Hey guys, I just put in 5w 30 Castrol for this winter but I plan on using Castrol 10w 40 for next summer. I feel it offers better protection. I was debating 20w 50. What do you think?? Thanks
10w 40 in 3.8 in 03' Bonneville?
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You could get away with 10w40 during the summer, though 10w30 is recommended, but I think 20w50 would be too thick. I have the sc 3.8 and have tried various grades in my engine. The thickest I've gone is 15w40 (4 quarts) mixed with with a quart of 5w30 and I think the car felt sluggish. The car has done well with M1 0w40 in the past. These are easy engines on oil, but I'd suggest sticking to a 10w30.
You are a noobie and still confused.
Keep reading, you'll get it.
You are a noobie and still confused.
Keep reading, you'll get it.
Confused about what? We've had triple digit temperatures here this last summer. Too high for a 30 weight oil, IMO. I don't like synthetics and I stick with Castrol.
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Oh ..don't listen to those jest coast types
You'll fall into one of three main camps ..maybe 4.
1. Use the spec'd oil or you'll die a horrible, painful, death
2. Use 0w-5 ..or you'll waste more crude oil then the Queen Mary leaving port just starting up every moring
3. Heavier is better. Your engine will grenade with anything under a 40 weight. (sub note) If you want to visit Australia, keep in mind that 40 weight is "training oil" and that it's viewed like 5w-20 is here (what do you expect from "A BIG COUNTRY")
4. Custom to the application. If it can run 5w-20 without difficulty, you do. If it shows added benefit, you use a heavier weight ..without limit. That is, no set rules or theories.
You'll fall into one of three main camps ..maybe 4.
1. Use the spec'd oil or you'll die a horrible, painful, death
2. Use 0w-5 ..or you'll waste more crude oil then the Queen Mary leaving port just starting up every moring
3. Heavier is better. Your engine will grenade with anything under a 40 weight. (sub note) If you want to visit Australia, keep in mind that 40 weight is "training oil" and that it's viewed like 5w-20 is here (what do you expect from "A BIG COUNTRY")
4. Custom to the application. If it can run 5w-20 without difficulty, you do. If it shows added benefit, you use a heavier weight ..without limit. That is, no set rules or theories.
Confused about:
1) Thicker is better. It isn't. In fact a thinner oil runs cooler.
2) Hot ambient temperatures don't make your ultimate running oil temp hotter. It really doesn't directly. Sure running your AC will load your engine and a big AC condenser in front of your radiator will not help, but still there are no temps in NJ requiring a step up in viscosity.
I am not necessarily a thin or thick guy - I am a match the oil viscosity for cold start flow, engine design/mfr recommendation guy.
I wasn't pushing synthetics, either. But since you mention it, a 10W-40 dino is pretty much a poor choice. (Please read on and around)
1) Thicker is better. It isn't. In fact a thinner oil runs cooler.
2) Hot ambient temperatures don't make your ultimate running oil temp hotter. It really doesn't directly. Sure running your AC will load your engine and a big AC condenser in front of your radiator will not help, but still there are no temps in NJ requiring a step up in viscosity.
I am not necessarily a thin or thick guy - I am a match the oil viscosity for cold start flow, engine design/mfr recommendation guy.
I wasn't pushing synthetics, either. But since you mention it, a 10W-40 dino is pretty much a poor choice. (Please read on and around)
miked: If it were mine I wouldn't use a 20/50.
Many of those engines have gone 300K on 10/30 dino. The knock on 10/40 used to be 'too much vis. improver' inorder to get that large spread. These caused deposits in the ring area when they broke down. I think that modern 10/40's have improved and shouldn't be a problem but in your case are not necessary.
Many of those engines have gone 300K on 10/30 dino. The knock on 10/40 used to be 'too much vis. improver' inorder to get that large spread. These caused deposits in the ring area when they broke down. I think that modern 10/40's have improved and shouldn't be a problem but in your case are not necessary.
