Severe Sludge - Saab 2.3L

[Joel_MD]

I have a 2003 Saab 9-5 Linear with 2.3L turbo I-4. The car has 147k miles on it, but I've only owned it about 16 months and put maybe 10k miles on it. I believe the previous owner had it serviced at a Saab dealer. I know from some online Saab forums that this engine has a tendency toward sludge buildup. I had the car in for some suspension work last week and also had the mechanic drop the oil pan to check for sludge. This mechanic is very experienced with Saabs. He showed me some cell phone pics of my oil pan and said the sludge was about as bad as he's ever seen. The oil pump pickup screen was nearly blocked, with a big cone-shaped formation of sludge directly under it on the pan. Anyway, a case of brake cleaner later it's clean, but the mechanic said he's seen engines like this that develop an oil starvation problem a few months down the road after cleaning up the sludge. He recommends changing oil at 2k mile intervals the next couple of times, and perhaps dropping the oil pan again after a year or so to check/clean.

I know the folks on the forum tend to not be bashful about sharing their opinions. What do you recommend I do to minimize the future effects of sludge in this engine? BTW, I'm using Mobil 1 0W-40 and a Hastings LF134 filter, which is oversize for this application.

 

[J_R]

Make sure the PCV update kit has been installed.

 

[Joel_MD]

Originally Posted By: J_R
Make sure the PCV update kit has been installed.

Yes, the latest PCV update kit had been done by the Saab dealer.

 

[Olas]

If the PCV and the coolant system are both top-notch, I'd be tempted to do a couple of 500 mile oil&filter changes to assure myself that every last bit of sludge and goop has been removed and then go to a 3k change on HDEO with a yearly check under the valve cover and inside the sump.

A bypass filter can remove the particles that are too small for a regular filter too catch, and some say that these particles are the precursor to sludge

Do the chemists on here know which oils best resist sludging/oxidation/thickening? Redline is thought to be very good in these regards but some consider it too expensive. Others with high detergency like Delvac and Rotella would help with cleaning but I'm not sure how they fare in a high specific output turbo engine that sees high RPMs, I thought they were more aimed at low revving diesel motors?

 

[ISO55000]

If I may

I would recommend doing a little analysis and determine the root cause of turning the oil into sludge in what is described as something not quite standard.

The reason I say that is because I have had clients who “try” all kinds of “stuff” guessing and spend hundreds of thousands of dollars before I ever hit the door. (Firms like us are always the last resort, LOL)

If you are experiencing “premature” or even “excessive” sludging that is not considered “normal” then isolate the agent(s) that are making it happen.

Is this a known condition of this particular engine and no other?

Is it more or less susceptible with different oils?

All kinds of things to look at and for
You may find a combination solution (changing oil and change interval), maybe a mechanical fix, maybe it is a result of an inherent design- you just don’t know.

I recommend going that extra step because if you don’t you are addressing the symptom rather than the root cause so unless you accidently get lucky you can spend a lot of needless money and never really get satisfaction.

It’s cheaper in the long run.

 

[Rand]

just don't use any additives if they break up any of the sludge to fast it will clog something. Normal high quality oil at reduced intervals is the best IMO.

 

[SwampSurvivor]

I'd run a few short intervals with a cheap HDEO.

 

[Joel_MD]

Originally Posted By: ISO55000
If I may

I would recommend doing a little analysis and determine the root cause of turning the oil into sludge in what is described as something not quite standard.

The reason I say that is because I have had clients who “try” all kinds of “stuff” guessing and spend hundreds of thousands of dollars before I ever hit the door. (Firms like us are always the last resort, LOL)

If you are experiencing “premature” or even “excessive” sludging that is not considered “normal” then isolate the agent(s) that are making it happen.

Is this a known condition of this particular engine and no other?

Is it more or less susceptible with different oils?

All kinds of things to look at and for
You may find a combination solution (changing oil and change interval), maybe a mechanical fix, maybe it is a result of an inherent design- you just don’t know.

I recommend going that extra step because if you don’t you are addressing the symptom rather than the root cause so unless you accidently get lucky you can spend a lot of needless money and never really get satisfaction.

