I've got a Beetle with a turbo. Is that thing doing nasty destruction to my oil? Maybe I should cut intervals in half (to 5000).
Do turbos damage oil?
- Thread starter rrrrrroger
- Start date
- Status
Do a UOA and find out. But generally yes, a hard working turbo can be tougher on oil. Is yours hard working (ie. using high boost levels)? If it's stock, it probably isn't.
Originally Posted By: rrrrrroger
I've got a Beetle with a turbo. Is that thing doing nasty destruction to my oil? Maybe I should cut intervals in half (to 5000).
Some Porsch turbos are real hot runners and do shear the oil, but not a normal car one. The VW recommended service interval will be good, but make sure you use the correct oil grade and type with a real VW filter.
Time at idle or short trips kill engine oil far more, so if you spend a lot of time in traffic cut the OCI in half, but don't change the filter until the recommended interval, just do alternate oil only changes.
I've got a Beetle with a turbo. Is that thing doing nasty destruction to my oil? Maybe I should cut intervals in half (to 5000).
Some Porsch turbos are real hot runners and do shear the oil, but not a normal car one. The VW recommended service interval will be good, but make sure you use the correct oil grade and type with a real VW filter.
Time at idle or short trips kill engine oil far more, so if you spend a lot of time in traffic cut the OCI in half, but don't change the filter until the recommended interval, just do alternate oil only changes.
The oil for that engine is VW Spec 502 and the only oils that meet that spec are synthetic - not synth blend .
Use a top notch synthetic to avoid pesky deposits. Not all oils are created equal at preventing them, although the gap has closed significantly over the last few years. Take a look at what Honda found back in 2006 in regards to turbo and deposit control.
I think it depends on the turbo-the one on the '82 300D (non-intercooled turbo diesel) still spools up and bearings appear to be fine, original with over 200K on it-not sure what VW uses.
Like they said, use the best and most appropriate oil that you can.
And yes, Turbos are hard on oil for 2 reasons: more power and resultant heat in the sump, and extreme heat in the actual turbo where the oil lubes it - way extreme.
And yes, Turbos are hard on oil for 2 reasons: more power and resultant heat in the sump, and extreme heat in the actual turbo where the oil lubes it - way extreme.
To expand on what mechtech2 said.
The extreme heat from turbos accelerates oil oxidation, and the stresses from the fluid bearings(hydrdynamic, or hydrostatic in this case) cause shearing. Turbos are one of the reasons that hdeo oils need to be so shear resistant compared to pcmo..
The extreme heat from turbos accelerates oil oxidation, and the stresses from the fluid bearings(hydrdynamic, or hydrostatic in this case) cause shearing. Turbos are one of the reasons that hdeo oils need to be so shear resistant compared to pcmo..
Simple answer, yes. Make sure you use an oil that meets VW specs 502.00. Oil will be synthetic.
I would not cut/reduce my OCI do to car being equipped with a turbo. Dont worry about the turbo. The obvious being that using a cheap oil can and will cause problems.
Originally Posted By: OB4x4
To expand on what mechtech2 said.
The extreme heat from turbos accelerates oil oxidation, and the stresses from the fluid bearings(hydrdynamic, or hydrostatic in this case) cause shearing. Turbos are one of the reasons that hdeo oils need to be so shear resistant compared to pcmo..
Not disputing your statement buy why would a PCMO not need to be as share stable. They are usually described as suitable for turbos. Some petrol turbo engines are designed to be worked hard too, e.g. Porsche.
To expand on what mechtech2 said.
The extreme heat from turbos accelerates oil oxidation, and the stresses from the fluid bearings(hydrdynamic, or hydrostatic in this case) cause shearing. Turbos are one of the reasons that hdeo oils need to be so shear resistant compared to pcmo..
Not disputing your statement buy why would a PCMO not need to be as share stable. They are usually described as suitable for turbos. Some petrol turbo engines are designed to be worked hard too, e.g. Porsche.
Originally Posted By: Quattro Pete
Do a UOA and find out. But generally yes, a hard working turbo can be tougher on oil. Is yours hard working (ie. using high boost levels)? If it's stock, it probably isn't.
They do shear oil if you push the car hard, but I don't see how you can do that in the USA at 65 mph too easily. The BMW 5 forum averaged UOA results showed little difference between good quality part synthetic and full G4 Synthoils at 5K mile OCI's. The big difference is in the extended OCI intervals, but if in doubt always use at least an HC synthetic oil and check the major brand oil guides or VW approvals, rather than guess.
