What's the cost for all of the broken can shafts in Toyota 5.7s.

 

I have an '02 Ford Explorer Sporttrack (mini-pu bed) bought brand-new in 2002. It has the 4.0L SOC engine. (My mechanic says the joke in the Ford garage is that they call it a SOC because if it gets a hole in it, you throw it away! Not real reassuring, but I digress.)
In May of 2010, at about 100k miles I had a valve spring break. Ford repaired it for me for $543. Apparently they have a special tool for doing so that holds up the valve and allows them to replace the spring. Hmmm. Fortunately, the broken spring held the valve up and didnt allow it to drop down and hit the piston or score the wall. When they were repairing it, I asked them if it would be prudent to replace all the valve springs. They laughed and said no, I probably just got a bad one or something.
January 2011, at 133k miles, another spring broke. This time it was catastrophic. The valve dropped into the cylinder and put a hole in the piston. I have a mechanic working on rebuilding it to the tune of $2500. this includes replacing ALL the valve springs and the timing chain. He said the engine is very clean inside, indicative of the good life this rig has led, so it is worth fixing. Everything else about the rig also works and is undamaged, so I'm "springing" for the repair.
I also have a '94 Chevy Extra-cab K2500 PU, bought brand new in 1993. It has 265k miles on the old 350 engine and we had never been into the engine or tranny until November of 2011. We buy a rig with eveything we can get on it, take good care of it, and drive it until we wear it out. We finally had to put an engine in this truck in November as the old one flat wore out and wouldn't hold oil pressure any more. Up until that moment, it had never used more than 1/4 of a quart of oil between changes and had never missed a beat.
I say this to explain that my expectation of the Sporttrack is similar. I wanted it to go 200k (with regular maintenance and fixing the little stuff) before I had major engine work. I hope to get another 100k out of it after this engine re-build, but now I am wondering. I dodged a bullet with the first valve spring, but took the second one right thru the heart just over a year later! I feel like Ford has found a way to force an engine to break after a limited number of miles. I may be unreasonable in my expectation, but the Chevy doesn't owe me a dime even after replacing the engine. My next truck will definitely be a Silverado. With any luck, they'll bury me in it with just short of a million miles on it and me!

 

Correction, the first vavle spring went at about 115k miles, not 100k as I said above. I put about 15k/year on my primary rig, which is this Ford when it is running. Oil gets changed every 3k on all my rigs.

 

128,000 miles, never a problem, running smooth down freeway, exit ramp, engine instantly running ROUGH, like a burnt valve in the old days . . . . told everything from coil box to maybe new engine was in order . . . . Ford dealer charged me $95 diagnostic fee to tell me #1 cyl had no compression, wanted $250 to pull valve cover and look . . . . paid wrecker $90 instead to bring truck to neighborhood independent garage . . . $173 to replace valve spring, parts and labor . . . . never had or seen a broken valve spring in over 50 yrs driving . . . wonder if such is inherent in this engine . . . .

 

Braken springs are rare but not unheard of in just about any engine.