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Showing results for tags 'vortec 5.7'.
I have a 1999 K2500 regular cab with the 5.7 and 4L80E transmission, 285s for tires. I got 14mpg bringing it home, which was about 250 miles. I've been driving it around and I'm getting about 9-10mpg. I have read that an exhaust, cold air intake, and new 02 sensors. I plan on replacing all of the 02 sensors so I was wandering how many upstream and downstream sensors there? And is there any other ways to improve my fuel economy? Thanks
Well, awhile back I picked up what I was hoping would be a good deal. Craigslist ad for a 1997 GMC Sierra 1500 4x4, regular cab long box, has 180,000 miles and the listing said body and interior in great shape, would trust driving the truck to Texas and back, yada yada. So I made the 200 mile trip to pick it up, they were asking 1800$ and when I got there, rockers were rusted out, cab corners gone, windshield wiper motor fried, blower resistor bad so only 1 setting works, door hinges shot, trucks misfiring, low coolant, oil blacker then sin, starter cranks slow, broken mirrors on both sides, list goes on. Talked her down to 1400$, and somehow managed to make it back, of course I had to drive through a blizzard on the way back. Overdrive started shuddering extremely bad in lockup so had to throw it in 3rd gear the rest of the way. Now so far, I've replaced the injectors with the MPFI spider, new intake gaskets, new plugs (she had the wrong ones in it), new distributor, new cap & rotor, cleaned a shit ton of sludge out of the intake valley, new pulleys and new serpentine. Engine has a tick that is sometimes loud, sometimes quiet, on the driver side bank. Usually goes away once truck warms up. Its there at all RPMs, doesn't get louder or quieter getting on the gas, so guessing its a valve? Dumped a quart of ATF in, drove it some and changed the oil. Fresh oil now with a quart of Marvel in there, definitely an improvement. Oil pressure is 30-40 at idle. I still have a random misfire, not throwing any codes. And when I say random, its only once every 3-5 seconds that I will feel the misfire, not in any given pattern. Thinking plug wires? Haven't changed those yet, but figured I would see what others recommend. I was hoping the shuddering at 45-60 during converter lock up, was a misfire or something. Feels like damn rumble strips. Hoping I don't have to get the whole tranny rebuilt. Paid 1400$ for the truck, and put about 1400$ into it so far. Still needs a lot of things.