Oil Change on GT4RS
#16
Can confirm that only half the oil is drained and replaced. I did a post break-in oil change at Manthey Racing just before taking my 4 RS on the 'Ring this past October. I think Manthey is pretty much as authoritative a source as you can get, short of AP himself
Potential reasons (some mentioned by the Manthey tech) for this new regimen include, 1) reduced chance of momentary oil starvation event and associated wear, because it takes oil pressure a fraction of a sec longer to build when the engine is cranked over right after a full oil change, 2) reduced oil cost, 3) improved oil formulations make oil last longer, especially with ~4 L of freshly added oil to dilute out effects of old oil.
Next time I'm in Weissach I'll be sure to ask!
Potential reasons (some mentioned by the Manthey tech) for this new regimen include, 1) reduced chance of momentary oil starvation event and associated wear, because it takes oil pressure a fraction of a sec longer to build when the engine is cranked over right after a full oil change, 2) reduced oil cost, 3) improved oil formulations make oil last longer, especially with ~4 L of freshly added oil to dilute out effects of old oil.
Next time I'm in Weissach I'll be sure to ask!
2) reduce oil cost…at 12$ per liter = 48 $ more per oil change for a gt4 rs owner, that’s peanuts
3) same oil as in my gt4 around 7.5 liters total
1) reduced chance of momentary oil starvation event and associated wear, Ok could be, but at the price of driving around with oil that is at best a mix of 50 -50 old new.
Some guys on this forum let their porsche drain overnight to try to get the most old oil out of the engine. and now it’s ok to drain only half the oil?
I can’t see the logic here. But I’m not an engineer either but still doesn’t make sense to drive around and do track days with half dirty oil (at best)
#17
Yes, the specified 4.1L drains when you remove the drain plug for the external oil tank, the engine sump drain plug, and the spin-on oil filter being removed.
While you can drain more oil (up to 7L), depending on draining duration and oil temperature, this is not part of the intended procedure. It is an unintended consequence and in my opinion, not desirable. They added this language after the fact to prevent someone from draining 7L (after being surprised that this is possible) and only adding 4.1L of new oil.
The engine is designed to retain a certain amount of oil in the heads and near the suction pump to allow for optimum oiling after an oil change.
There may be some other rationale at work here (less waste oil at time of change?), but I just change half the oil as specified but I change my oil very frequently so it’s always clean and retaining its specified viscosity.
While you can drain more oil (up to 7L), depending on draining duration and oil temperature, this is not part of the intended procedure. It is an unintended consequence and in my opinion, not desirable. They added this language after the fact to prevent someone from draining 7L (after being surprised that this is possible) and only adding 4.1L of new oil.
The engine is designed to retain a certain amount of oil in the heads and near the suction pump to allow for optimum oiling after an oil change.
There may be some other rationale at work here (less waste oil at time of change?), but I just change half the oil as specified but I change my oil very frequently so it’s always clean and retaining its specified viscosity.
Last edited by GrantG; 01-17-2023 at 01:33 AM.
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008 (01-17-2023)
#18
The service manual states the procedure to be "add 3.5 ltrs of oil, then measure". It should show 1 bar illuminated. Then add 1/2 ltr. which should bring it up to 3 bars. The manual states that for cars that go on a race track, do not exceed 3 bars. A comment about oil level - during a Manthey Porsche track day, the techs set the oil level on Porsche owned cars even less - to 1 bar or below.
Last edited by matttheboatman; 01-17-2023 at 10:22 AM.
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HooosierDaddy (08-01-2023)
#20
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GrandPaJohn (01-17-2023)
#21
Service manager let me take a couple pics off his computer
was there checking out our Macan GTS that was just unloaded when got to talking about oil service on the RS. He didn’t think it sounded right so we went and looked it up. Needless to say he was shocked.
Last edited by HooosierDaddy; 01-18-2023 at 12:25 PM.
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DFW01TT (01-18-2023)
#25
#26
Checking with Suncoast parts now to see if they sent me the wrong plug.
This simple DIY has turned more complex, particularly after reading about the issue discovered on the GT3s 4.0 ltr engines (same as GT4RS) of the brass insert in the carbon fiber sump oil tank being stripped while loosening when the engine is hot. Good grief! I just want to change my oil, how difficult can that be? Apparently, more difficult than I could have imagined. So here I am in the process...
1. Need to confirm the correct plug was sent to me. And, if as I suspect it is the wrong part, get the proper sealing plug and associated new tool. Then,
2. Need to bring the car to the Porsche dealer, let it sit overnight so it cools to ambient temperature as prescribed for loosening the oil tank drain plug.
3. Have them put the car on the lift, have the P-tech loosen the oil tank plug so if it strips, its on them, not on me, then proceed.
More to follow ....
This simple DIY has turned more complex, particularly after reading about the issue discovered on the GT3s 4.0 ltr engines (same as GT4RS) of the brass insert in the carbon fiber sump oil tank being stripped while loosening when the engine is hot. Good grief! I just want to change my oil, how difficult can that be? Apparently, more difficult than I could have imagined. So here I am in the process...
1. Need to confirm the correct plug was sent to me. And, if as I suspect it is the wrong part, get the proper sealing plug and associated new tool. Then,
2. Need to bring the car to the Porsche dealer, let it sit overnight so it cools to ambient temperature as prescribed for loosening the oil tank drain plug.
3. Have them put the car on the lift, have the P-tech loosen the oil tank plug so if it strips, its on them, not on me, then proceed.
More to follow ....
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008 (01-24-2023)
#28
My car isn't here yet, andI will likely have the dealer do at least the first few oil changes anyway, mostly just to help inspect for any other issues, but definitely do most of my cars services myself.
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OK, did some searching, found a few threads and the TSB. Reposting the TSB here for others that might have missed it in the 992 GT3 forum.
Sounds like this issue might have been limited to early production engines only, before Jan 27, 2022. Any reason to suspect that a recent build 4RS might have this issue?
Last edited by pfbz; 01-24-2023 at 12:20 AM.
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pfbz (01-24-2023)
#30