quote:
Originally posted by TooSlick:
The 4.3L, Vortec V-6 is not well suited to extended drains, due to fuel contamination and high rates of oxidation/nitration. I would strongly advise oil analysis if you want to extend past 7500 miles, even with ASL or ATM ...Pull up all the UOA's and you'll see what I mean.
Yep , absolutley correct.
I would never advise to beat the EGR valve shut on a 4.3
but to continue this topic :
Considering these motors also consume a bit of oil at above 5k miles " probably due to using dino's that thin down " do the Amsoil guys agree this might be viable where these vehicles live .
To try for annual changes starting the intervals Dec 1 , my favorite Amsoil
Groovy 10w-40 for this application will be fresh and should work well in the pushrod motor through winter if they stay running most of the day and by late spring they should be a quart low , top-off and spin new O/S filter " have employee do it in lieu of lube center " and go with it . The cost would be 7 quarts of oil annually if it worked out , small additional if the motor burned more .
This really is a tough motor oil and these motors are tough on oil . We've gotten awfull picky with our wear numbers here but surely this oil would keep Iron below 50ppm , lead below 30 ppm or therabouts should it not ? I'd be happy with that considering these vans are not keepers.
EDIT for 10w-40 testimonial
A clueless friend of mine in terms of motor oil and the heaviest procrastinator for doing oil changes I've ever met bought some of the 10w-40 a couple years back and used it in a 5.7 Chevy " 1997 model " that had spent all it's life on dino . No flush , that tiny little filter those use and when we got together for our annual X-mas deal I asked how long the oil was in . He could not figure exact miles but it was at least 8k and a whopping 13 months if memory serves correct! No lie, I did a field test and it was still motor oil in there
. He said it used one quart . I don't see him often , last spoke he had returned to using dino.... the dummy considering his oil change habits or lack of
He should have bought some more .
[ February 21, 2004, 06:03 AM: Message edited by: Motorbike ]