At 6500 miles, the 1/2 ton gasser dropped a cylinder on the way home. I think it either broke a rocker shaft, or one of those special lifters failed and the valve is not opening. Anyway, it is missing badly and hammering pretty hard. I took it to the dealer, but have not heard back yet. This 5.3 is the all alum version. Don't know if that makes any difference. Will let you know the outcome.
The active fuel management is not working and the dash said that the stabilitrack was not working and traction control wasn't either. Weird.


:(

Sucks to hear that. Hopefully it's not something that will keep it down long.

That sucks, hope it's something simple. Pretty sure that the reason that the stabilitrack and traction control stopped working is due to the misfire fault found in the pcm, which puts the vehicle in failsafe mode and either loses communication with or disables the traction and stability control functions. Once the problem is fixed and the trouble data cleared the other lights/failures will clear also.

Any updates on this?

Well the truck has been at the dealer for 2 days and hasn't moved an inch. Went by there today, and noticed that they haven't even looked at it. One more day, and I will take it somewhere else. I told the guy that I earn my living with that truck (company truck). NOt sure he really cared all that much.

The more I think about it, I think it could be a failed lifter, that colapsed and is not letting the valve open. The Active Fuel Management is not working, so I wonder if that is because a lifter failed. Either that or broke a rocker shaft. I noticed the other day after it happened, I shut it off and I could hear the compression of the cylider bleeding off. It was seeping, leading me to believe that a valve was not opening as it Should. They promised they would have an answer for me tomorrow.

I will let you know.

seen a few NNBS with broken valve springs........

What does removing the screen out of the Mass airflow do?

Absolutley nothing lol....i too once thought it did something a couple of years ago then i put the screne back it and it seemed like it got better throttle response

I was wondering what his mods were in case the stealership wanted to claim something about the warranty being compromised.

Well, the verdict is in, and it seems I was pretty close on this one. The number one cylinder had a lifter collapes and would not open the valve. They have to remove the head to get the lifter out, and the head bolts are what is going to hold this process up. It was one of the AFM lifters that failed. Not giving me a warm and fuzzy that is for sure.
They are going to replace the push rod and rocker as well.
I hope I don't have this issue on the rest of the special lifters. This will get old.

Just saw this same exact thing on a truck today @ work. 13,000 miles. hmmmm.....

there have been approx 75 of these failures.... out of the thousands upon thousands out there.... it seems relatively minor..... but well just have to wait and see...

sorry about the trouble bro....i fyou were at our dealer we would have had you in and out in a day maybe day and a half tops :judge:

some dealers unfortunately just dont give a crap about customer service

How much damaged was done? I would of asked for a engine swap or something!

hope the cam isnt damaged

Getting bad as the tundra :drive:

Any updates???

i just had a freind come by today with a 07 4.8 singlecab truck what also sounds to be a failed lifter, we'll see what happens tomorrow.
do the 4.8's have AFM?

do the 4.8's have AFM?

No, they don't have AFM. Bummer on friends luck, though.