Preventing depoits-How?

[Dually]

If you change your oil every 3K-5K and use a quality conventional or synthetic oil can you still over time accumulate depoits like varnish/sludge?What condition(internal) are the engines(gas)that use only conventional oil for 5K OCI and the engine was dismantled at 150,000 miles?Thanks Joe

 

[Lonnie]

I think the more important issue is not the exact oil, but the driving conditions and driving habits of the vehicle operator. Take any modern car and use the factory recommended oil, drive in good weather and do reasonalbe maintenance, have good driving habits and if you have sludge, something else is wrong. I don't know what you can do about those shiny varnish deposits and I have no idea if they have anything to do with the life of the engine, and I'm not talking about extreme amounts of varnish. I help manage data and testing for a large fleet operation and time and again, the thing that beats an engine is weather, driving conditions and an operator that does on exercise care in the operation of the vehicle. Any API cert oil is good enough under normal conditions. We tore down a 200k Ford Crown Vic in police duty, that used Motorcraft 5w-30. The engine would have never been touched, except the car was totaled in an accident. The engine showed no signes of sludge and 'miked' out at new car specs for many internal measurements. If you have sludge, something else is going on.

 

[andyd]

any 1/2 way decent engine should run considerably longer than 150k miles with just about any modern oil observing a 5k OCI as long as the oil is the recommended viscosity. Clean is relative. Out of curiosity, I pulled the valve cover off my 528e at 330k. It wasnt spotless, I removed maybe a 1/2 cup of sludge from the top of the head and the inside of the VC and it was varnished. Big honkin deal. Ive been running cheap Mobil or Supertec oil in the 10 yrs I've owned it. I observe a 3-4k OCI and prolly could stretch that to 5k

 

[BrianWC]

The big honkin' deal is when/if those deposits clog the oil screen pickup and starve the bearings of oil, spinning a bearing and slinging a rod.

 

[427Z06]

Quote:

---

We tore down a 200k Ford Crown Vic in police duty, that used Motorcraft 5w-30. The engine would have never been touched, except the car was totaled in an accident. The engine showed no signes of sludge and 'miked' out at new car specs for many internal measurements. If you have sludge, something else is going on.

---

There was another Ford Crown Vic in police duty with 200K on MC 5w20, or we talking about the same vehicle?

 

[JohnBrowning]

You know we are really entering a new era in reguards to dino oil. SM/GF4 is so much better then what was ont he market when I was a young man and working as a Tech. that it is almost a guess. I see deposit control getting better and better with dino but I worry about long term wear. They keep decreaseing Phos., sulfur and zink and the additives they are trying to use to replaces them are not doing as good of a job probably could be solved with higher levels of them. I am sure that 3K-5K is not much of a problem but a lot of vechiles are going much longer then this in general. In some cases it is because of neglect inother cases it is because of on board OLM. While the base stocks are greatly improveing in terms of deposit control I really have my doubts about 7000+++ OCI's with the low levels of traditional additives.Just my $.02 though.

 

[Rand]

I agree mostly but another factor is what car are you putting it in.
If its a modern econobox thats a different story than a 1979
land yacht.
Roller valvetrain better mpg etc.

 

[The Critic]

A light to moderate coat of varnish is expected. No one expects those engines to stay spotless...I mean, I'm sure it's possible with the right oil and conditions, but what's there to gain??

 

[427Z06]

There are now two Crown Vic Police Duty vehicles using MC 5w20 that have gone 200K miles. One was dismantled because it was totaled, and showed very little wear.

http://theoildrop.server101.com/forums/s...3141#Post753141
http://theoildrop.server101.com/forums/s...5552#Post765552

Not only have oils become better with each successive API service spec. Some new oils also include advanced additives that aren't normally noticeable in a $20 UOA.

In the same light, engines have changed over the years. Computer controlled MPFI and spark timing, distributorless ignition systems, improved manufacturing techniques to include surface finishes, improved metallurgy, specialized surface coatings, rollerized valvetrains (many OHC), crank driven g-rotor oil pumps, etc, etc.

Unless one is trying to extend their OCIs past manufacturer's recommendations, worrying about additive levels is a waste of time. Simply perform a UOA and have it professionally interpreted if long drains are your goal.

 

[buster]

Quote:

---

Not only have oils become better with each successive API service spec

---

Yep. Many knock the API, but I see them as a good organization.

 

[Ugly3]

The big honkin' deal is when/if those deposits clog the oil screen pickup and starve the bearings of oil, spinning a bearing and slinging a rod.

Have you seen an engine with a clogged pick up screen? I have and it was not a case of a few varnish spots or a little scum in the engine. It was always a ginormus mess caused by a lack of any normal level of maintenance.

