On 8/25/2011 10:19 PM, Ed Pawlowski wrote:

"Teredo" wrote
Recently had the plugs changed, first time since new. Compression test
each cyl. All 6 (4.2L inline 6 Vortec 275 HP 10:1 compression ratio)
were within factory specs. Also use a Fram high density filter.
Oil pressure is 41 PSI at hot idle, 70 PSI at 2k rpm. The motor is so
quiet it's hard to tell if it's running. The factory 'change engine oil'
light comes on each 5k miles after reset. As far as I'm concerned that 3k
oil change rule is worth following.



Why?
My Buick was the same way, except I changed oil at 7500. In the 130,000
miles I had the car that would be 17 oil changes. Following your method,
I'd had had the oil changed 43 times and the results are the same. At
$30 a pop, I'm $780 ahead.

I imagine I could have kept it longer, but the car had other issues and
I gave it away to may grandson. Damned engine ran perfect though.

I've also owned a couple of Sonatas. The dealer (I don't use dealer
service in general) recommends fuel injection service every year for
$129. If I did that on all my fuel injected cars in the past say, 20
years, I've have spent thousands of needless dollars. I've never had an
FI problem. So, 2 cars at $129 for 20 years, the shop would have $5100
of my money and I'd have no gain.

Preventative maintenance is important, but should be done with sensibility.

Click and Clack call FI cleaning 'wallet cleaning'. Unless the engine is
running crappy, the injectors are already clean enough. Yeah, I know,
the computer compensates up to a point. Trip odometers are wonderful-
reset at every fillup, and if there is a change in MPG, it should jump
right out at you. When mine starts drifting down half an mpg or so, I
know it is time to dig out the compressor and top off the tires.

--
aem sends...