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This car has 79,000 original miles. The previous owner had the pan off and installed a brand new oil pump, but didn't clean the screen? If he had, then he left junk in the bottom of the pan when he reassembled. The pickup tube screen was loaded with bits of carbon and almost completely blocked. Anyway, I of course cleaned the tube and I would like to know if there are any modifications I can make (Besides changing the oil, I know that one :) before it goes back together to avoid this ever happening again. Is there an upgraded tube? Should I enlarge the screen holes? I'm waiting on a new gasket so I have a few days to make changes. Thanks in advance! IMG_20180311_180422.jpg IMG_20180311_182655.jpg
 

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To prevent this from happening again use full synth 0W40 Mobil 1 and change oil/filter every 5K miles.
 

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As Emry said. If you drive uphill often (or like to drive it hard), change the oil every 3k to be safe. Also make sure your PCV system is functioning properly.
 

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As Emry said. If you drive uphill often (or like to drive it hard), change the oil every 3k to be safe. Also make sure your PCV system is functioning properly.
Short trips (5 miles or less) could be a contributing factor. Servicing the PCV system on a regular basis is a must. Consider using a Big Kahuna size oil filter to increase the oil capacity by about a quart.
 

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In order of importance:
1. Proper cool down after hard driving
2. Oil spec (VW 502.00 full synthetic 0w40 or 5w40)
3. Oil change interval (5k miles)
4. PCV maintenance

167k miles sludge free. I am not even jinxing it. PCV was redone at 150k and wasn't even that caked up. The secondary hose they added from the bleeder to the valve cover starting in 03 lessened the issues with buildup in the PCV.
5k mile oil changes with 0w40 or 5w40 full synthetic 502.00 approved oil
I drive hard, but I let it idle or drive with no boost for the last couple of minutes.
VW recommended larger Mann 940/25 filter.
 
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Short trips (5 miles or less) could be a contributing factor.
You lost me on that. Sludge is built usually by long change intervals or using regular oil instead of full synth (due to high temp resistance). What has short trips to do with sludge build up?
 

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You lost me on that. Sludge is built usually by long change intervals or using regular oil instead of full synth (due to high temp resistance). What has short trips to do with sludge build up?
A natural by-product of combustion is water vapor. Blow-by gasses enter the crankcase, which is why there is a PCV system to remove them. It takes about 20 minutes of driving to raise the oil temperature high enough to boil off the moisture from the blow-by gases. Hence short trips will add moisture to the oil and moisture + oil = sludge.

If you don't figure out what is causing the coking / sludging of the oil the problem will just return. A vacuum / boost leak tester may be helpful - :: a4mods.com :: - The Premiere Audi A4 Modification Guide and Pictures Library - to be sure your PCV system is working as intended.
 

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A natural by-product of combustion is water vapor. Blow-by gasses enter the crankcase, which is why there is a PCV system to remove them. It takes about 20 minutes of driving to raise the oil temperature high enough to boil off the moisture from the blow-by gases. Hence short trips will add moisture to the oil and moisture + oil = sludge.

If you don't figure out what is causing the coking / sludging of the oil the problem will just return. A vacuum / boost leak tester may be helpful - :: a4mods.com :: - The Premiere Audi A4 Modification Guide and Pictures Library - to be sure your PCV system is working as intended.
I would say short trips is more harmful to the tranny than causing sludge. The turbo gets hot enough fast to evaporate any moisture in the oil. Besides, the full synth oil is less prone to absorb moisture compared to regular mineral oils. I think sludge is caused more by burning and getting rock hard in high turbo or engine temps than mixing some moisture in it. My 1.8T has 134K miles in it and I drive about 4 miles to work with it. It is totally sludge-free after 17 years of service. The VW sludge suite and recall was due to small capacity oil filter and not mentioning to customers to use full synth oil.
 

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Not every 1.8T Passat is going to have a sludge issue. The majority of them I see on the road are not owned by enthusiasts. I often wonder how they've been able to keep them on the road.