What I find bad about oil advice is the tendency for dealers in the US not to offer several different oils, but push the cheapest one only. That results in many US VW TDI's using part dino or dinoblend when they should be informed about the VW full synthetic recommendation and a longer OCI option.
Do a UOA and find out. But generally yes, a hard working turbo can be tougher on oil. Is yours hard working (ie. using high boost levels)? If it's stock, it probably isn't.
They do shear oil if you push the car hard, but I don't see how you can do that in the USA at 65 mph too easily. The BMW 5 forum averaged UOA results showed little difference between good quality part synthetic and full G4 Synthoils at 5K mile OCI's. The big difference is in the extended OCI intervals, but if in doubt always use at least an HC synthetic oil and check the major brand oil guides or VW approvals, rather than guess.
What I find bad about oil advice is the tendency for dealers in the US not to offer several different oils, but push the cheapest one only. That results in many US VW TDI's using part dino or dinoblend when they should be informed about the VW full synthetic recommendation and a longer OCI option.
Back in the day, a neighbour had an early (80s) aftermarket turbo on a 240 Volvo...18psi boost, with all of the gapless, forged, tricky bits...pre water cooled bearings.
Bloke who installed the aftermarket stuff argued that regular GTX was all that was needed, and that idle down was a fad.
Neighbour chewed up a number of centre sections (actually, whole turbos at that stage of the market in Oz, and finally decided on Agip sint 2000 10W-50, idle down to the point that he and his family had their seatbelts off, lights off etc....then used the 5,000km old oil a second time in his Datsun 1000/1200s beaters...way cheaper than new turbos.
A few points:
* aftermarket, non water cooled;
* aftermarket, high boost;
* mineral oil, no idle down.
That were solved by synthetic oil and idle down.
A petrol engine runs at stoichiometric, or pretty close, so has a pretty constant exhaust temperature, and during the idle down period, the exhaust system can get rid of the heat that has accumulated during use.
When you shut off the engine, the oil flow through turbo bearings stops, and what oil that remains has to cope with the heat that's left...hotter metal, hotter oil, more coke. (Water cooled helps a lot with this)...pulling off a highway into a petrol station is bad news on a petrol turbo.
Wouldn't worry about genuine shearing too much, as the bearings are hydrodynamic, and the radial loads on a turbo are comparatively light.
Diesel turbos are a different kettle of fish, as running lean of stoichiometric, the exhaust gasses are cooler...pulling off the highway into a petrol station not nearly so bad, certainly not ideal, but not as bad as petrol turbo.
Maybe that's why HDMOs are "apparently" so shear stable...they can be wrecked in a motorcycle transmission in short order, for all of their "stability".
Bloke who installed the aftermarket stuff argued that regular GTX was all that was needed, and that idle down was a fad.
Neighbour chewed up a number of centre sections (actually, whole turbos at that stage of the market in Oz, and finally decided on Agip sint 2000 10W-50, idle down to the point that he and his family had their seatbelts off, lights off etc....then used the 5,000km old oil a second time in his Datsun 1000/1200s beaters...way cheaper than new turbos.
A few points:
* aftermarket, non water cooled;
* aftermarket, high boost;
* mineral oil, no idle down.
That were solved by synthetic oil and idle down.
A petrol engine runs at stoichiometric, or pretty close, so has a pretty constant exhaust temperature, and during the idle down period, the exhaust system can get rid of the heat that has accumulated during use.
When you shut off the engine, the oil flow through turbo bearings stops, and what oil that remains has to cope with the heat that's left...hotter metal, hotter oil, more coke. (Water cooled helps a lot with this)...pulling off a highway into a petrol station is bad news on a petrol turbo.
Wouldn't worry about genuine shearing too much, as the bearings are hydrodynamic, and the radial loads on a turbo are comparatively light.
Diesel turbos are a different kettle of fish, as running lean of stoichiometric, the exhaust gasses are cooler...pulling off the highway into a petrol station not nearly so bad, certainly not ideal, but not as bad as petrol turbo.
Maybe that's why HDMOs are "apparently" so shear stable...they can be wrecked in a motorcycle transmission in short order, for all of their "stability".
Originally Posted By: Shannow
...pulling off a highway into a petrol station is bad news on a petrol turbo
I knew there was a reason to leave it running during fill-ups! It cools the turbo!
...pulling off a highway into a petrol station is bad news on a petrol turbo
I knew there was a reason to leave it running during fill-ups! It cools the turbo!
