Any personal favorite oil for GM 3800 V6 Series 2?

Messages
287
Location
Bay City Michigan
I am acquiring a 2002 pontiac bonneville with 160,000 miles as a work vehicle, and wanted some of your personal recommendations for these engines. I have been out of the "gas loop" discussion for awhile now, and have spent most of my time on here lately in the diesel oil section. I know some will say "follow owners manual" and "these engines will run on anything"... so don't flame me for asking please? The previous owner told me he ran pennzoil conventional it's first half of life, and then switched to pennzoil platinum. Uses a quart in 5,000 miles. Should I stay with the platinum and extend the interval? Do any of you think the pennzoil high mileage oil is a good option? I would like to run a UOA before I think about extending any oil to see if coolant is present in oil, as I know these engines have leaky intake gaskets. -Thank you all in advance.
 
Messages
8,306
Location
Grand Rapids, MI
I think a UOA would be a great start. I plan on doing the same with my 3800 Series II in my Firebird. I know the oil grade recommendations changed in these over the years. The one in my 1999 Firebird recommends 10W-30 above freezing, but I know a few years later they switched the recommendation to 5W-30, without changing anything internally (as far as I know). I'm using a high mileage oil in mine right now since I have a small leak that I'm hoping to slow. So far consumption has been about 1 dot on the dipstick (1/5 of a quart?) in about 1,800 miles. If it didn't have any leaks, I wouldn't be bothering with a high mileage oil. I only tend to use it in cars that leak or burn a considerable amount of oil. Sorry I couldn't be of more help, as I've only had the car for a few months now and haven't determined any preferences yet.
 
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7,432
Location
FL, USA
I have heard these engines like conventional over synthetic, as far as noise goes...so PYB would be a good choice. However, I prefer synthetic over conventional in any engine, so PP, PUP, VSP, M1 are all good choices as far as that goes.
 
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22,188
Location
Colorado Springs
I'd be more worried about the cooling system than the oil; Upper manifold EGR stovepipe leak, lower intake manifold gaskets, and heater hose elbows. Oh, and the oil pressure senders and oil filter adapter gaskets like to leak. Get all that stuff squared away and keep running whatever oil you like and it will probably get way over 200,000 miles. I've used nothing but Conventional in my Dad's 99 Olds 88 and it's nearing 230,000 miles and doesn't consume a drop of oil now that the pressure sender and filter mount gaskets have been replaced. I run 5w-30 whatever's on sale conventional in winter, 10w-30 in summer. Bright clean shiny metal under the valve covers.
 
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Messages
8,306
Location
Grand Rapids, MI
Originally Posted By: Drew99GT
I'd be more worried about the cooling system than the oil; Upper manifold EGR stovepipe leak, lower intake manifold gaskets, and heater hose elbows. Oh, and the oil pressure senders and oil filter adapter gaskets like to leak. Get all that stuff squared away and keep running whatever oil you like and it will probably get way over 200,000 miles. I've used nothing but Conventional in my Dad's 99 Olds 88 and it's nearing 230,000 miles and doesn't consume a drop of oil now that the pressure sender and filter mount gaskets have been replaced. I run 5w-30 whatever's on sale conventional in winter, 10w-30 in summer. Bright clean shiny metal under the valve covers.
Do you see any reason to change the oil filter and pressure sender if they aren't leaking? I believe the leak in my Firebird is coming from the rear of the engine (rear main or oil pan, probably). I do notice that the oil pressure gauge seems pretty inaccurate, so I'm not sure if that's a symptom of that or not. Mine is always between 60-70psi... which seems odd to me. Shouldn't it go down once it's warmed up? At hot idle, it's just a hair over 60psi. Cold idle is closer to 70. When driving around, it's at 70psi whether it's hot or cold.
 
Messages
520
Location
New York
Any 5W30 conventional or synthetic will suffice. A HM may cut into that loss of oil but it is a reasonable loss so settle on an oil and filter that fits your wallet. Though widely known for intake manifold gasket failures, the 3800 Series 2 are good engines that will last with a reasonable degree of maintenance applied. I am currently using Pennzoil Platinum for 7500 miles and will likely run a stash 5W30 Shell Formula conventional for 4500 miles. I have oil seepage out the rear valve cover with the pennzoil and will likely change out the gaskets in the Fall with the oil change and good coupons from AAP for FelPro.
 
Messages
8,051
Location
Michigan
It sounds like the previous owner was doing pretty good with PP. But at 160k, a high mileage oil wouldn't be a bad idea. Go with PP for now, and monitor oil consumption and look for leaks. Then switch to HM oil if you see any problems.
 
Messages
25,974
Location
MA, Mittelfranken.de
I have a few of these long term. PP/PU 5w30, Mobil 1 5w30 is a good oil for them. Boosted engines with their bigger injectors like Mobil 1 0w40. UOA for coolant and fuel dilution is a good idea with these. The Bosch injectors used in the Gen II can develop some bad habits when they get dirty.
 