You could mix some 10w30 with some 10w40 for an intermediate grade.
I would use the recommended 5w30 in the winter and 10w30 in the summer. The engine is fairly new. Gas isn't cheap. As the engine gets some mileage on her, increase to 10w40 if you prefer when oil consumption goes up. I would stay away from 20w50. Just my opinion.
I have a 2001 Camaro with the 3.8 and 42,000 miles. I bought it with 4,800 miles and started out using 10w30 Amsoil as recommended in the manuel.Every thing was fine,but at 24,000 miles I switched to 0w30 Amsoil. What a diffrence. Fuel economy really improved, although it was pretty good before. My car loves it.And out here in central CA it gets plenty hot in the summer.
I have yet to see a BAD 3800 UOA, the truth is you'll be fine with just about anything, but I don't think you'll get much out of the 10w40, And I'd steer clear of the 20w50.
10w30 for summer and 5w30 for winter will work great. If you want a little thicker oil, mix in some HDEO and get more then just thickness.
I'd also recomend Chevron or Havoline
10w30 for summer and 5w30 for winter will work great. If you want a little thicker oil, mix in some HDEO and get more then just thickness.
I'd also recomend Chevron or Havoline
I used to use 20w-50 Castrol when I lived in New York in the early 1990's (uhm, 1990-1994). Never had a problem, even on days I when had to use a shovel to dig my car out of the snow. Later on, in 1995-1998, I switched to Castrol HD-30. This stuff is even thicker than 20w-50. Again, never had a problem starting on the coldest days. Did not have a single oil-related problem the whole time.
Flimflam: At operatung temperatures, SAE 30 HD oils are *not* thicker than 20W50.
You could be right at 40F degrees, I suppose.
And yeah, if you live in Texas, you should be able to run straight 30 with no problem.
You could be right at 40F degrees, I suppose.
And yeah, if you live in Texas, you should be able to run straight 30 with no problem.
The owners manual of my '02 Bonneville specifically stated "do not use other weights such as 10w40 or 20w50". I too have the 3.8L engine. Why go against the GM engineers advice?
Stick with the 10w30, any brand carrying the STARBURST and the SL/SM/GF3or4 rating. Havoline is a great buy in most places.
Stick with the 10w30, any brand carrying the STARBURST and the SL/SM/GF3or4 rating. Havoline is a great buy in most places.
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Yes, but why did they state that? I doubt that it was necessarily due to the weight itself. It may have been for sensible economy reasons ..or the VII in those weights that would have other liabilities.
Try and integrate what I'm stuggling to communicate.
Grounding the football for yardage is a penalty
Grounding the football for time, is not.
you don't need heavy oils on the 3.8, I got a great 3.8 UOA with 99 cent Mobil Drive Clean 10w30 in the summer down here in Austin, Texas. I GUARANTEE you it's hotter here than in New Jersey.
Unless you are experiencing significant oil usage with 10w30 (not likely in a vehicle as new as '03) there is no reason to use 10w40 and fuel economy may decrease with the thicker oil.
Miked, these folks are good people
BITOG'ers really have your best interest in mind. They really do
Please just listen, read, change your paradime and think out of the box. The lubes these folks suggest are top notch. Synthetics...top notch and affordable. Do a search of different viscositys, oils, analysis, and the like...you will be pleasently suprized
Really...give us a try and think out of the box. I think either Mobil one 5-40 fully synthetic T&C or Amsoil 5-40 Europeon oil will do the trick year round...take the plunge, your sure to go 1 year or 15,000 miles on an oil change...Really.. Otherwise, continue to use your formula and do 5000 mile oil and filter changes...You don't need the 20-50...CUMANATADA
I have come around to the fact that you use thin unless you have leaking or burning issues you cant fix or dont want to fix. a friend or relative with such a car would get the thicker oil from me to protect from running into danger. for that healthy 3.8 I would go trop artic syn blend 5-30 or 10-30.
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