I used Mobil 1 (5W-30) from the first oil change on in my 2000, then upgraded to the 0W-40 spec oil when it was specified by VW. Oil change intervals were never even close to 5,000 miles yet I developed sludge. With a boost leak detector I was able to track down the numerous leaks I had. I test it from time to time to be sure no new ones have developed.

Maybe I'm being overly cautious but I try and balance out short trips with longer ones. Oil temp lags behind water temp. I continue to use synthetic oil which I change every 3,000 - 5,000 miles, along with a Big Kahuna size oil filter.
 

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Not every 1.8T Passat is going to have a sludge issue. The majority of them I see on the road are not owned by enthusiasts. I often wonder how they've been able to keep them on the road.
But what is there to be enthusiastic about? The most important thing should always be to have a reliable transportation from A to B and not sitting on the side of a highway waiting for a tow truck to arrive and then dealing with shops that try to rip you off with their outrageous labor cost.

I used Mobil 1 (5W-30) from the first oil change on in my 2000, then upgraded to the 0W-40 spec oil when it was specified by VW. Oil change intervals were never even close to 5,000 miles yet I developed sludge.
The problem was using 5W30. The 30 points to the high temperature tolerance of the oil. The higher the number the more heat the oil can handle. You used 30 instead of 40 and that caused the turbo to literally cook that oil and turn it to sludge.

Maybe I'm being overly cautious but I try and balance out short trips with longer ones. Oil temp lags behind water temp. I continue to use synthetic oil which I change every 3,000 - 5,000 miles, along with a Big Kahuna size oil filter.
That won't work because the damage done by short trips won't be undone or compensated by the longer one. It is true that it takes a while for the engine to reach its proper temperature and during that period there is all kind of mechanical stress imposed on the engine and other parts especially in cold climates.
 

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Two definitions of sludge are commonly used:
1. The gooey gunk that commonly builds up in the PCV system, caused by moisture and combustion byproducts.
2. The hard black specs that build up in parts of the engine where there is oil, caused by oil being burnt as it goes through the turbo.

There is no mod required in the bottom of the engine, the pickup pipe and screen are hard to clean, if you can't get them clean you should replace them.
If the timing belt and associated parts have not been replaced, they are now overdue for replacement.
 

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But what is there to be enthusiastic about? The most important thing should always be to have a reliable transportation from A to B and not sitting on the side of a highway waiting for a tow truck to arrive and then dealing with shops that try to rip you off with their outrageous labor cost.



The problem was using 5W30. The 30 points to the high temperature tolerance of the oil. The higher the number the more heat the oil can handle. You used 30 instead of 40 and that caused the turbo to literally cook that oil and turn it to sludge.



That won't work because the damage done by short trips won't be undone or compensated by the longer one. It is true that it takes a while for the engine to reach its proper temperature and during that period there is all kind of mechanical stress imposed on the engine and other parts especially in cold climates.
Ok, before you post any more incorrect information, please take a few days to read about oil over at https://www.bobistheoilguy.com/

Simply put, the number at the end is the viscosity at 100*C. That's it.

excerpt taken from Oil Specifications Explained - What does 10w40 mean?

VISCOSITY
Most oils on the shelves today are "Multigrades", which simply means that the oil falls into 2 viscosity grades (i.e. 10w-40 etc)
Multigrades were first developed some 50 years ago to avoid the old routine of using a thinner oil in winter and a thicker oil in summer.
In a 10w-40 for example the 10w bit (W = winter, not weight or watt or anything else for that matter) simply means that the oil must have a certain maximum viscosity/flow at low temperature. The lower the "W" number the better the oil's cold temperature/cold start performance.
The 40 in a 10w-40 simply means that the oil must fall within certain viscosity limits at 100°C. This is a fixed limit and all oils that end in 40 must achieve these limits. Once again the lower the number, the thinner the oil: a 30 oil is thinner than a 40 oil at 100°C etc. Your handbook will specify whether a 30, 40 or 50 etc is required.
 