Messages
22,188
Location
Colorado Springs
Originally Posted By: ThirdeYe
Originally Posted By: Drew99GT
I'd be more worried about the cooling system than the oil; Upper manifold EGR stovepipe leak, lower intake manifold gaskets, and heater hose elbows. Oh, and the oil pressure senders and oil filter adapter gaskets like to leak. Get all that stuff squared away and keep running whatever oil you like and it will probably get way over 200,000 miles. I've used nothing but Conventional in my Dad's 99 Olds 88 and it's nearing 230,000 miles and doesn't consume a drop of oil now that the pressure sender and filter mount gaskets have been replaced. I run 5w-30 whatever's on sale conventional in winter, 10w-30 in summer. Bright clean shiny metal under the valve covers.
Do you see any reason to change the oil filter and pressure sender if they aren't leaking? I believe the leak in my Firebird is coming from the rear of the engine (rear main or oil pan, probably). I do notice that the oil pressure gauge seems pretty inaccurate, so I'm not sure if that's a symptom of that or not. Mine is always between 60-70psi... which seems odd to me. Shouldn't it go down once it's warmed up? At hot idle, it's just a hair over 60psi. Cold idle is closer to 70. When driving around, it's at 70psi whether it's hot or cold.
That oil pressure behavior does seem wrong. The gauges in the older GMs are in fact real and not "dummy" gauges; ie, they will show the actual oil pressure. They usually start out in the 60s cold and go to around 20 at hot idle, and up into the 40s with increased rpms. Do you find any oil leaking around the oil filter area? The pressure sender is right above the oil filter. When they start to go, it will leak oil out past the electrical connectors and start dribbling down around the filter area. If you remove the passenger tire, you can get a visual of that area to determine if it's leaking; if you pull the connector on the sender and any oil is present, it's bad.
 
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Messages
8,306
Location
Grand Rapids, MI
Originally Posted By: Drew99GT
Originally Posted By: ThirdeYe
Originally Posted By: Drew99GT
I'd be more worried about the cooling system than the oil; Upper manifold EGR stovepipe leak, lower intake manifold gaskets, and heater hose elbows. Oh, and the oil pressure senders and oil filter adapter gaskets like to leak. Get all that stuff squared away and keep running whatever oil you like and it will probably get way over 200,000 miles. I've used nothing but Conventional in my Dad's 99 Olds 88 and it's nearing 230,000 miles and doesn't consume a drop of oil now that the pressure sender and filter mount gaskets have been replaced. I run 5w-30 whatever's on sale conventional in winter, 10w-30 in summer. Bright clean shiny metal under the valve covers.
Do you see any reason to change the oil filter and pressure sender if they aren't leaking? I believe the leak in my Firebird is coming from the rear of the engine (rear main or oil pan, probably). I do notice that the oil pressure gauge seems pretty inaccurate, so I'm not sure if that's a symptom of that or not. Mine is always between 60-70psi... which seems odd to me. Shouldn't it go down once it's warmed up? At hot idle, it's just a hair over 60psi. Cold idle is closer to 70. When driving around, it's at 70psi whether it's hot or cold.
That oil pressure behavior does seem wrong. The gauges in the older GMs are in fact real and not "dummy" gauges; ie, they will show the actual oil pressure. They usually start out in the 60s cold and go to around 20 at hot idle, and up into the 40s with increased rpms. Do you find any oil leaking around the oil filter area? The pressure sender is right above the oil filter. When they start to go, it will leak oil out past the electrical connectors and start dribbling down around the filter area. If you remove the passenger tire, you can get a visual of that area to determine if it's leaking; if you pull the connector on the sender and any oil is present, it's bad.
If it's right above the oil filter, I probably won't have to take off the right tire. The oil filter is located right at the front of the engine and I could probably see that area just looking under the hood (it's mounted vertically in this engine bay). I'll take a look when I get a chance. Thanks! I don't remember seeing any leaks around that area when I changed the oil back in May.
 
Messages
3,392
Location
Raleigh ,NC
I use PYB in my 2005 3800 Buick. Change it every 5000 miles.Currently has a AC Delco filter. The larger slightly one I believe PF 52. I would be happy with any GF-5 SN 5W30.
 
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Messages
460
Location
Memphis, TN.
These GM push rod engines are virtually indestructible. They originally spec'd 10w30 dino year round. Then they went to 5w30 dino when the rest of GM went that route. You could use any SL - SN rated dino in whatever flavor was on sale in either of those weights and sleep well knowing your engine is happy. Wish GM still offered them Great performance, good gas mileage, low maintenance.
 
Messages
1,981
Location
Greatest Earth on Show, UT
You should be able to get an easy 10k out of a run of PP. My 2006 GP with a supercharged 3800 Series III has an OLM and going by that, I can go out to 8.5-9k miles before hitting 0% and that is calibrated for 5W-30 with GM6094M and API starburst as the only standards to meet. If it uses 1 qt per 5k miles, I suggest running PP as your first fill, dumping it when the dipstick showing 1 qt low, and sending a sample in for a UOA with TBN, allowing you to check for coolant and TBN retention. If the TBN is good, run to 7.5-10k and run another UOA. I have done one run with PP and am on my second run with MaxLife NextGen, both in 5W-30, but can't provide much feedback on what it prefers due to my limited experience and the fact that I have had a few issues I have been battling since I bought it 18 months ago (cooling system related).
 

Ponch

Thread starter
Messages
287
Location
Bay City Michigan
Thank you all for the info.. I am excited from a cost saving standpoint to get this car (fuel mileage) compared to my "daily driver" a duramax diesel. It's time to park that rig for awhile.. While Im getting a good deal on this car, I surely expect to have to deal with the intake gaskets and such. I looked under the hood and the oil cap said 10w30... not sure if year round or just summer. I will look in owners manual. Everything looked clean under oil fill cap no sludge or anything out of ordinary. Pulled oil dipstick and didn't see any signs of milky oil (coolant in oil)...but will do a UOA this year anyways.
 
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Messages
31
Location
NY
My 01 Monte SS had 180,000 mi using Mobil 1 5w-30 the whole way...Only repairs were an injector and replacing a rusted out resonator with some straight pipe.
 
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