It’s cheaper in the long run.

Like I said in my original post, the 2.3L engine in the early Saab 9-5 had a tendency toward sludge formation. One of the reasons is that the catalytic converter is snuggled up next to the oil pan. Another reason is the PCV system, which was remedied about ten years ago by a Saab-recommended modification called PCV #6 Update.

I'm thinking about making my downpipe catless to prevent the oil pan from becoming a heat sink, and also for performance reasons.

 

[daves87rs]

Some short and sweet OCIk fine should work fine..

 

[Joel_MD]

What is HDEO? Heavy duty engine oil? High detergency?

I know some Saab guys use 5W-40 diesel oil like Rotella.

 

[Olas]

Heavy Duty

http://www.bobistheoilguy.com/forums/ubbthreads.php/forums/22/1/Heavy_Duty_Engine_Oil_(HDEO)_-

 

[4wheeldog]

Originally Posted By: Joel_MD
What is HDEO? Heavy duty engine oil? High detergency?

I know some Saab guys use 5W-40 diesel oil like Rotella.


That would be the animal.....Though it is available in 10W/30 varieties as well, which might be more appropriate. With short OCIs, Rotella T5, which is semisynthetic, would probably be adequate. And may be better, from the standpoint of not creating leaks. Good luck.

 

[Olas]

Red hot cat right next to the sump? That'll be your problem then!

Decat will fix it and help performance. Do have smog in your state? You might need to relocate it rather than delete it..

 

[Joel_MD]

Originally Posted By: Olas
Red hot cat right next to the sump? That'll be your problem then!

Decat will fix it and help performance. Do have smog in your state? You might need to relocate it rather than delete it..

There is a smog inspection in Maryland, but the test is not very sophisticated. On a vehicle equipped with OBDII all they do is look to see if there is a check engine light. They are supposed to do a visual inspection for emissions equipment as well, but in practice I believe it is rarely done. Some of the recommendations from my Maryland car buddies are to use a "fugazi" cat, or bash out the cat innards with a piece of rebar and a hammer. Or use the heat shield from a cat over the bare pipe so it looks like a cat. Also, some of the Saab tuners modify the ECU software so it ignores the downstream O2 sensor, so no CEL due to the missing/ineffective cat.

 

[Olas]

It's a win/win, do it!

Still do a couple of 200ish mile OCIs though, to get all the crud out and avoid blocking a galley and starving a bearing.

 

[zzyzzx]

Originally Posted By: Joel_MD
They are supposed to do a visual inspection for emissions equipment as well, but in practice I believe it is rarely done.


I just had my inspection done at the SW Baltimore City location maybe 2 weeks ago. tailpipe test on a 1995 car. Passed easily and they did not check for a cat.

With respect to your sludge, do some reading on Toyotanation, since they are experts on sludge over there. And cut open the filter and post pics of it here after your next oil change!

 

[HerrStig]

Originally Posted By: Joel_MD
Originally Posted By: Olas
Red hot cat right next to the sump? That'll be your problem then!

Decat will fix it and help performance. Do have smog in your state? You might need to relocate it rather than delete it..

There is a smog inspection in Maryland, but the test is not very sophisticated. On a vehicle equipped with OBDII all they do is look to see if there is a check engine light. They are supposed to do a visual inspection for emissions equipment as well, but in practice I believe it is rarely done. Some of the recommendations from my Maryland car buddies are to use a "fugazi" cat, or bash out the cat innards with a piece of rebar and a hammer. Or use the heat shield from a cat over the bare pipe so it looks like a cat. Also, some of the Saab tuners modify the ECU software so it ignores the downstream O2 sensor, so no CEL due to the missing/ineffective cat.
Some right fine Generous Motors engineering there.

 

[tezzzas]

I would go to wallymart, get some cheap supertech syn and peraluator oil filter, cheapest stuff you can get. You can get three oil changes for like 50 bucks. Use them for short OCI, cut the cans, and see how the sludge goes.

 

[Donald]

Replace the thermostat. More frequent oil changes using a quality HDEO oil.

 

[Stewie]

Run some T6