GM Truck Club Forum banner

1 - 1 of 1 Posts

2 Posts
Discussion Starter #1

Truck - 99 Suburban, K1500
History - In the last few months I have been trying to figure out an inefficient cat code on the even side. I towed the boat to the lake 6 miles away, then climbed under to check cat temps with an infared. While under there I heard a ticking. On the way home it died at a stop and was difficult to restart. It ran ok the rest of the way home, but did not push it towing 4,000 lbs. By the time I got the boat back home later in the day, it was a louder ticking and a screeching/squeaking developed that drowns out the ticking. After listening above and below, I suspect it is a bearing in the block. Tonight I am going to pull the belt to make sure it is not a pulley or accessory on the front. A compression test on the even side showed 155 in #6 and 8. I assume that indicates a blown gasket between the two. This would make the output rich from unburnt fuel, which would account for the Cat code. The bearing and tick noise seem to be related to each other and unrelated to the compression issue. They both increase with RPM. Neither changes under load.

Any ideas on what to check and how to complete the troubleshooting prior to pulliung the engine apart? I have a video that contains the noises, but can’t post it here that I see. Thanks in advance!
1 - 1 of 1 Posts