Originally Posted By: GearheadTool
Originally Posted By: Shannow
...pulling off a highway into a petrol station is bad news on a petrol turbo
I knew there was a reason to leave it running during fill-ups! It cools the turbo!
No you didn't!
And you shouldn’t be idling during fill ups. Most gas stations, at least up here, will not turn on the pump if they notice the car idling.
People that leave their car idling during fill up do it out of their laziness and ignorance for their own and others safety.
Originally Posted By: Shannow
...pulling off a highway into a petrol station is bad news on a petrol turbo
I knew there was a reason to leave it running during fill-ups! It cools the turbo!
No you didn't!
And you shouldn’t be idling during fill ups. Most gas stations, at least up here, will not turn on the pump if they notice the car idling.
People that leave their car idling during fill up do it out of their laziness and ignorance for their own and others safety.
Last edited:
Originally Posted By: Shannow
When you shut off the engine, the oil flow through turbo bearings stops, and what oil that remains has to cope with the heat that's left...hotter metal, hotter oil, more coke. (Water cooled helps a lot with this)...pulling off a highway into a petrol station is bad news on a petrol turbo.
That's why many modern turbo designs have after-run cooling pumps that continue on even after you shut the car off.
When you shut off the engine, the oil flow through turbo bearings stops, and what oil that remains has to cope with the heat that's left...hotter metal, hotter oil, more coke. (Water cooled helps a lot with this)...pulling off a highway into a petrol station is bad news on a petrol turbo.
That's why many modern turbo designs have after-run cooling pumps that continue on even after you shut the car off.
If it's still the stock turbo, it would be the KO3 version which runs @ about 9psi with small peaks of 10-11 psi. Not all that high of boost in the scheme of things. But it still will produce a good amount of heat in normal driving.
Is the OCI flexible or does the service light come on at set 10k mile intervals? If it is a set interval, it was recommended that the interval be reduced to 5k miles using a VW 502.00 rated oil. If it is a flexible OCI, I would still do 5k miles max with said 502.00 oil.
Now if you go stage 1 or more, or install a KO4 or an RS4 turbos, then I would suggest to go up and above 502.00 and stick with 5k miles. Probably a 5W-40 HDEO or RedLine 5W-30 or higher.
Is the OCI flexible or does the service light come on at set 10k mile intervals? If it is a set interval, it was recommended that the interval be reduced to 5k miles using a VW 502.00 rated oil. If it is a flexible OCI, I would still do 5k miles max with said 502.00 oil.
Now if you go stage 1 or more, or install a KO4 or an RS4 turbos, then I would suggest to go up and above 502.00 and stick with 5k miles. Probably a 5W-40 HDEO or RedLine 5W-30 or higher.
If I were you, I'd pose the question to a forum for other owners of the same type of vehicle that you have. Read the manual, but understand that what's in the manual may not be what is best for your car.
For example, I own a 2005 Subaru Forester XT. In my owner's manual it states that 5w30 is the recommended grade for best fuel economy, but it goes on to state that SAE 30, SAE 40, 20w40, and 20w50 are recommended for individuals living in high heat areas or high stress applications.
It turns out that the way most people drive a turbocharged Subaru is considered a high stress application, and that any oil lighter than a 10w40 can shear down to an unacceptably thin viscosity after extended high performance activity and ruin the motor. I only learned this after reading many posts on various Subaru forums that the OM recommendation is poorly worded, and lots of people running 5w30 experienced rapid oil loss, spun bearings, broken ringlands, etc.
Find some other turbo beetle owners and discuss with them. Turbos can really do a number on the oil, but a lot of that depends on how hard you drive the car. The recommended oil grade should be seen as a minimum.
For example, I own a 2005 Subaru Forester XT. In my owner's manual it states that 5w30 is the recommended grade for best fuel economy, but it goes on to state that SAE 30, SAE 40, 20w40, and 20w50 are recommended for individuals living in high heat areas or high stress applications.
It turns out that the way most people drive a turbocharged Subaru is considered a high stress application, and that any oil lighter than a 10w40 can shear down to an unacceptably thin viscosity after extended high performance activity and ruin the motor. I only learned this after reading many posts on various Subaru forums that the OM recommendation is poorly worded, and lots of people running 5w30 experienced rapid oil loss, spun bearings, broken ringlands, etc.
Find some other turbo beetle owners and discuss with them. Turbos can really do a number on the oil, but a lot of that depends on how hard you drive the car. The recommended oil grade should be seen as a minimum.
- Status
Similar threads
