Cracked Valve Spring 6.0 Max Trailering

JAMESWILSON001 · June 19, 2009

Hello,

I have a 2008 Sierra Max trailinger package. Truck is driven very seldom, 2,800 miles since July 2008. Started the truck last Sunday and it ran VERY bad. Dealership says that a valve spring is cracked. Truck was broken in gently for first 1,500 miles and has been used as a tow vehicle for a 8,000 lb trailer since.

Dealer says all that was needed was to change the spring, GM would not even pay for the oil change. (this was third oil change since new.)

Should I be concerned about future issues? Is this engine prone to failure? Or. Is this just what the dealer says, a bad spring and I should not worry?

Thanks

Jim

Stevens03 · June 20, 2009

Most of them are pretty rock solid. I wouldn't worry to much. Does your truck have AFM? I've been reading more and more of these valve springs breaking, and it seems like it's on trucks with AFM. I'd consider getting it programmed off or custom tuning to have it turned off. GM won't do it, but it can be done with diablo or a custom tune once fixed.

Welcome to the site

brims · June 20, 2009

Most of them are pretty rock solid. I wouldn't worry to much. Does your truck have AFM? I've been reading more and more of these valve springs breaking, and it seems like it's on trucks with AFM. I'd consider getting it programmed off or custom tuning to have it turned off. GM won't do it, but it can be done with diablo or a custom tune once fixed.

Welcome to the site

Aren't the valve springs the same, it's just different lifters?

JAMESWILSON001 · June 20, 2009

Truck has AFM. I thought AFM collapses the lifters. If that is how it works, wouldn't that cause the valve springs to do nothing. Just sit there in an extended state, holding the valve up???

Thanks

Stevens03 · June 20, 2009

I know nothing,... but since AFM's came out in the newer trucks, I'm reading more and more about valve springs breaking.

JAMESWILSON001 · June 20, 2009

I dislike the AFM. What is the lowest cost method to disable it?

Thanks

brims · June 20, 2009

I think it's kind of stupid to be blaming broken valve springs on AFM if you don't have any idea as to what AFM does. I could just as easily blame the thin passenger side brake pads on the OEM tires.

To disable AFM you have to get a tune (Blackbear, Wheatley) or get a handheld (DiabloSport Predator) they are all int he same ballpark for price.

MS3DALE · June 20, 2009

I know nothing,... but since AFM's came out in the newer trucks, I'm reading more and more about valve springs breaking.

Yeah but I don't know if the AFM would actually have anything to do with valve springs breaking

hiline · June 20, 2009

I know nothing,... but since AFM's came out in the newer trucks, I'm reading more and more about valve springs breaking.

Yeah but I don't know if the AFM would actually have anything to do with valve springs breaking

Hmmm, I'd think only if most of the broken valve springs, were on AFM lifters

JAMESWILSON001 · June 22, 2009

Got the truck back. Drove it on Saturday and got a check engine light. Dealer says it is an intake leak, and no problem to fix. Seems to me that this is a lot of problems for an engine with less than 3,000 miles. Dealer says that there is no worry here just a few issues to work thru.

Anybody have an idea for a way to force a trade or new engine? Or should I just ride it out and see how the truck is years from now?

Thanks

Jim

Stevens03 · June 22, 2009

I only blamed it on trucks with AFM having the issue,.. simply due to the fact that the motors have Variable VALVE timing which would lead me to believe it could be part of the problem. Didn't hear of valve breaking till AFM came around

So you go ahead and blame your tires for screwing up your pads.

brims · June 22, 2009

I only blamed it on trucks with AFM having the issue,.. simply due to the fact that the motors have Variable VALVE timing which would lead me to believe it could be part of the problem. Didn't hear of valve breaking till AFM came around

So you go ahead and blame your tires for screwing up your pads.

I'm sure the mechanics on here could tell you about broken valve springs long before AFM was a twinkle in someone's eye. Blaming the pads on the tires is the same crazy idea. Hell, even some of the home mechanics can probably tell you about broken valve springs prior to AFM. Just because you never heard of it doesn't mean it isn't true.

I'm pretty sure that VVT is only on the 6.0L, and I think there has been 1 or 2 guys with broken valve springs on the 5.3L. VVT is not AFM. Neither of which would cause broken valve springs as there are many engines from other makers that have VVT.

Spurshot · June 22, 2009

Got the truck back. Drove it on Saturday and got a check engine light. Dealer says it is an intake leak, and no problem to fix. Seems to me that this is a lot of problems for an engine with less than 3,000 miles. Dealer says that there is no worry here just a few issues to work thru.

Anybody have an idea for a way to force a trade or new engine? Or should I just ride it out and see how the truck is years from now?

Thanks

Jim

Given only the two issues you've had, GM wouldn't do an engine swap at this point. Nor would the BBB have grounds for ruling for GM to do anything more than fix what you have. The BBB is what I used to force Chevy into buying back my 98 2500 after a yr of going back and forth to the dealers to fix a leaky rear axle seal that wet one of the rear drums and caused it to pull hard on braking, keeping me from towing horses with it. BBB asked if I had gotten the utility I purchased the truck for. I replied; it had not, and that was the reason for the ruling to buy back the truck. If your truck ends up having a history of chronic engine problems that GM does not appear to be fixing, BBB may rule for a buy back or other settlement that GM would adhere to. For me, the problem had 4 attempts over the course of a yr for GM to fix. They bought back the truck and paid for everthing except gas, oil, and insurance. That included paying for tax, license, and full purchase price with destination, etc..