Agreed, I've torn down a few engines that "flush" was used and put everything in the pan cloging the pick up screen causing bearing failure.

I run Rotella 5-40 syn in all my vehicles except my MG which get's 5-50 Syntec. If you look in the oil fill on any of my vehicles they look like the day they rolled off the assembly line and like I said it comes out a nice amber color. Rotella can be had cheap at Wallymart or Autozone in gallons or "Farm" stores in 5 gallon buckets. I do 3K mile changes in my Saabs due to the high boost I'm running and known sludge issues. My good old push rod American V8 truck with over 300K I go to 7K, but change my filter every 3,500 miles.

 

what SAABs do you have?

I've had:

95 two stroke
2 96 V4s
Sonnett III
several 99s
Several 900 Turbos
was thinking of a newer 900 Turbo like a 1996, but, not sure

 

Awesome cars that will put a smile on your face everytime you turn the key. Modds are easy and cheap compared to rice and the engines are so over designed until you hit 2000 on the 9-3's that you can push them hard and still have them reliable (relative term).

94 900s coupe
stg 2 1998 900se vert (wifes)
stg 5+ 1999 9-3 (it's my DD pushing 26psi boost with a 2.3 stroker engine I built out of a 9K Aero in it. I'm going back on the dyno in a few weeks for some new numbers. Last run at 18psi was 283whp and 298wtq by 5500 rpms. I recently upgraded the turbo and tune and no longer have taper at the top end. I should be mid 300's at the wheels. It's a handfull but still gets 19-21mpg with mixed and 31-33mpg on highway trips. Except for the 4" tip on the full 3" exhaust it looks stock.

 

I agree with the previous post that if you don't mind the extra up front costs of synthetic motor oil, it's definitely a better way to go. I use Mobil one in my Caddy and in my lawn mower. The garden tractor is coming up on 10-12 years old, now. My lawn is appx 1.5 acres of grass. I've mowed a whole lot of grass over the years and the motor still runs great, doesn't burn a lick of oil. And, yeah, it looks like new inside. I think on a small engine that doesn't typically last as long, you can really see the positive effects of running synthetic.

I've known guys over the years that had company vehicles where they ran synthetic (company was paying for it), they would get very high miles and motor ran like new at the end. Jeez ...maybe I should be using it in my Disco too...

 

sythetic is the best as long as u dont have a bad oil leak. i only use mobil 1 10w30 and wix filters at my shop unless the customer asks for different

 

Green Machine - you mentioned "If you look in the oil fill on any of my vehicles they look like the day they rolled off the assembly line and like I said it comes out a nice amber color."

I am definitely been trying to get to this state... had the truck three years, bot it with 50K miles on it, just turned 80K.... been changing the oil religiously every 5K.... did an ATF flush when I got it... and run 10-30 Mobil 1 synthetic... I use the K&N filters as well

You think that switching to Rotella would get the rest of the gunk out of the engine? every time I look in the fill tube, I hate to see some of the gunk in there..... All the PCV valves are clean, etc...

 

Also, anyone used Auto-RX on their Disco to clean sludge? www.auto-rx.com ?

Results or experiences, good, bad, or otherwise....?

 

Sorry, it took a while to get back to you. My Disco's not to this point yet as it's new to my fleet and maybe their not capeable (others will have to chime in). I'm not a big fan of "cleaners" because I've seen engines destroyed by them from them doing their job then blocking the pick up screen in the pan. I have and do use them, but only if I intend to pull the pan and clean up. Some vehicles due to PCV "short falls" can never reach this state (Saab T7 engines without the PCV upgrades, it causes sludge and eventually failure). I also had a Lincoln Mark 7 LSC that was just horrible with sludge and coaking!! If I haven't owned a vehicle from new and it's a higher mileage one, I'm wierd enough that I usually pull the pan and clean up as well as look for anything unusual (pieces of plastic from chain guides and pieces of bearings are always nice surprises).

 

It used to be the popular miracle additive over at bob is the oil guy and then as more people started to use it, it became apparent that is is not all that it is cracked up to be (especially for the cost). They say it has trouble with cleaning varnish off aluminum due to the porosity. It definitely will clean but results vary. The best cure for a truly sludged engine is to drop the pan, front cover and pull the cylinder heads and clean them.

Do you have sludge? How do you know? These engines varnish up pretty badly but that is mainly cosmetic. You have to really abuse the engine with long dino oil change intervals to get sludge.

 

Good question on the sludge.... how do I know? I haven't dropped the pan, so I don't know... and in fact, I think it's actually pretty good, as evidenced by switching to Synthetic at 55K miles when I bot the car.... and the oil staying relatively light colored (Mobil1 10-30 synth) over the course of 5K miles.

I see some sludge when I pull the PCV hose and look in there, as well as when I look in the oil fill spout....

I happen to have a can of Auto-RX and was thinking, why not use it...

Perhaps an adjunct question is that I smell what seems to be like a 'gassy' smell when I put my nose in the oil fill cap... is that just the gases scavenged by the pcv system, perhaps a bit of blow by on the the rings?

Any tricks to do a compression test on this? I have all the tools and like to work on it... do folks just typically pull the fuel pump fuse? anything else?