The 03 Buick in my sig is the first S/C'd car I've owned and am on the fence with what oil to run. Is 10w30 absolutely required to keep the engine happy or can I just run 5w30 year round? Planning to stick with Pennzoil Conventional or Quaker State Conventional which I know is a quality oil. But, because it gets so stinking cold here in the winter, I'd feel a lot better about having 5W in there all the time. Car probably won't get used much in the winter since our city has some of the laziest snow removal guys in the world working for them and I don't like getting stuck everywhere, but, just in case it does occasionally get ran around. My job is seasonal for nice weather only so I don't do much or go places in the cold months.
10W-30 vs 5W-30 supercharged GM 3800 V6
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I'd run a good 5w40 in it and call it a day.
Wasnt this era GM cars notorious for HG failures? Or was that a few years earlier?
Wasnt this era GM cars notorious for HG failures? Or was that a few years earlier?
All those 3.8 back then had 10w30 on the cap. Being supercharged find the lowest noack/highest hths rating synthetic 10w for summer. Winter find a 5w like M1,Redline,Amsoil,etc
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Being supercharged find the lowest noack/highest hths rating synthetic
Wise words. In practical terms, that's Mobil 1 10w30 HM. HTHS 3.5. (keep in mind HTHS is a logarithmic scale, so don't think "oh, 3.2" is good enough"). If you aren't starting it routinely below 10F (e.g., you have a 2nd car for nasty weather), then run it year round, even in MT. Let me quote Molakule from a long time ago (over 15 years!):
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A jump in HTHS by about +1.5 results in approximately 1/5 the wear. Now this relationship is not linear and flattens as one nears a 40+ weight oil.
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We are not talking about a 1/10 difference between 3.2 and 3.5 like appears, but rather a 25 fold difference (1/5th of 1/5th). So I'm always going with a 3.5 HTHS where it meets my climate needs vs. a 5w30 with a 3.2 or lower HTHS. Heck, even mediocre 10w30's have an HTHS of 3.2. So look beyond the mere viscosity rating. Serious oil gurus here (like Shannow), have argued that oil marketed by viscosity is outmoded and it would be better to discard that and label it by HTHS.
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My job is seasonal for nice weather only so I don't do much or go places in the cold months.
So I don't exactly know what this means, but if you don't HAVE to start it when it has set outside overnight in 10F or lower, just run the 10w30 year round and there is no harm and only good.
* Here is the 2003 post I am quoting:
https://bobistheoilguy.com/forums/ubbthreads.php/topics/530501/1/HTHS
Being supercharged find the lowest noack/highest hths rating synthetic
Wise words. In practical terms, that's Mobil 1 10w30 HM. HTHS 3.5. (keep in mind HTHS is a logarithmic scale, so don't think "oh, 3.2" is good enough"). If you aren't starting it routinely below 10F (e.g., you have a 2nd car for nasty weather), then run it year round, even in MT. Let me quote Molakule from a long time ago (over 15 years!):
Quote
A jump in HTHS by about +1.5 results in approximately 1/5 the wear. Now this relationship is not linear and flattens as one nears a 40+ weight oil.
*
We are not talking about a 1/10 difference between 3.2 and 3.5 like appears, but rather a 25 fold difference (1/5th of 1/5th). So I'm always going with a 3.5 HTHS where it meets my climate needs vs. a 5w30 with a 3.2 or lower HTHS. Heck, even mediocre 10w30's have an HTHS of 3.2. So look beyond the mere viscosity rating. Serious oil gurus here (like Shannow), have argued that oil marketed by viscosity is outmoded and it would be better to discard that and label it by HTHS.
Quote
My job is seasonal for nice weather only so I don't do much or go places in the cold months.
So I don't exactly know what this means, but if you don't HAVE to start it when it has set outside overnight in 10F or lower, just run the 10w30 year round and there is no harm and only good.
* Here is the 2003 post I am quoting:
https://bobistheoilguy.com/forums/ubbthreads.php/topics/530501/1/HTHS
Originally Posted by GumbyJarvis
I'd run a good 5w40 in it and call it a day.
Wasnt this era GM cars notorious for HG failures? Or was that a few years earlier?
Disregard. That was the 2.8/3.1/3.4 family of engines.
Maxlife 10w40 has a HTHS of 3.9, Castrol GTX HM 10w40 has a min 3.5. As said above, if you're not going 10 F or lower, I as well would recommend a 10w-XX oil.
I'm not at all the type that thinks "the thicker the better" but with a high mileage supercharged engine, a Xw40 would be ideal, no?
I'd run a good 5w40 in it and call it a day.
Wasnt this era GM cars notorious for HG failures? Or was that a few years earlier?
Disregard. That was the 2.8/3.1/3.4 family of engines.
Maxlife 10w40 has a HTHS of 3.9, Castrol GTX HM 10w40 has a min 3.5. As said above, if you're not going 10 F or lower, I as well would recommend a 10w-XX oil.
I'm not at all the type that thinks "the thicker the better" but with a high mileage supercharged engine, a Xw40 would be ideal, no?
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I have a 2000 Regal (see Sig) LS 67 3800
Run Full Synthetic Quaker State Ultimate Durability 5w30 , car is stored for winter as it came from GA ,, no snow no salt,,
ALWAYS run oil samples to make sure your head gaskets are intact ,,,,
and your 3800 will be a happy camper
ZZ Performance Grand Rapids did some work for me and filled it with Mobil 1 5W30 ran it the rest of the summer before putting it away.
