How to check for sludge ?

[cobram at juno.com]

I only use Diesel specific engine oils too.  Don't want to beat a dead
horse,  this has been the subject of much scrutiny and investigation on
vintage and not so vintage motorcycle boards.  The additive packages
added to engine oil destined for passenger cars is concocted to protect
the new and sensitive emissions equipment on newer cars, and are not a
good choice for vehicles spec'd for oil which used to contain the full
additive package.  High-po, high compression and turbo applications as
found on our beloved Teutonic steeds correlates well to the concerns of
two wheeled Euro and Asian engines built to similar tolerances.  Some
motorcycle specific oils still have the full additive packages, but all
testing and lab results (some of the guys on the bike lists make the most
anal among Audi-philes seem like uncaring appliance owners in
comparison), show engine oil specified for diesel applications beating
out even the bike specific oils.

If you shop around and hit a sale or clearance, you can get it really
cheap.  Wally World can be your friend, I picked up 10 gallons of the
stuff  when the already cheap shelf price for full syn. Rotella had a
managers special tacked on, worked out to about $9 a gallon.  It
simplifies things too, I use it in everything in the fleet.  The bike
especially likes it, I change the bike oil every 2500 miles, but don't
toss the oil,  I use the semi-used bike oil in the lesser vehicles in the
family's fleet at oil changes and run it for another 5K.  

 
"Ed Kellock" <ekellock at gmail.com> writes:
> I'm changing the oil this week in two V8s and a 91 Avant.  This will 
> be my
> 1st oil change in a year.  I'm using Rotella 5W40 in the V8s (nice 
> gallon
> jugs, 2 per car please, and 5 bux cheaper than the corresponding 
> Mobil 1
> synth) and Mobil 1 10w40 in the 242k mile Avant (unchipped).
> 
> One V8 may have accumulated 10k miles over the past year.  The other 
> maybe,
> maaaybe 5k.  The same 5k for the Avant.  
> 
> Synthetic oils are supposed to allow longer change intervals, right?