 

[The Critic]

Quote:

---

Have you seen an engine with a clogged pick up screen? I have and it was not a case of a few varnish spots or a little scum in the engine. It was always a ginormus mess caused by a lack of any normal level of maintenance.

---

Lack of normal maintenance is the right term. If the oil was changed per the OLM or OEM service interval, which is generally every 5-7k miles/6-8 months, it's very, very unlikely that such will occur, unless there was a coolant leak or another major mechanical problem.

 

[BrianWC]

Quote:

---

The big honkin' deal is when/if those deposits clog the oil screen pickup and starve the bearings of oil, spinning a bearing and slinging a rod.

Have you seen an engine with a clogged pick up screen? I have and it was not a case of a few varnish spots or a little scum in the engine. It was always a ginormus mess caused by a lack of any normal level of maintenance.

---

Well that confirms no one has ever read a single post I've made.

Yes, I have seen PLENTY of engines with clogged pickups, including my own. It is VERY IMPORTANT to pick the right oil in a 9-5 b/c they have very fine mesh over the pickup. SAAB's with the b235 engine are very prone to this b/c of a pcv system not prepared to handle the increased blowby of the engine. Some of them have been sludged and oil starved in as little as 20,000 miles.

So yes, I've seen my share and no, it does not take a complete lack of maintenance.

 

[Drew99GT]

This post confirms I guess no one has read my posts as well; the ones where my father's 200,000 mile 4300 Blazer was spotless inside when the intake was off for lower gasket replacement. My moms 150,000 mile Olds 88 with the 3800 is spotless inside as well. Oil has mostly been Pennzoil 5w-30 until I took over maintenance duties an now it gets whatever's cheapest in name brand dino.

Now, that doesn't mean the ring packs and combustion chambers are clean. That's why they've been auto-rxed and seafoamed!

Oil change intervals were 3,000 on the dot with Pennzoil, but I'm a hint more lax about it. Instead of writing down an exact mileage of when to change, I write down when it was changed and then judge the next change by the driving conditions the vehicle was subject to. If it's been 4 months or so and about 2500-3,000 miles short trips, I'll change it. On the other hand, I've gone out to about 5500 when the vehicles were subject to road trips. That's as far as I'll go!

 

[BrianWC]

Of course. It depends on the car, driving habits, etc. My Honda gets whatever I grab outta the stash.

 

[Lonnie]

It's odd that Saabs are sludge monsters. Don't they come from a place that is really cold? You'd think that they would handle hash conditions, including resisting getting sludged up. So, I asked someone, today, that has an older Saab with a turbo if he had any problems. He said no, and he changes the oil every 5k miles. He uses Red Line. He does have a problem. The turbo is mounted right next to the battery, and even with a heat shield, the battery gets cooked. He as fabricated a bigger heat shield, but the batteries still get cooked. It looks like the turbo setup was not well thought out. This owner is actually buying all the goodies to move the battery to the trunk. This mod might qualify him as a senior Saab engineer. The turbo installation looks like a high school auto shop project that had to be finished before the bell. At least he does not have any sludge, and maybe Red Line and 5k oci's helped.

 

[BrianWC]

It's not all saabs. It's the 99-02 b235 engines that are the big sludgers. A faulty pcv design after an engine redesign was the big issue. This caused a cascade efect, highlighting every weakness in the engine. These weaknesses included extra fine pickup screen mesh That was clogging with a combo of carbon deposits and decayed hose rubber. PCV update #6 finally seems to solve the problem

 

[Gary Allan]

Quote:

---

Unless one is trying to extend their OCIs past manufacturer's recommendations, worrying about additive levels is a waste of time. Simply perform a UOA and have it professionally interpreted if long drains are your goal.

---

Yes, assuming no design flaws ..the only time you should run into issues is if you mismatch the OCI with the service. Factory recommendation surely have a fudge factor included in them (again, assuming a sound design). The rest should be a wash and fall into background noise level type stuff.

When OLM is a standard item ..then the service will always be factored into the equation. Right now it's all somewhat subjective and speculative. You can then, with UOA, gauge your own personal 'standard deviation' based on your personal oil selection (your own fudge factor).

 

[427Z06]

Quote:

---

Quote:

---

Unless one is trying to extend their OCIs past manufacturer's recommendations, worrying about additive levels is a waste of time. Simply perform a UOA and have it professionally interpreted if long drains are your goal.

---

Yes, assuming no design flaws...

---

Yes, I forgot to put the standard disclaimer in there, "...unless you have a sludge monster, defective components, design flaws or a flat tappet pushrod pig iron engine with hipo valvetrain components."

 

[BrianWC]

put me down for design flaws..........