Be sure to change out your supercharger oil , people seem to forget that and it can lead to problems
I've put 50 K on this car since I acquired it
Run Full Synthetic Quaker State Ultimate Durability 5w30 , car is stored for winter as it came from GA ,, no snow no salt,,
ALWAYS run oil samples to make sure your head gaskets are intact ,,,,
and your 3800 will be a happy camper
ZZ Performance Grand Rapids did some work for me and filled it with Mobil 1 5W30 ran it the rest of the summer before putting it away.
Be sure to change out your supercharger oil , people seem to forget that and it can lead to problems
I've put 50 K on this car since I acquired it
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You can run a 5W30 year round; I do and have been for years (AND I do UOA) in your same engine (mine are nonsupercharged). Two things noteworthy to this discussion: 1) The supercharger uses a separate oil. https://zzperformance.com/collections/3800/products/gm-supercharger-oil and 2) The next model year, 2004, GM changed their oil spec for the SAME engine. My wife drives an 04 Buick with the 3.8 and the oil cap says "5W30." Finally, the OP may enjoy clicking around for awhile on this site: https://zzperformance.com/collections/3800 They have all kinds of goodies to mod your 3.8 or just make it run better. The internals on this little beast are so stout it is raced, turbo'd, and CAN make awesome HP with a stock crankshaft. I have 3 vehicles with this engine, my daily driver is an 03 (that I run 5W30 in). For the record regarding 5W30, here are pics of my wife's 04 engine compartment:
![[Linked Image]](https://www.bobistheoilguy.com/forums/attachments/usergals/2019/07/full-66646-34113-img_7756.jpg "[Linked Image]")
![[Linked Image]](https://www.bobistheoilguy.com/forums/attachments/usergals/2019/07/full-66646-34114-img_7757.jpg "[Linked Image]")
I had a few thunderbird supercoupes, they share the same eaton m90 blower as these GM cars.
I have never had a FWD GM 3800 sc car, but it would be something neat to tool around in.
I would say 10w30 motor oil, and change the blower oil out, it is fairly simple to do, and it stinks like ever.
The blower oil is more like jet turbine oil, purchase it from the GM dealer.
If the coolant has not been done I would have it vacuum changed immediately as well.
I have never had a FWD GM 3800 sc car, but it would be something neat to tool around in.
I would say 10w30 motor oil, and change the blower oil out, it is fairly simple to do, and it stinks like ever.
The blower oil is more like jet turbine oil, purchase it from the GM dealer.
If the coolant has not been done I would have it vacuum changed immediately as well.
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Use a good 10w30. Pennzoil conventional will be perfect.
I've owned several GM 3800 Series II cars. Do my own maintenance and repairs. Know them well.
When I owned a 1999 Buick Park Avenue Ultra with the supercharged 3800, it seemed to run best with Quaker State Ultimate Durability 5W30 year around.
The 3800 is a solid engine and will get along with any reputable oil as marked on the cap.
When I owned a 1999 Buick Park Avenue Ultra with the supercharged 3800, it seemed to run best with Quaker State Ultimate Durability 5W30 year around.
The 3800 is a solid engine and will get along with any reputable oil as marked on the cap.
Double post.
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I also use 5w30 SOPUS(PP/Quaker State Ultimate Durability) oil in mine for years with zero issues. This engine is not picky, but I would stick with a good synthetic in the 5w30 as recommended.
Originally Posted by benjy
oil blenders are "hiding" HTHS as well as Noack ratings these days, seems the newer oils the less specs they show SOPUS oils included!!
It should be require to be printed on the bottle.
oil blenders are "hiding" HTHS as well as Noack ratings these days, seems the newer oils the less specs they show SOPUS oils included!!
It should be require to be printed on the bottle.
Originally Posted by JustinH
I had a few thunderbird supercoupes, they share the same eaton m90 blower as these GM cars.
I have never had a FWD GM 3800 sc car, but it would be something neat to tool around in.
I would say 10w30 motor oil, and change the blower oil out, it is fairly simple to do, and it stinks like ever.
The blower oil is more like jet turbine oil, purchase it from the GM dealer.
If the coolant has not been done I would have it vacuum changed immediately as well.
Yeah I plan to change the S/C oil soon. Figure I'll use the spray bottle method to get it out and probably put vicks under my nose!
I had a few thunderbird supercoupes, they share the same eaton m90 blower as these GM cars.
I have never had a FWD GM 3800 sc car, but it would be something neat to tool around in.
I would say 10w30 motor oil, and change the blower oil out, it is fairly simple to do, and it stinks like ever.
The blower oil is more like jet turbine oil, purchase it from the GM dealer.
If the coolant has not been done I would have it vacuum changed immediately as well.
Yeah I plan to change the S/C oil soon. Figure I'll use the spray bottle method to get it out and probably put vicks under my nose!
You could run a higher HTHS Dexos2 rated oil in there, instead of a GF-5 or D1-G2 lower HTHS oil.
In Australia, Dexos2 is often used as the performance GM oil in petrol (gas) engines as well as the light duty diesel engine oil.
In Australia, Dexos2 is often used as the performance GM oil in petrol (gas) engines as well as the light duty diesel engine oil.
Thanks for all the replies everyone! I plan to stick with a conventional oil in this rig though as I'm not planning to keep it long term. It's gonna get thousands of miles racked up on it every year so will be getting replaced in probably 3 years or so.
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Originally Posted by aquariuscsm
Use a good 10w30. Pennzoil conventional will be perfect.
^^^^^^^^^^^^^^^^^ This ^^^^^^^^^^^^^^^^^
Use a good 10w30. Pennzoil conventional will be perfect.
^^^^^^^^^^^^^^^^^ This ^^^^^^^^^^^^^^^^^
I used to own a 2004 Monte Carlo Dale Jr. edition with the supercharged 3800 and it called for 5w30 and ran fine on it. I always ran a synthetic blend in it and did 5,000 mile changes even though it had an OLM.
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