Dissappointed in the 350

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I always heard praises of GM's 350 V-8 while growing up, so when it came time to buy my own truck, I chose one with a good ol' 350 (a.k.a. 5.7L). It's a 1999 GMC, and with only 38K miles, I just had to get a
valve job and new valve stems. I changed the oil every 3000 miles and had all scheduled maintenance performed by the dealer. So much for GM's claim of "the most reliable trucks on the road." With new competition from Toyota and Nissan, GM sure seems to be moving backward in the truck market.
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"Ric Bednar" wrote

Your experience is the exception, not the rule with these engines. I've hardly even seen the heads off these engines...especially at that kind of mileage. And I've never seen valve jobs and and/or stem seals replaced at that kind of mileage. So you either got a bad one, or you or someone else is attempting to fix a non-existant problem.
Ian
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No, not valve SEALS - valve STEMS. He got new valve STEMS. Right after that they changed the bumper fluid.
~KJ/TLGM

mileage.
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Ric Bednar wrote:

I have never heard of those problems at that milage with that engine. Are you sure you did not leave a 2 or 3 off one end of the 38K miles?
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came
GM's
truck
Never seen one need any interior engine work at that mileage. Very strange. I have about 8 of them around here and none of them have less than 100K on them. The one in my van has 110K and still runs great. You may have gotten a Friday truck.
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Valve Stem Seals at 38K? Not only is that abnormial, that and a "Vavle" job at that milage would lead me to beleave some one put used cylinder heads on it. Newer fast burn or Vortec heads are not known for cracking. I have seen 1 pair that was. Each head from a different truck.
The only 350 heads that had cracking problems were 882 & 641 casting. I have a buddy that has 882's on a 12.5 to 1 compression ratio 350. He's put 50K on the engine since slaping it togher from parts laying around the junk yard. His problem is, he never cleaned the rust off of the vavles, and one has started to seize up when the truck sits longer then 3 months.
What cracks 350 heads, or any small block chevy heads, is being run while exceeding 260 degrees of cooliant tempiture. If you did that to your truck, and GM warenteed it, consider your self lucky. Warentees do not cover abuse. Charles
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I have a 1999 K1500 with 56,000 miles on it. Oil changed at 3 to 4 thousand miles, runs like new and uses no oil. Smooth idle, smooth power. Mine is the normal for a 5.7 liter Chevy. And has never been apart.
Brian

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A chev 350 is generally tired at 200K+ A nissan titian would be lucky to make it to 100K The japs make good cars but they don't have the redneck in 'em to make a decent truck.
~KJ/TLGM 1990 GMC FS Jimmy 350CUI TBI w/ 114K & only oil changes.

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I beg to differ ... Toyota has made excellent trucks for 20 years at least.
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least.
You mean red necks have been making toyotas excellent for the last 20 years.
~KJ/TLGM
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a
years.
No, I mean Toyota has been making excellent trucks. If they weren't excellent, parts would break more often and rednecks couldn't have as much fun.... sorta like with GM trucks! ;)
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No I shouldn't go see them. They should just go play there silly little gook games and leave my economy alone.
~KJ/TLGM

came
GM's
truck
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"KJ" wrote

gook
Hey KJ....you know what? If you want to dislike the Japanese automobiles that's one thing. There's no reason to start using racist language. I'm not a particularly politically correct person myself, but you really only show your ignorance and misplaced hatred when you use the term "gook". That term does not apply to the Japanese.
I also grew up in an Asian country, have many Asian friends, and other friends of all sorts of nationalities. Perhaps you don't know any people other then white Americans, but there are plenty of them around, and they have the exact same ratio of idiots to good folk as do white Americans.
The Japanese aren't destroying your economy, you guys are doing it to yourselves, your own government. Big business has to make everything affordable for you the consumer while being profitable, so they ship jobs overseas. Pretty simple math in a capitalistic society.
Plus, you guys (and so do we) are letting the people that run big business get a way with all sorts of crooked stuff. They should be thrown in the hoosegow for a "long" time.
Ian
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You are correct, anybody remember Enron?
Brian
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Did that happen this week? What's Enron?
:)
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Interesting that you would want to compare a 5-year old truck to the new crop of Nissans and Toyotas. Go back to 1999 and see what they used to import and tell me that they had anything even remotely comparable to a ChevyGMC full-sized...
That aside, the repairs you experienced are quite abnormal for that motor. In fact, I would have a hard time believing that even an severely abused 350 would need a valve job before 40k miles. Methinks someone is pulling the wool over your eyes.
Just exactly what symptoms were you experiencing that made your mechanic say out of the blue "Oh yeah, you're gonna need a valve job."?
Cheers - Jonathan

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maybe If you woulda went backwards In years you woulda been ok.I have always had great luck with older 1970 up stuff.
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Response to the many replies:
The GMC dealer did the work after several month of troubleshooting. At first, they thought the cause was the fuel injectors, so after 5 fuel injector flushes and continuing problems, they determined the valve guides needed to be drilled out and new valves put in. The dealer also said this actually is becomming more and more common for late model 5.7L engines. They've seen a significant increase in valve jobs, regardless of mileage. Unfotunately, mine was just one year out of warranty, even though I have very low mileage (38K is the correct odometer reading). The valve job fixed the problem, the engine is running great again, so it's safe to say this was the root cause.
I like Tony 70000's suggestion: stick with the earlier model trucks (~ 1970 :-) )
Ric Bednar wrote:

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Im a little hungover here so please bear with me. How did the dealer make th coralation between the injectors and the valves? Was the engine farting out of the intake? Did they do a compression test or a leakdown test? Why would the valve guides have to be replaced? Were the originals so badly worn out that they could not knurle the guides?

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