assistance and found no similar cases but was advised to also inspect camshaft and found connecting rods at piston pin area on several appeared to have been hot. #6 was loose along with several others. Removed camshaft and inspected cam bearings, lobes, and lifters. Replaced all 8 rods and pistons on both banks. Cleaned and reassembled engine and reinstalled.

..so pretty much a new engine and happy that they replaced all 8 pistons instead of just the damaged ones. Hopefully that takes care of the issue because besides that issue I love the new truck!!!

I think you're issue was just a fluke as the GM truck engines are pretty solid.

I agree...must have been a late Friday afternoon build... :confused2:

With good maintenance you should get 400,000 miles out of that engine.