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Two definitions of sludge are commonly used:
1. The gooey gunk that commonly builds up in the PCV system, caused by moisture and combustion byproducts.
2. The hard black specs that build up in parts of the engine where there is oil, caused by oil being burnt as it goes through the turbo.

There is no mod required in the bottom of the engine, the pickup pipe and screen are hard to clean, if you can't get them clean you should replace them.
If the timing belt and associated parts have not been replaced, they are now overdue for replacement.
Quoting for truth!

#2 is also known as oil coking. To elaborate on the cooldowns...If you shut the engine off after a hard run without idling or cooling for a few minutes, the oil will sit in the hot turbo and cook to a crisp.
 
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But what is there to be enthusiastic about?
You're missing his point. A enthusiast will know the proper spec oil for the car, use it and do timely oil changes. A non-enthusiast will go to Jiffy lube and ask for the $19.99 special (dino oil). Then eventually when the car breaks down or has an issue the first thing they will say is: "Damn VW, will never buy one again. With my (insert boring car here) all I had to do was put gas in it." :p

Rocket9K, I would recommend this:

For PCV pipes, I would go with these for starters : https://store.034motorsport.com/brea...-silicone.html You will need more than that.

For cleaning the hard pipes, you can use MAF cleaner or electrical contact cleaner and fish tank brushes (look like big pipe cleaners).
 

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Ok, before you post any more incorrect information, please take a few days to read about oil over at https://www.bobistheoilguy.com/

Simply put, the number at the end is the viscosity at 100*C. That's it.

excerpt taken from Oil Specifications Explained - What does 10w40 mean?

VISCOSITY
Most oils on the shelves today are "Multigrades", which simply means that the oil falls into 2 viscosity grades (i.e. 10w-40 etc)
Multigrades were first developed some 50 years ago to avoid the old routine of using a thinner oil in winter and a thicker oil in summer.
In a 10w-40 for example the 10w bit (W = winter, not weight or watt or anything else for that matter) simply means that the oil must have a certain maximum viscosity/flow at low temperature. The lower the "W" number the better the oil's cold temperature/cold start performance.
The 40 in a 10w-40 simply means that the oil must fall within certain viscosity limits at 100°C. This is a fixed limit and all oils that end in 40 must achieve these limits. Once again the lower the number, the thinner the oil: a 30 oil is thinner than a 40 oil at 100°C etc. Your handbook will specify whether a 30, 40 or 50 etc is required.
Alrite, first of all I had read that oil site and exactly what I said was based on the characteristics of oil at high temperature. So which part of my info was incorrect?

The higher number (i.e., 40) means the oil resists high temperatures better than 30. An oil with W30 grade won't hold its characteristics (being viscosity or any other) at higher engine temperature like a W40. Ain't that what I said?
 

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If you shut the engine off after a hard run without idling or cooling for a few minutes, the oil will sit int he hot turbo and cook to a crisp.
If you use full synth 0W40 oil, I don't think cooling down period is necessary. But if you are using any other non-approved oil then I'm not even sure cooling down idle would help much.
 

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I am not sure why you continue to fight without just researching and verifying.

It's not about which oil turns to sludge first. A 30 oil is not less resistant to heat than a 40 oil of identical formulation. It is strictly viscosity; the fluid's internal resistance to flow. The viscosity affects the film thickness as well. Too thin and it can't lubricate as well.

https://www.bobistheoilguy.com/putting-the-simple-back-into-viscosity/


You can do whatever you want with your engine. It is also up to the OP to determine the best course of action based on replies and widely available information.

If you get into full boost (even stock levels) and floor it, exhaust temps can easily reach 1200* at the turbo. Allowing the cooler exhaust temp from idling or driving lightly will help to pull out that extra heat that it absorbed so it will not radiate that heat into the oil left in the turbo after shut down.
 
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